Copeptin Levels Before and After Transsphenoidal Surgery for Cushing Disease: A Potential Early Marker of Remission

Posted on May 16, 2022 by MaryO

Abstract

Context

Arginine-vasopressin and CRH act synergistically to stimulate secretion of ACTH. There is evidence that glucocorticoids act via negative feedback to suppress arginine-vasopressin secretion.

Objective

Our hypothesis was that a postoperative increase in plasma copeptin may serve as a marker of remission of Cushing disease (CD).

Design

Plasma copeptin was obtained in patients with CD before and daily on postoperative days 1 through 8 after transsphenoidal surgery. Peak postoperative copeptin levels and Δcopeptin values were compared among those in remission vs no remission.

Results

Forty-four patients (64% female, aged 7-55 years) were included, and 19 developed neither diabetes insipidus (DI) or syndrome of inappropriate anti-diuresis (SIADH). Thirty-three had follow-up at least 3 months postoperatively. There was no difference in peak postoperative copeptin in remission (6.1 pmol/L [4.3-12.1]) vs no remission (7.3 pmol/L [5.4-8.4], P = 0.88). Excluding those who developed DI or SIADH, there was no difference in peak postoperative copeptin in remission (10.2 pmol/L [6.9-21.0]) vs no remission (5.4 pmol/L [4.6-7.3], P = 0.20). However, a higher peak postoperative copeptin level was found in those in remission (14.6 pmol/L [±10.9] vs 5.8 (±1.4), P = 0.03]) with parametric testing. There was no difference in the Δcopeptin by remission status.

Conclusions

A difference in peak postoperative plasma copeptin as an early marker to predict remission of CD was not consistently present, although the data point to the need for a larger sample size to further evaluate this. However, the utility of this test may be limited to those who develop neither DI nor SIADH postoperatively.

Arginine vasopressin (AVP) and CRH act synergistically as the primary stimuli for secretion of ACTH, leading to release of cortisol [1, 2]. The role of AVP in the hypothalamic-pituitary-adrenal (HPA) axis is via release from the parvocellular neurons of the paraventricular nuclei (and possibly also from the magnocellular neurons of the paraventricular and supraoptic nuclei), the secretion of which is stimulated by stress [3-6]. AVP release results in both independent stimulation of ACTH release and potentiation of the effects of CRH [3, 7-9]. Additionally, there is evidence that glucocorticoids act by way of negative feedback to suppress AVP secretion [10, 11-20]. Further, parvocellular neurons of the hypothalamic paraventricular nuclei have been shown to increase AVP production and neurosecretory granule size after adrenalectomy, and inappropriately elevated plasma AVP has been reported in the setting of adrenal insufficiency with normalization of plasma AVP after glucocorticoid administration [21-24]. This relationship of AVP and its effect on the HPA axis has been used in the diagnostic evaluation of Cushing syndrome (CS) [14] and evaluation of remission after transsphenoidal surgery (TSS) in Cushing disease (CD) by administration of desmopressin [25].

Copeptin makes up the C-terminal portion of the AVP precursor pre-pro-AVP. Copeptin is released from the posterior pituitary in stoichiometric amounts with AVP, and because of its longer half-life in circulation, it is a stable surrogate marker of AVP secretion [26-28]. Plasma copeptin has been studied in various conditions of the anterior pituitary. In a study by Lewandowski et al, plasma copeptin was measured after administration of CRH in assessment of HPA-axis function in patients with a variety of pituitary diseases. An increase in plasma copeptin was observed only in healthy subjects but not in those with pituitary disease who had an appropriately stimulated serum cortisol, and the authors concluded that copeptin may be a sensitive marker to reveal subtle alterations in the regulation of pituitary function [7]. Although in this study and others, plasma copeptin was assessed after pituitary surgery, it has not, to the best of our knowledge, been studied as a marker of remission of CD before and after pituitary surgery [7, 29].

In this study, plasma copeptin levels were assessed as a surrogate of AVP secretion before and after TSS for treatment of CD. Because there is evidence that glucocorticoids exert negative feedback on AVP, we hypothesized that there would be a greater postoperative increase in plasma copeptin in those with CD in remission after TSS resulting from resolution of hypercortisolemia and resultant hypocortisolemia compared with those not in remission with persistent hypercortisolemia and continued negative feedback. In other words, we hypothesized that an increase in copeptin could be an early marker of remission of CD after TSS. We aimed to complete this assessment by comparison of the peak postoperative copeptin and change in copeptin from preoperative to peak postoperative copeptin for those in remission vs not in remission postoperatively.

Subjects and Methods

Subjects

Adult and pediatric patients with CD who presented at the Eunice Kennedy Shriver National Institute of Child Health and Human Development under protocol 97-CH-0076 and underwent TSS between March 2016 and July 2019 were included in the study. Exclusion criteria included a prior TSS within 6 weeks of the preoperative plasma copeptin sample or a preoperative diagnosis of diabetes insipidus, renal disease, or cardiac failure. Written informed consent was provided by patients aged 18 years and older and by legal guardians for patients aged < 18 years to participate in this study. Written informed assent was provided by patients aged 7 years to < 18 years. The 97-CH-0076 study (Investigation of Pituitary Tumors and Related Hypothalamic Disorders) has been approved by the Eunice Kennedy Shriver National Institute of Child Health and Human Development institutional review board.

Clinical and Biochemical Data

Clinical data were extracted from electronic medical records. Age, sex, body weight, body mass index (BMI), pubertal stage (in pediatric patients only), and history of prior TSS were obtained preoperatively during the admission for TSS. Clinical data obtained postoperatively included TSS date, histology, development of central diabetes insipidus (DI) or (SIADH), time from TSS to most recent follow-up, and clinical remission status at postoperative follow-up.

Preoperatively, serum sodium, 24-hour urinary free cortisol (UFC), UFC times the upper limit of normal (UFC × ULN), midnight (MN) serum cortisol, MN plasma ACTH, and 8 AM plasma ACTH were collected. Postoperatively, serum sodium, serum and urine osmolality, urine specific gravity, serum cortisol, and plasma ACTH were collected. For serum cortisol values < 1 mcg/dL, a value of 0.5 mcg/dL was assigned for the analyses; for plasma ACTH levels < 5 pg/mL, a value of 2.5 pg/mL was assigned.

Additionally, plasma copeptin levels were obtained preoperatively and on postoperative days (PODs) 1 through 8 after TSS at 8:00 AM. Peak postoperative copeptin was the highest plasma copeptin on PODs 1 through 8. The delta copeptin (Δcopeptin) was determined by subtracting the preoperative copeptin from the peak postoperative copeptin; hence, a positive change indicated a postoperative increase in plasma copeptin. Plasma copeptin was measured using an automated immunofluorescent sandwich assay on the BRAHMS Kryptor Compact PLUS Copeptin-proAVP. The limit of detection for the assay was 1.58 pmol/L, 5.7% intra-assay coefficient of variation, and 11.2% inter-assay coefficient of variation, with a lower limit of analytical measurement of 2.8 pmol/L. For those with multiple preoperative plasma copeptin values within days before surgery, an average of preoperative copeptin levels was used for analyses.

Diagnosis of CD was based on guidelines published by the Endocrine Society and as previously described for the adult and pediatric populations [30, 31]; diagnosis was further confirmed by either histologic identification of an ACTH-secreting pituitary adenoma in the resected tumor specimen, decrease in cortisol and ACTH levels postoperatively, and/or clinical remission after TSS at follow-up evaluation. All patients were treated with TSS at the National Institutes of Health Clinical Center by the same neurosurgeon. Remission after surgical therapy was based on serum cortisol of < 5 μg/dL during the immediate postoperative period, improvement of clinical signs and symptoms of cortisol excess at postoperative follow up, nonelevated 24-hour UFC at postoperative follow-up, nonelevated midnight serum cortisol at postoperative follow up when available, and continued requirement for glucocorticoid replacement at 3 to 6 months’ postoperative follow-up.

Diagnosis of SIADH was based on development of hyponatremia (serum sodium < 135 mmol/L) and oliguria (urine output < 0.5 mL/kg/h). Diagnosis of DI was determined by development of hypernatremia (serum sodium > 145 mmol/L), dilute polyuria (urine output > 4 mL/kg/h), elevated serum osmolality, and low urine osmolality.

Statistical Analyses

Results are presented as median (interquartile range [IQR], calculated as 25th percentile-75th percentile) or mean ± SD, as appropriate, and frequency (percentage). Where appropriate, we compared results using parametric or nonparametric testing; however, the median (IQR) and the mean ± SD were both reported to allow for comparisons with the appropriate testing noted. Subgroup analyses were completed comparing those who developed water balance disorders included patients who developed DI only (but not SIADH), those who developed SIADH only (but not DI), and those with no water balance disorder; hence, for these subgroup analyses, those who developed both DI and SIADH postoperatively (n = 4) were excluded. Preoperative copeptin, peak postoperative copeptin, and Δcopeptin were compared between those with and without remission at follow-up, using either t test or Wilcoxon rank-sum test, depending on the distribution of data. These were done in all patients combined, as well as within each subgroup. The same tests were used for comparing other continuous variables (eg, age, BMI SD score [SDS], cortisol excess measures) between those with and without remission. Categorical data (eg, sex, Tanner stage) were analyzed using the Fisher exact test. Comparisons of copeptin levels among the subgroups (DI, SIADH, neither) were carried out using mixed models and the Kruskal-Wallis test, as appropriate. Post hoc pairwise comparisons were adjusted for multiplicity using the Bonferroni correction, and as applicable, only corrected P values are reported. Mixed models for repeated measures also analyzed copeptin, serum sodium, and cortisol data for PODs 1 through 8. In addition, maximum likelihood estimation (GENMOD) procedures analyzed the effects of copeptin and serum sodium on the remission at follow-up. Correlation analyses were done with Spearman ρ. All analyses were tested for the potential confounding effects of age, sex, BMI SDS, and pubertal status, and were adjusted accordingly. For plasma copeptin reported as < 2.8 pmol/L, a value of 1.4 pmol/L (midpoint of 0 and 2.8 pmol/L) was used; sensitivity analyses repeated all relevant comparisons using the threshold limit of 2.8 pmol/L instead of 1.4 pmol/L. Odds ratios (OR) and 95% CIs, other magnitudes of the effect, data variability, and 2-sided P values provided the statistical evidence for the conclusions. Statistical analyses were performed in SAS version 9.4 software (SAS Institute, Inc, Cary, NC).

Results

Patient Characteristics

Forty-four adult and pediatric patients, aged 7 to 55 years (77.2% were < 18 years old), with CD were included in the study. The cohort included 28 female patients (64%), and the median BMI SDS was 2.2 (1.1-2.5). Thirty-four percent (15/44) had prior pituitary surgery (none within the prior 6 weeks). Seventy-five percent (33/44) had postoperative follow-up evaluations available, with median follow-up of 13.5 months (11.3-16.0). Of those 33 patients, 85% were determined to be in remission at follow-up. Comparing those in remission vs no remission, there was no difference in age, sex, BMI SDS, pubertal status (in pediatric ages only), preoperative measures of cortisol excess (UFC × ULN, PM serum cortisol, MN plasma ACTH, AM plasma ACTH), duration of follow-up, or development of DI or SIADH. There was a lower postoperative serum cortisol nadir in those in remission at follow-up compared with those not in remission at follow-up, as expected, because a postoperative serum cortisol < 5 μg/dL was included in defining remission status. Postoperatively, 8/44 (18%) developed DI, 13/44 (30%) developed SIADH, 4/44 (9%) developed both DI and SIADH, and 19/44 (43%) developed no water balance disorder (Table 1). There were no differences by remission status when assessing these subgroups (ie, DI, SIADH, and no water balance disorder) separately.

 
Table 1.

Demographic and clinical characteristics of subjects

All subjects, n = 44 All subjects by remission status, n = 33 All subjects by remission status, excluding those with DI or SIADH, n = 13
Remission, n = 28 No remission, n = 5 P Remission,
n = 10		 No remission, n = 3 P
Age, median (range), y 14.5 (7-55) 17.4 ± 10.7
14.5 (12.5-17.5)		 15.6 ± 13.2
11.0 (9.0-12.0)		 0.11 13.7 ± 3.1
14.0 (13.0-15.0)		 19.7 ± 16.8
11.0 (9.0-39.0)		 0.60a
Sex
Female		 28 (64%) 22 (78.6%) 3 (60.0%) 0.57 9 (90.0%) 2 (66.7%) 0.42
BMI SDS 2.2 (1.1-2.5) 1.7 ± 1.0
2.0 (0.9-2.5)		 2.2 ± 0.4
2.2 (2.1-2.3)		 0.70 1.7 ± 1.1
2.0 (0.7-2.5)		 2.0 ± 0.4
2.1 (1.5-2.3)		 0.65a
Pubertal status
Female (n = 19) (n = 15) (n = 2) 0.51 (n = 8) (n = 1) 0.44
  Tanner 1-2 6 4 (26.7%) 1 (50.0%) 3 (37.5%) 1 (25.0%)
  Tanner 3-5 13 11 (73.3%) 1 (50.0%) 5 (62.5%) 0
Male (n = 14) (n = 5) (n = 2) (n = 1) (n = 1) —
Testicular volume < 12, mL 10 4 (80.0%) 2 (10.00%) 1 (100.0%) 1 (100.0%)
Testicular volume ≥ 12, mL 4 1 (20.0%) 0 1.0 0 0
Preoperative UFC ULN 3.3 (1.2-6.1) 4.9 ± 6.1
2.6 (1.0-7.6)		 3.2 ± 1.3
3.7 (3.0-3.9)		 0.70 7.2 ± 8.4
3.9 (1.8-9.1)		 3.8 ± 0.7
3.9 (3.0-4.4)		 0.93
Preoperative PM cortisol 11.9 (9.2-14.8) 13.3 ± 4.7
12.2 (9.2-16.8)		 10.8 ± 2.1
11.5 (9.0-11.6)		 0.30 13.3 ± 6.0
11.2 (8.4-16.5)		 11.1 ± 2.6
11.6 (8.3-13.6)		 0.57a
Preoperative MN ACTH 43.4 (29.3-51.6) 44.2 ± 25.5
46.1 (27.6-50.5)		 40.9 ± 15.3
11.5 (9.0-11.6)		 0.74 36.6 ± 16.6
37.4 (29.1-48.8)		 34.0 ± 9.4
39.3 (23.1-39.5)		 0.67
Preoperative AM ACTH 44.6 (31.4-60.5) 46.9 ± 28.9
44.0 (29.8-56.2)		 48.6 ± 28.8
58.7 (21.7-60.5)		 0.84 35.2 ± 16.2
40.3 (28.0-44.0)		 45.4 ± 24.6
58.7 (17.0-60.5)		 0.41a
Postoperative cortisol nadir 0.5 (0.5-0.5) 0.7 ± 0.7
0.5 (0.5-0.5)		 7.8 ± 6.6
5.2 (2.2-12.3)		 <0.001 0.6 ± 0.3
0.5 (0.5-0.5)		 8.1 ± 7.9
5.2 (2.1-17.0)		 0.003
Duration of follow-up 13.5 (11.3-16.0) 15.3 ± 7.9
14.0 (12.0-16.5)		 14.0 ± 13.0
11.0 (6.0-14.0)		 0.30 18.6 ± 11.2
15.5 (12.0-27.0)		 16.7 ± 17.2
11.0 (3.0-36.0)		 0.82a
DI only 8 (18%) 7/8 (87.5%) 1/8 (12.5%) 0.91 — — —
SIADH only 13 (30%) 8/9 (88.9%) 1/9 (11.1%)
Neither DI/SIADH 19 (43%) 10/13 (76.9%) 3/13 (23.1%)
Both DI and SIADH 4 (9%) 3/3 (100%) 0/3

Demographic and clinical characteristics of all subjects (n = 44) with Cushing disease. Data are also presented by remission status for all subjects with postoperative follow-up (n = 33) and by remission status after excluding those who developed DI or SIADH postoperatively with postoperative follow-up (n = 13). Both median (IQR) and mean ± SD reported to allow for comparisons, with P value provided using appropriate testing depending on distribution of data sets. Data are mean ± SD, median (25th-75th IQR), or frequency (percentage) are reported, except for age, which is presented as median (range).

Abbreviations: AM, 7:30-8 PM; BMI, body mass index; DI, diabetes insipidus; IQR, interquartile range; MN, midnight; N/A, not applicable; SDS, SD score; SIADH, syndrome of inappropriate antidiuresis; UFC, urinary free cortisol; ULN, upper limit of normal. p-values below the threshold of 0.05 are in bold.

aP value indicates comparison using parametric testing, as appropriate for normally distributed data.

Preoperative copeptin levels were higher in males (7.0 pmol/L [5.1-9.6]) than in females (4.0 pmol/L [1.4-5.8], P = 0.004) (Fig. 1). Age was inversely correlated with preoperative copeptin (rs = -0.35, P = 0.030) and BMI SDS was positively correlated with preoperative copeptin (rs = 0.54, P < 0.001) (Fig. 2).

 

Figure 1.

Preoperative plasma copeptin and sex. Preoperative plasma copeptin in all patients, comparing by sex. A higher preoperative plasma copeptin was found in males (7.0 pmol/L [5.1-9.6]) than in females (4.0 pmol/L [1.4-5.8], P = 0.004). Horizontal lines = median. Whiskers = 25th and 75th interquartile ranges.

Preoperative plasma copeptin and sex. Preoperative plasma copeptin in all patients, comparing by sex. A higher preoperative plasma copeptin was found in males (7.0 pmol/L [5.1-9.6]) than in females (4.0 pmol/L [1.4-5.8], P = 0.004). Horizontal lines = median. Whiskers = 25th and 75th interquartile ranges.

 

Figure 2.

Preoperative plasma copeptin and BMI SDS. Association of preoperative plasma copeptin and BMI SDS in all patients. A BMI SDS was positively associated with a preoperative plasma copeptin (rs = 0.54, P < 0.001). Shaded area = 95% confidence interval.

Preoperative plasma copeptin and BMI SDS. Association of preoperative plasma copeptin and BMI SDS in all patients. A BMI SDS was positively associated with a preoperative plasma copeptin (rs = 0.54, P < 0.001). Shaded area = 95% confidence interval.

Copeptin Before and After Transsphenoidal Surgery for CD

Among the 33 patients with postoperative follow-up, there was no difference in peak postoperative copeptin for patients in remission vs those not in remission (6.1 pmol/L [4.3-12.1] vs 7.3 pmol/L [5.4-8.4], P = 0.88). There was also no difference in the Δcopeptin for those in remission vs not in remission (2.3 pmol/L [-0.5 to 8.2] vs 0.1 pmol/L [-0.1 to 2.2], P = 0.46) (Fig. 3). Including all subjects, the mean preoperative copeptin was 5.6 pmol/L (±3.4). For patients with follow-up, there was no difference in preoperative copeptin for those in remission (4.8 pmol/L [±2.9]) vs no remission (6.0 pmol/L [±2.0], P = 0.47). POD 1 plasma copeptin ranged from < 2.8 to 11.3 pmol/L.

 

Figure 3.

(A) Peak postoperative plasma copeptin in all patients, comparing those in remission with no remission (6.1 pmol/L [4.3-12.1] vs 7.3 pmol/L [5.4-8.4], P = 0.88). (B) ΔCopeptin (preoperative plasma copeptin subtracted from postoperative peak plasma copeptin) in all patients, comparing those in remission with no remission (2.3 pmol/L [-0.5 to 8.2] vs 0.1 pmol/L [-0.1 to 2.2], P = 0.46). Horizontal lines = median. Whiskers = 25th and 75th interquartile ranges.

(A) Peak postoperative plasma copeptin in all patients, comparing those in remission with no remission (6.1 pmol/L [4.3-12.1] vs 7.3 pmol/L [5.4-8.4], P = 0.88). (B) ΔCopeptin (preoperative plasma copeptin subtracted from postoperative peak plasma copeptin) in all patients, comparing those in remission with no remission (2.3 pmol/L [-0.5 to 8.2] vs 0.1 pmol/L [-0.1 to 2.2], P = 0.46). Horizontal lines = median. Whiskers = 25th and 75th interquartile ranges.

When those who developed DI or SIADH were excluded, there was no difference in peak postoperative copeptin in those in remission vs no remission (10.2 pmol/L [6.9-21.0] vs 5.4 pmol/L [4.6-7.3], P = 0.20). However, because the distribution of the peak postoperative copeptins was borderline normally distributed, parametric testing was also completed for this analysis, which showed a higher peak postoperative copeptin in remission (14.6 pmol/L [±10.9]) vs no remission (5.8 [±1.4], P = 0.03). There was no difference in the Δcopeptin for those in remission vs not in remission (5.1 pmol/L [0.3-19.5] vs 1.1 pmol/L [-0.1 to 2.2], P = 0.39) (Fig. 4). Preoperative copeptin was not different for those in remission (4.7 pmol/L [±2.4]) vs no remission (4.9 pmol/L [±20.3], P = 0.91). There was no association between serum cortisol and plasma copeptin over time postoperatively (Fig. 5).

 

Figure 4.

(A) Peak postoperative plasma copeptin excluding those who developed DI or SIADH, comparing those in remission with no remission (10.2 pmol/L [6.9-21.0] vs 5.4 pmol/L [4.6-7.3], P = 0.20). (B) ΔCopeptin (preoperative plasma copeptin subtracted from postoperative peak plasma copeptin) excluding those who developed DI or SIADH, comparing those in remission with no remission (5.1 pmol/L [0.3-19.5] vs 1.1 pmol/L [-0.1 to 2.2], P = 0.39). Horizontal lines = median. Whiskers = 25th and 75th interquartile ranges.

(A) Peak postoperative plasma copeptin excluding those who developed DI or SIADH, comparing those in remission with no remission (10.2 pmol/L [6.9-21.0] vs 5.4 pmol/L [4.6-7.3], P = 0.20). (B) ΔCopeptin (preoperative plasma copeptin subtracted from postoperative peak plasma copeptin) excluding those who developed DI or SIADH, comparing those in remission with no remission (5.1 pmol/L [0.3-19.5] vs 1.1 pmol/L [-0.1 to 2.2], P = 0.39). Horizontal lines = median. Whiskers = 25th and 75th interquartile ranges.

 

Figure 5.

Plasma copeptin and serum cortisol vs postoperative day for patients who did not develop DI or SIADH. Plasma copeptin (indicated by closed circle) and serum cortisol (indicated by “x”). Results shown as (median, 95% CI).

Plasma copeptin and serum cortisol vs postoperative day for patients who did not develop DI or SIADH. Plasma copeptin (indicated by closed circle) and serum cortisol (indicated by “x”). Results shown as (median, 95% CI).

All analyses here were repeated adjusting for serum sodium, and there were no differences by remission status for preoperative, peak postoperative, or Δcopeptin for all subjects or after excluding those who developed a water balance disorder (data not shown).

Copeptin and Water Balance Disorders

As expected, peak postoperative copeptin appeared to be different among patients who developed DI, SIADH, and those without any fluid balance disorder (P = 0.029), whereas patients with DI had lower median peak postoperative copeptin (4.4 pmol/L [2.4-6.9]) than those who developed no fluid abnormality (10.0 pmol/L [5.4-16.5], P = 0.04), the statistical difference was not present after correction for multiple comparisons (P = 0.13). Peak postoperative copeptin of patients with SIADH was 9.4 pmol/L (6.5-10.4) and did not differ from patients with DI (P = 0.32) or those with no fluid abnormality (P = 1.0). There was a difference in Δcopeptin levels among these subgroups (overall P = 0.043), which appeared to be driven by the lower Δcopeptin in those who developed DI (-1.2 pmol/L [-2.6 to 0.1]) vs in those with neither DI or SIADH (3.1 pmol/L [0-9.6], P = 0.05). However, this pairwise comparison did not reach statistical significance, even before correction for multiple comparisons (P = 0.16) (Fig. 6). Preoperative copeptin levels were also not different among the subgroups (P = 0.54).

 

Figure 6.

(A) Peak postoperative plasma copeptin, comparing those who developed DI, SIADH, or neither (P = 0.029 for comparison of all 3 groups). (B) ∆ Copeptin (preoperative plasma copeptin subtracted from postoperative peak plasma copeptin), comparing those who developed DI, SIADH, or neither (P = 0.043 for comparison of all 3 groups). Horizontal lines = median. Whiskers = 25th and 75th interquartile ranges. Top brackets = pairwise comparisons. P values presented are after Bonferroni correction for multiple comparisons.

(A) Peak postoperative plasma copeptin, comparing those who developed DI, SIADH, or neither (P = 0.029 for comparison of all 3 groups). (B) ∆ Copeptin (preoperative plasma copeptin subtracted from postoperative peak plasma copeptin), comparing those who developed DI, SIADH, or neither (P = 0.043 for comparison of all 3 groups). Horizontal lines = median. Whiskers = 25th and 75th interquartile ranges. Top brackets = pairwise comparisons. P values presented are after Bonferroni correction for multiple comparisons.

Association of Sodium and Copeptin

Longitudinal data, adjusting for subgroups (ie, DI, SIADH, neither), were analyzed. As expected, there was a group difference (P = 0.003) in serum sodium over time (all DI was missing preoperative serum sodium), with the difference being driven by DI vs SIADH (P = 0.007), and SIADH vs neither (P = 0.012). There was no group difference in plasma copeptin over POD by water balance status (P = 0.16) over time (Fig. 7). There was also no effect by remission status at 3 to 6 months for either serum sodium or plasma copeptin.

 

Figure 7.

(A) Serum sodium and (B) plasma copeptin by POD and water balance status longitudinal data, adjusting for subgroups (ie, DI, SIADH, neither). Data points at point 0 on the x-axis indicate preoperative values. As expected, there was a group difference (P = 0.003) in serum sodium over time (all with DI were missing preoperative serum sodium), with the difference being driven by DI vs SIADH (P = 0.007), and SIADH vs neither (P = 0.012). There was no group difference in plasma copeptin over POD by water balance status (P = 0.16) over time.

(A) Serum sodium and (B) plasma copeptin by POD and water balance status longitudinal data, adjusting for subgroups (ie, DI, SIADH, neither). Data points at point 0 on the x-axis indicate preoperative values. As expected, there was a group difference (P = 0.003) in serum sodium over time (all with DI were missing preoperative serum sodium), with the difference being driven by DI vs SIADH (P = 0.007), and SIADH vs neither (P = 0.012). There was no group difference in plasma copeptin over POD by water balance status (P = 0.16) over time.

Higher serum sodium levels from PODs 1 through 8 itself decreased the odds of remission (OR, 0.56; 95% CI, 0.42-0.73; P < 0.001) in all CD patients. Copeptin levels from these repeated measures adjusting for serum sodium did not correlate with remission status at 3 to 6 months’ follow-up (P = 0.38). There were no differences in preoperative, peak postoperative, or delta sodium levels by remission vs no remission in all patients and in those with no water balance disorders.

Discussion

AVP and CRH act synergistically to stimulate the secretion of ACTH and ultimately cortisol [1, 2], and there is evidence that glucocorticoids act by way of negative feedback to suppress AVP secretion [10, 11-20]. Therefore, we hypothesized that a greater postoperative increase in plasma copeptin in those with CD in remission after TSS because of resolution of hypercortisolemia and resultant hypocortisolemia, compared with those not in remission with persistent hypercortisolemia and continued negative feedback, would be observed. Although a clear difference in peak postoperative and Δcopeptin was not observed in this study, a higher peak postoperative copeptin was found in those in remission after excluding those who developed DI/SIADH when analyzing this comparison with parametric testing, and it is possible that we did not have the power to detect a difference by nonparametric testing, given our small sample size. Therefore, postoperative plasma copeptin may be a useful early marker to predict remission of CD after TSS. The utility of this test may be limited to those who do not develop water balance disorders postoperatively. If a true increase in copeptin occurs for those in remission after treatment of CD, it is possible that this could be due to the removal of negative feedback from cortisol excess on pre-pro-AVP secretion, as hypothesized in this study. However, it is also possible that other factors may contribute to an increase in copeptin postoperatively, including from the stress response of surgery and postoperative hypocortisolism and resultant stimulation of pre-pro-AVP secretion from these physical stressors and/or from unrecognized SIADH.

It was anticipated that more severe hypercortisolism to be negatively correlated with preoperative plasma copeptin because of greater negative feedback on AVP. However, no association was found between preoperative plasma copeptin and markers of severity of hypercortisolism (MN cortisol, AM ACTH, UFC × ULN) in this study. Similarly, we would expect that the preoperative plasma copeptin would be lower compared with healthy individuals. However, comparisons of healthy individuals may be difficult because the fluid and osmolality status at the time of the sample could influence the plasma copeptin, and depending on those factors, copeptin could be appropriately low. A healthy control group with whom to compare the preoperative values was not available for this study, and the thirsted state was not standardized for the preoperative copeptin measurements. Future studies could be considered to determine if preoperative plasma copeptin is lower in patients with CD, or other forms of CS, compared with healthy subjects, with all subjects thirsted for an equivalent period. Further, if preoperative plasma copeptin is found to be lower in thirsted subjects with CS than a thirsted healthy control group, the plasma copeptin could potentially be a diagnostic test to lend support for or against the diagnosis of endogenous CS.

In the comparisons of those who developed DI, SIADH, or neither, no difference was found in the Δcopeptin. Peak copeptin was lower in DI compared with those without DI or SIADH (but not different from SIADH). Again, it is possible that there is a lower peak postoperative copeptin and change in copeptin in those with DI, but we may not have had the power to detect this in all of our analyses. These comparisons of copeptin among those with or without water balance disorders postoperatively are somewhat consistent with a prior study showing postoperative copeptin as a good predictor of development of DI, in which a plasma copeptin < 2.5 pmol/L measured on POD 0 accurately identified those who developed DI, and plasma copeptin > 30 pmol/L ruled out the development of DI postoperatively [29]. In the current study, 3 of 6 subjects with DI had a POD 1 plasma copeptin < 2.5 pmol/L, and none had a POD 1 plasma copeptin > 30 pmol/L. However, the study by Winzeler et al found that copeptin measured on POD 0 (within 12 hours after surgery) had the greatest predictive value, and POD 0 plasma copeptin was not available in our study. Further, we used the preoperative, peak, and delta plasma copeptin for analyses, so the early low copeptin levels may not have been captured in our data and analyses.

Additionally, this study revealed that increasing levels of serum sodium have lower odds of remission. Those who have an ACTH-producing adenoma that is not identified by magnetic resonance imaging and visual inspection intraoperatively have lower rates of remission and are more likely to have greater manipulation of the pituitary gland intraoperatively [32-36], and the latter may result in greater damage to the pituitary stalk or posterior pituitary, increasing the risk for development of DI and resultant hypernatremia.

A higher preoperative copeptin was associated with male sex and increasing BMI SDS. Increasing preoperative copeptin was also found in pubertal boys compared with pubertal girls, with no difference in copeptin between prepubertal boys and girls. It is particularly interesting to note that these associations were only in the preoperative plasma copeptin levels, but not the postoperative peak copeptin or Δcopeptin. Because the association of higher plasma in adult males and pubertal males in comparison to adult females and pubertal females, respectively, have been reported by others [26, 37-40], it raises the question of a change in the association of sex and BMI with plasma copeptin in the postoperative state. An effect of BMI or sex was not found by remission status, so it does not seem that the postoperative hypocortisolemic state for those in remission could explain this loss of association. However, this study may not have been powered to detect this.

Strengths of this study include the prospective nature of the study. Further, this is the first study assessing the utility of copeptin to predict remission after treatment of CD. Limitations of this study include the small sample size because of the rarity of the condition, difficulty in clinically diagnosing DI and SIADH, potential effect of post-TSS fluid balance disorders (particularly for those who may have developed transient partial DI or transient SIADH), lack of long-term follow-up, lack of any postoperative follow-up in 11 of the 44 total subjects, as well the observational nature of the study. Further, it is possible that pubertal status, sex, and BMI may have affected copeptin levels, which may have not been consistently detected because of lack of power. Lack of data on the timing of hydrocortisone replacement is an additional limitation of this study because postoperative glucocorticoid replacement could affect AVP secretion via negative feedback. Additional studies are needed to assess to further assess the role of vasopressin and measurement of copeptin in patients before and after treatment of CD.

A clear difference in peak postoperative plasma copeptin as an early marker to predict remission of CD after TSS was not found. Further studies with larger sample sizes are needed to further evaluate postoperative plasma copeptin as an early marker to predict remission of CD, though the utility of this test may be limited to those who do not develop water balance disorders postoperatively. Future studies comparing copeptin levels before and after treatment of adrenal CS would be of particular interest because this would minimize the risk of postoperative DI or SIADH which also influence copeptin levels. Additionally, comparison of thirsted preoperative plasma copeptin in those with endogenous CS and thirsted plasma copeptin in healthy controls could potentially provide evidence of whether or not preoperative plasma copeptin is lower in patients with CD, or other forms of CS, compared with healthy subjects. Further, if this is found to be true, it could potentially be a diagnostic test to lend support for or against endogenous CS.

Abbreviations

 

  • AVP

    arginine vasopressin

  • BMI

    body mass index

  • CD

    Cushing disease

  • CS

    Cushing syndrome

  • DI

    diabetes insipidus

  • HPA

    hypothalamic-pituitary-adrenal

  • IQR

    interquartile range

  • MN

    midnight

  • OR

    odds ratio

  • POD

    postoperative day

  • SDS

    SD score

  • SIADH

    syndrome of inappropriate antidiuresis

  • TSS

    transsphenoidal surgery

  • UFC

    urinary free cortisol

  • ULN

    upper limit of normal

Acknowledgments

The authors thank the patients and their families for participating in this study.

Funding

This work was supported by the Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD), National Institutes of Health.

Disclosures

C.A.S. holds patents on technologies involving PRKAR1A, PDE11A, GPR101, and related genes, and his laboratory has received research funding support by Pfizer Inc. for investigations unrelated to this project. C.A.S. is associated with the following pharmaceutical companies: ELPEN, Inc., H. Lunbeck A/S, and Sync. Inc.

Clinical Trial Information

ClinicalTrials.gov registration no. NCT00001595 (registered November 4, 1999).

Data Availability

Some or all datasets generated during and/or analyzed during the current study are not publicly available but are available from the corresponding author on reasonable request.

Published by Oxford University Press on behalf of the Endocrine Society 2022.
This work is written by (a) US Government employee(s) and is in the public domain in the US.

Filed under: Cushing's, pituitary, Treatments | Tagged: , , , | Leave a comment »

Endoscopic vs. Microscopic Transsphenoidal Surgery for the Treatment of Pituitary Adenoma

Posted on February 28, 2022 by MaryO

This article was originally published here

Front Surg. 2022 Feb 2;8:806855. doi: 10.3389/fsurg.2021.806855. eCollection 2021.

ABSTRACT

PURPOSE: Currently, endoscopic transsphenoidal surgery (ETS) and microscopic transsphenoidal surgery (MTS) are commonly applied treatments for patients with pituitary adenomas. This meta-analysis was conducted to evaluate the efficacy and safety of ETS and MTS for these patients.

METHODS: A computer search of Pubmed, Embase, Cochrane library, Web of Science, and Google Scholar databases was conducted for studies investigating ETS and MTS for patients with pituitary adenomas. The deadline is March 01, 2021. RevMan5.1 software was used to complete this meta-analysis after literature screening, data extraction, and literature quality evaluation.

RESULTS: A total of 37 studies including 5,591 patients were included. There was no significant difference in gross tumor removal (GTR) and hormone-excess secretion remission (HES remission) between two groups [RR = 1.10, 95% CI (0.99-1.22), P = 0.07; RR = 1.09, 95% CI (1.00-1.20), P = 0.05]. ETS was associated with lower incidence of diabetes insipidus (DI) [RR = 0.71, 95% CI (0.58-0.87), P = 0.0008], hypothyroidism [RR = 0.64, 95% CI (0.47-0.89), P = 0.007], and septal perforation [RR = 0.32, 95% CI (0.13-0.79), P = 0.01] than those with MTS.

CONCLUSION: This meta-analysis indicated that ETS cannot significantly improve GTR and HES remission. However, ETS could reduce the incidence of DI, hypothyroidism, and septal perforation without increasing the rate of other complications.

SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/prospero/#myprospero, identifier: CRD42021241217.

PMID:35187049 | PMC:PMC8847202 | DOI:10.3389/fsurg.2021.806855

Filed under: Cushing's, pituitary, Treatments | Tagged: , , , | Leave a comment »

Diagnostic pitfalls in Cushing’s disease impacting surgical remission rates; test thresholds and lessons learned in 105 patients

Posted on September 7, 2021 by MaryO

This article was originally published here

J Clin Endocrinol Metab. 2021 Sep 3:dgab659. doi: 10.1210/clinem/dgab659. Online ahead of print.

ABSTRACT

CONTEXT: Confirming a diagnosis of Cushing’s disease (CD) remains challenging yet is critically important before recommending transsphenoidal surgery for adenoma resection.

OBJECTIVE: To describe predictive performance of preoperative biochemical and imaging data relative to post-operative remission and clinical characteristics in patients with presumed CD.

DESIGN, SETTING, PATIENTS, INTERVENTIONS: Patients (n=105; 86% female) who underwent surgery from 2007-2020 were classified into 3 groups: Group A (n=84) pathology-proven ACTH adenoma; Group B (n=6) pathology-unproven but with postoperative hypocortisolemia consistent with CD, and Group C (n=15) pathology-unproven, without postoperative hypocortisolemia. Group A+B were combined as Confirmed CD and Group C as Unconfirmed CD.

MAIN OUTCOMES: Group A+B was compared to Group C regarding predictive performance of preoperative 24-hour urinary free cortisol (UFC), late night salivary cortisol (LNSC), 1mg dexamethasone suppression test (DST), plasma ACTH, and pituitary MRI.

RESULTS: All groups had a similar clinical phenotype. Compared to Group C, Group A+B had higher mean UFC (p<0.001), LNSC(p=0.003), DST(p=0.06), ACTH(p=0.03) and larger MRI-defined lesions (p<0.001). The highest accuracy thresholds were: UFC 72 µg/24hrs; LNSC 0.122 µg/dl, DST 2.70 µg/dl, and ACTH 39.1 pg/ml. Early (3-month) biochemical remission was achieved in 76/105 (72%) patients: 76/90(84%) and 0/15(0%) of Group A+B versus Group C, respectively, p<0.0001. In Group A+B non-remission was strongly associated with adenoma cavernous sinus invasion.

CONCLUSIONS: Use of strict biochemical thresholds may help avoid offering transsphenoidal surgery to presumed CD patients with equivocal data and improve surgical remission rates. Patients with Cushingoid phenotype but equivocal biochemical data warrant additional rigorous testing.

PMID:34478542 | DOI:10.1210/clinem/dgab659

Filed under: Cushing's, Diagnostic Testing, Treatments | Tagged: , , , , | Leave a comment »

Outcomes of endoscopic transsphenoidal surgery for Cushing’s disease

Posted on March 26, 2021 by MaryO

BMC Endocrine Disorders volume 21, Article number: 36 (2021) Cite this article

Abstract

Background

Transsphenoidal surgery (TSS) to resect an adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma is the first-line treatment for Cushing’s disease (CD), with increasing usage of endoscopic transsphenoidal (ETSS) technique. The aim of this study was to assess remission rates and postoperative complications following ETSS for CD.

Methods

A retrospective analysis of a prospective single-surgeon database of consecutive patients with CD who underwent ETSS between January 2012–February 2020. Post-operative remission was defined, according to Endocrine Society Guidelines, as a morning serum cortisol < 138 nmol/L within 7 days of surgery, with improvement in clinical features of hypercortisolism. A strict cut-off of < 50 nmol/L at day 3 post-op was also applied, to allow early identification of remission.

Results

A single surgeon (MJ) performed 43 ETSS in 39 patients. Pre-operative MRI localised an adenoma in 22 (56%) patients; 18 microadenoma and 4 macroadenoma (2 with cavernous sinus invasion). IPSS was carried out in 33 (85%) patients. The remission rates for initial surgery were 87% using standard criteria, 58% using the strict criteria (day 3 cortisol < 50 nmol/L). Three patients had an early repeat ETSS for persistent disease (day 3 cortisol 306-555 nmol/L). When the outcome of repeat early ETSS was included, the remission rate was 92% (36/39) overall. Remission rate was 94% (33/35) when patients with macroadenomas were excluded. There were no cases of CSF leakage, meningitis, vascular injury or visual deterioration. Transient and permanent diabetes insipidus occurred in 33 and 23% following first ETSS, respectively. There was one case of recurrence of CD during the follow-up period of 24 (4–79) months.

Conclusion

Endoscopic transsphenoidal surgery produces satisfactory remission rates for the primary treatment of CD, with higher remission rates for microadenomas. A longer follow-up period is required to assess recurrence rates. Patients should be counselled regarding risk of postoperative diabetes insipidus.

Peer Review reports

Introduction

With an estimated annual incidence of 1.7 per million [1], Cushing’s disease is rare. Untreated, it poses serious complications including osteoporosis, hypertension, dyslipidaemia, insulin resistance, and hypercoagulability [2] and is associated with a 4.8 fold increase in mortality rate [3,4,5]. Patients who are in remission from CD have a mortality rate which decreases towards (although not reaching) that of the general population [6]. Endoscopic transsphenoidal surgery (ETSS) offers patients potential remission from Cushing’s disease, although long term surveillance is required as recurrence rates range from 5 to 22%% [7,8,9,10,11,12].

Since the first report in 1997 [13], the selective removal of an adrenocorticotropic hormone (ACTH)-secreting pituitary adenoma by endoscopic transsphenoidal surgery has gained popularity as the first line treatment for Cushing’s disease. The primary goal of ETSS treatment in Cushing’s disease is to produce disease remission and to provide long-term control, while minimising complications. Remission rates are dependent on tumour size, preoperative MRI, cavernous sinus invasion, intraoperative visualisation of the tumour and pre- and postoperative ACTH and cortisol concentration [11]. Several studies also report pituitary neurosurgeon experience as a major factor for operative success [2, 14, 15].

Reported remission and recurrence rates after TSS for CD vary widely according to the criteria utilised to define remission [11], and in some studies due to limited patient numbers or short follow-up periods. Indeed, there is no clear consensus on how best to define post-operative remission; an early morning serum cortisol concentration < 138 nmol/L (5μg/dl) within 7 days of TSS is quoted in the 2015 Endocrine Society Clinical Practice Guideline as indicative of remission [16]. A more strict day 3 cut-off of 50 nmol/L (1.8 μg/dl) has been reported in paediatric studies [17], and also included in the Endocrine Society Guideline [16]; the literature suggests this cut-off is associated with remission, and a low recurrence rate of approximately 10% at 10 years [14]. The main objective of this study was to assess the outcomes of endoscopic transsphenoidal surgery for Cushing’s disease in a tertiary pituitary centre; remission using two widely accepted criteria [16], recurrence and postoperative complications.

Methods

Study design

This is a retrospective analysis of a prospectively-maintained database of patients operated on by a single neurosurgeon (MJ), via image-guided endoscopic transsphenoidal approach for Cushing’s disease. Patient data was gathered over 8 years (January 2012 to February 2020) and identified from the institution’s prospective database. Clinical and biochemical data during the follow-up period was reviewed. Approval was granted by the Hospital Audit Committee.

Study population

Patients were screened for Cushing’s syndrome by the presence of typical clinical features, together with failure to adequately suppress cortisol to < 50 nmol/L following overnight dexamethasone suppression test (ONDST) and/or elevated late night salivary cortisol (LNSF) concentration and/or elevated 24 h urinary free cortisol measurements. As per standard guidelines, Cushing’s disease was diagnosed on the basis of elevated serum ACTH measurements, along with confirmatory hormone responses to peripheral corticotropin releasing hormone (CRH) test and inferior petrosal sinus sampling (IPSS). Patients with previous TSS prior to the study period were excluded.

Surgical procedure

A single neurosurgeon subspecialising in endoscopic pituitary and anterior skull base surgery, M.J, carried out all ETSS surgical procedures. The surgical technique has been described in detail in publications by Cappabianca et al. (1998, 1999) and Jho et al. (1997, 2000, 2001) [13, 18,19,20,21]. In summary, the procedure consists of a binostril endoscopic transsphenoidal approach. A selective adenomectomy was performed on patients with adenomas noted on pre-operative MRI. In cases of negative pre-operative MRI, exploration of the pituitary gland was performed. To confirm the diagnosis of ACTH-secreting adenoma or hyperplasia, all specimens removed underwent histopathological and immunohistochemical staining for pituitary hormones.

Postoperative assessment

Patients received empiric oral hydrocortisone on day 1 and on the morning of day 2 post-operatively, prior to assessment of 0800 h serum cortisol on day 3. A blood sample for serum cortisol was drawn at 0800 h on the morning of day 3, if clinically stable, prior to administration of hydrocortisone. The Endocrine Society Clinical Practice Guideline define post-operative biochemical remission as morning serum cortisol < 138 nmol/L (5μg/dl) within 7 days postoperatively [16], ‘standard criteria’. In our institution, we also apply a biochemical cut-off of < 50 nmol/L (1.8 μg/dl) at day 3 postoperatively to allow early indication of biochemical remission, ‘strict criteria’. If serum cortisol on day 3 is 50–138 nmol/L, serial measurements are taken daily to determine if cortisol will fall further, and assessment for improvement/resolution of clinical sequalae of hypercortisolaemia made (such as improvement in blood pressure or glycaemic control), before repeat endoscopic transsphenoidal surgery is considered.

Transient cranial diabetes insipidus (DI) was defined as the development of hypotonic polyuria postoperatively requiring at least one dose of desmopressin [22], which resolved prior to discharge. Permanent DI was confirmed by water deprivation test according to standard criteria [23]. Thyroid stimulating hormone (TSH) deficiency was defined by low fT4 with either low or inappropriately normal TSH. Growth hormone (GH) deficiency was confirmed using either Insulin Tolerance Test or Glucagon Stimulation Test [24]. Gonadotrophin deficiency was defined in premenopausal women as amenorrhoea with inappropriately low FSH and LH concentration, and in postmenopausal patients as inappropriately low FSH and LH concentration.

Recovery of hypothalamic-pituitary-adrenal axis was assessed by short synacthen (250 μg) test or insulin tolerance test 3 months post-operatively, and every 3–6 months thereafter in cases of initial fail or borderline result. Patients were assessed annually for recurrence of Cushing’s disease, recurrence was defined by failure to suppress cortisol to < 50 nmol/L following an 1 mg overnight dexamethasone suppression test, an elevated late night salivary cortisol (LNSF) or urinary free cortisol (UFC) in patients no longer taking hydrocortisone.

Laboratory analysis

Prior to 2019, serum cortisol was measured using a chemiluminescent immunoassay with the Beckman Coulter UniCel Dxl 800. Intra-assay CV for serum cortisol was 8.3, 5 and 4.6% at concentrations of 76, 438 and 865 nmol/L, respectively. From January 2019 onwards, serum cortisol was measured using Elecsys® Cortisol II assay on the Roche Cobas e801; intra-assay precision for serum cortisol was 1.2, 1.1 and 1.6% at concentrations of 31.8, 273 and 788 nmol/L, respectively.

Statistics

Data are expressed as median (range) and number (%). The Fishers Exact test was used to compare categorical variables between groups. All p-values were considered statistically significant at a level < 0.05. Statistical analysis was performed using GraphPad Prism 8 statistical software (GraphPad Software, La Jolla, California, USA).

Results

Demographics

Forty-three endoscopic transsphenoidal procedures were performed in 39 patients. Demographics are summarised in Table 1. Median (range) age was 37 years (8–75), 30 were female. Median (range) duration of symptoms was 24 months (6–144), 72% (28/39) had hypertension, and 28% (11/39) had type 2 diabetes.

Table 1 Summary of demographics and post-operative outcomes
Full size table

Preoperative imaging and IPSS

Pre-operative MRI localised an adenoma in 22 (56%) patients; 18 microadenoma and 4 macroadenoma (2 with cavernous sinus invasion). No adenoma was identified in 17 patients (44%). IPSS was carried out in 33 (85%) patients.

Postoperative remission

Post-operative outcomes are summarised in Table 1 and Fig. 1. Using standard criteria (0800 h serum cortisol < 138 nmol/l within 7 days of operation and improvement in clinical features of hypercortisolism), postoperative remission rates for initial surgery were 87% (34/39) for the entire group and 89% (31/35) when patients with macroadenomas were excluded, Fig. 1. Three patients had an early repeat ETSS for persistent disease; day 3 serum cortisol ranged from 306 to 555 nmol/L and interval to repeat ETSS from 10 days–3 months. When the outcome of early repeat ETSS was factored in, overall remission rate was 92% (36/39) overall, and 94% (33/35) when patients with macroadenomas were excluded.

Fig. 1
figure1

Schema of patients who underwent ETSS. *Day 3 cortisol was not measured in one patient due to intercurrent illness requiring treatment with intravenous glucocorticoids

Full size image

Using strict criteria of early remission (day 3 serum cortisol concentration < 50 nmol/L), postoperative remission rates were 58% (22/38) overall, and 62% (21/34) excluding macroadenomas. Including the three patients with early repeat ETSS, remission rate was 61% (23/38) overall, and 65% excluding macroadenomas (22/34). Day 3 cortisol was not measured in one patient due to intercurrent illness requiring treatment with intravenous glucocorticoids.

Eleven patients (28%) had a cortisol measurement between 50 and 138 nmol/L on day 3, seven of whom had received metyrapone therapy prior to ETSS. Six patients had serial measurements of 0800 h cortisol up to a maximum follow-up of 14 days post-op, serum cortisol concentration fell after day 3 in all six patients. Ten (91%) were glucocorticoid-dependent at 3 months based on synacthen/ITT; 0800 h cortisol had fallen to < 50 nmol/L in six patients.

Predictors of remission

No statistical difference was found in the rates of remission in those patients with or without tumour target on preoperative MRI, using either strict criteria for remission (12/21 target vs 10/17 no target, p > 0.99) or standard criteria (19/22 target vs 15/17 no target, p > 0.99). Similar results were found when the four patients with macroadenoma were excluded.

Persistent disease

Five patients (13%) had persistent hypercortisolaemia after the initial endoscopic transsphenoidal surgery (Table 2). Three patients underwent a repeat early endoscopic transsphenoidal surgery, Fig. 1. Remission rate after repeat early ETSS was 67% (2/3) using standard criteria, and 33% (1/3), using the strict criteria. Of the patients with persistent disease following repeat ETSS, one received radiosurgery, while the other has been commenced on medical therapy, with a view to refer for radiotherapy.

Table 2 Outcome of five patients with persistent hypercortisolaemia after initial ETSS
Full size table

Postoperative complications

The rate of transient diabetes insipidus after first ETSS was 33% (13/39), while permanent diabetes insipidus occurred in 23% (9/39). Postoperatively, there were five cases of new thyroid stimulating hormone deficiency (13%) and four cases of gonadotrophin deficiency (10%) (in pre-menopausal females). There were no cases of postoperative CSF leak, no cases of meningitis and no visual complications. There were no other complications.

Recurrence

No patients were lost to follow-up. Over a median (range) duration of follow-up of 24 (4–79) months, one patient had recurrence of Cushing’s disease. Pre-operative MRI had shown a macroadenoma; serum cortisol on day 3 after the initial ETSS was 71 nmol/L, which fulfilled standard criteria for remission, but not the more strict criteria. The patient underwent a second ETSS 13 months later. No tumour was visible intra-operatively so no tissue was removed, day 3 serum cortisol concentration was 308 nmol/L and the patient was commenced on a trial of metyrapone.

Recovery of the hypothalamic-pituitary-adrenal axis

Recovery of the hypothalamic-pituitary-adrenal axis occurred in nine patients (27%), at median 13 (3–27) months post-operatively. There was no statistical difference in rates of recovery of HPA axis in patients with day 3 cortisol < 50 nmol/l, and those who only passed standard criteria for remission (< 138 nmol/l) [7/20 (follow-up 25 (3–59) months) versus 2/11 (follow-up 16 (3–79) months) respectively, p = 0.43]. One patient died 5 weeks post-operatively; post-mortem revealed bilateral haemorrhagic adrenal necrosis.

Discussion

Reported remission rates following ETSS in patients with Cushing’s disease (CD) vary widely, predominantly due to differences in criteria used to define remission [11]. There is no uniform consensus on the criteria used to define ‘remission’, with institutions using a combination of biochemical and clinical criteria; this makes comparing surgical outcome studies challenging. The normal corticotroph cells of the pituitary gland are suppressed due to sustained hypercortisolaemia, therefore following successful removal of the ACTH-secreting adenoma, serum ACTH and cortisol concentrations should fall postoperatively. A morning serum cortisol concentration < 138 nmol/L (5 μg/dl) within 7 days of ETSS is usually indicative of remission, and this biochemical cut-off is quoted in the Endocrine Society Clinical Practice Guideline [16], and many surgical outcome studies [8, 11, 25]. Other studies have applied a more strict serum cortisol cut-off of < 50 nmol/L (1.8 μg/L) at day 3 postoperatively to allow early indication of biochemical remission [10, 11, 26,27,28]; the literature suggests this cutoff is associated with remission, and a low recurrence rate of approximately 10% at 10 years [14]. Our practice is to apply this latter approach; if serum cortisol on day 3 is 50–138 nmol/L, serial measurements are taken daily to determine if cortisol will fall further, and assessment for improvement/resolution of clinical signs of hypercortisolaemia made, before repeat endoscopic transsphenoidal surgery is considered. It is important to ensure that serum cortisol has reached a nadir, before further intervention is considered.

In this single-centre single-surgeon study, we report two very different remission rates using these two widely accepted criteria. Our remission rate, including those patients who had an early second ETSS, using standard guidelines, is 92%, on par with other larger studies [7, 8, 11, 25, 29]. When patients with corticotroph macroadenomas were excluded, the remission rate was even higher at 94%. In comparison, when we applied the more strict criteria of day 3 cortisol < 50 nmol/L, the remission rate was considerably lower at 61%. This criteria is in place in our institution so that we can safely identify patients who have early signs of remission to facilitate discharge on day 3 post-operatively; however reporting these rates in isolation lead to a misleadingly low remission rate compared to the more lenient criteria proposed by the Endocrine Society [16].

Evidence has suggested that higher day 3 cortisol concentration is associated with greater risk of recurrence of CD. A recent retrospective cohort analysis of 81 ETSS for CD by Mayberg et al. reported significantly higher recurrence rates in patients with post-operative cortisol nadir between 58 and 149 nmol/L (2.1–5.4 μg/dL) compared with those with cortisol < 55 nmol/L (2 μg/dL) (33% vs 6%, p = 0.01) [30]. Recurrence of CD was low in our series at 3%, and occurred in a patient with a corticotroph macroadenoma, which have been shown to be associated with higher rates of recurrence [31]. On post-operative assessment, serum cortisol fell between the two criteria for remission and if remission was strictly defined as a day 3 cortisol < 50 nmol/L, then this patient had in fact persistent hypercortisolaemia. This case highlights the difficulty when comparing studies reporting ETSS outcomes in CD – the distinction between persistent post-operative hypercortisolism and early recurrence of CD is not always clear-cut, and is dictated by the local protocol.

Whilst our recurrence data are encouraging in comparison to other reports on CD recurrence, which published rates of up to 22% [11], longer term follow-up is necessary before recurrence rates can be accurately defined. The criteria used to define long term recurrence of CD also varies widely in the literature; a large systematic review (n = 6400) by Petersenn et al. (2015) reported decreased recurrence rates when studies used UFC with ONDST vs. UFC only, and UFC with morning serum cortisol vs. UFC only [11]. This highlights the requirement for standardization of remission and recurrence criteria, for consistency in clinical practice and in the literature.

The post-operative surgical complication rate in our series was very low, with no cases of CSF leak, vascular injury or visual compromise. Other published case series have reported incidence rates for CSF leakage and meningitis of 0–7.2% and 0–7.9% [2, 12, 32, 33] respectively. Postoperative meningitis is strongly associated with CSF leakage [34]. Some studies suggest that the endoscopic approach results in higher rates of carotid artery injury compared with the microscopic approach, which could be attributed to the nature of the extended lateral approach [35]. However, in this series of 43 ETSS, we report no cases of surgical related carotid artery injury, similar to other studies reporting 0% serious morbidity or mortality due to carotid artery injury [33, 36]. Finally, postoperative visual disturbance is a major concern, as it can be life changing for patients. Factors linked with visual complications include tumour size, patient age and any pre-existing visual conditions [37,38,39]. Visual deterioration after TSS for Cushing’s disease has been reported to occur in some large case series at rates of 1.9% [32] and 0.86% [12]. There were no cases of postoperative visual disturbance in our series.

While the surgical complication rate was low, our endocrine complication rate was higher than that reported in other studies, particularly the rate of DI. Transient DI occurred in 33% of cases, and permanent DI in 23%. These relatively high rates of transient DI may be due to the diagnostic criteria used in our protocol; we defined transient post-operative DI as one episode of hypotonic polyuria in the setting of normal or elevated plasma sodium concentration, requiring at least one dose of desmopressin. In contrast, some studies discount any polyuria which lasts less than 2 days [10], while others require the documentation of hypernatremia for the diagnosis of DI [40]. These more stringent criteria will not capture cases of mild transient DI; therefore it is not surprising that the rates of transient DI reported in a 2018 meta-analysis were lower than that in our study, 11.3% [29]. The rates of permanent DI in our study merits particular attention. TSS for CD has been shown to be associated with a higher risk of post-operative DI [41, 42]. It may be that a more aggressive surgical approach resulted in high remission rates, but at a cost of higher rates of DI. All patients are reviewed post-operatively in the National Pituitary Centre, where there is a low threshold for water deprivation testing and/or 3% saline testing. We did not routinely re-test patients for resolution of DI after their initial water deprivation test at 3 months, and it is possible that some cases subsequently resolved after 3 months [41, 43]. Regardless, the rate reported in this study is significant, and emphasises the importance of counselling the patient about the risk of DI long-term.

Strengths and limitations

The reporting of two remission rates based on widely accepted criteria is a strength of this study, and allows for direct comparison of our outcomes with other studies. All ETSS were performed by a single pituitary surgeon; while this removes bias from surgeon experience, the disadvantage of this is that the sample size is relatively low. Furthermore, because we included patients who were recently operated on to maximise numbers for analysis of surgical complications, the follow-up period is relatively short. A longer follow-up is required to comment accurately on recurrence of CD. We did not have full ascertainment of longitudinal post-operative data including dexamethasone suppression tests, and this has highlighted the need for protocolised follow-up to allow for consistency when reporting our results.

Conclusion

Endoscopic transsphenoidal surgery in patients with Cushing’s disease offers excellent remission rates and low morbidity. Remission rates are much higher when standard criteria [morning serum cortisol < 138 nmol/L (5μg/dl) within 7 days postoperatively] are used compared with day 3 cortisol < 50 nmol/l. Higher remission rates were found for patients with microadenomas. Patients should be counselled regarding risk of post-operative endocrine deficiencies, in particular permanent diabetes insipidus. Longer follow-up is required to accurately assess recurrence rates.

Availability of data and materials

The data that support the findings of this study are not publicly available due to restrictions by General Data Protection Regulation (GDPR), but are available from the corresponding author on reasonable request.

Abbreviations

TSS:
Transsphenoidal surgery
ACTH:
Adrenocorticotropic hormone
CD:
Cushing’s disease
ETSS:
Endoscopic transsphenoidal surgery
ONDST:
Overnight dexamethasone suppression test
LNSF:
Late night salivary cortisol
CRH:
Corticotropin releasing hormone
IPSS:
Inferior petrosal sinus sampling
DI:
Diabetes insipidus
TSH:
Thyroid stimulating hormone
GH:
Growth hormone
UFC:
Urinary free cortisol

References

  1. 1.

    Lindholm J, Juul S, Jorgensen JO, et al. Incidence and late prognosis of cushing’s syndrome: a population-based study. J Clin Endocrinol Metab. 2001;86(1):117–23.

    CAS PubMed PubMed Central Google Scholar

  2. 2.

    Broersen LHA, van Haalen FM, Biermasz NR, et al. Microscopic versus endoscopic transsphenoidal surgery in the Leiden cohort treated for Cushing’s disease: surgical outcome, mortality, and complications. Orphanet J Rare Dis. 2019;14(1):64.

    PubMed PubMed Central Article Google Scholar

  3. 3.

    Hammer GD, Tyrrell JB, Lamborn KR, et al. Transsphenoidal microsurgery for Cushing’s disease: initial outcome and long-term results. J Clin Endocrinol Metab. 2004;89:6348–57.

    CAS PubMed Article PubMed Central Google Scholar

  4. 4.

    Nieman LK. Cushing’s syndrome: update on signs, symptoms and biochemical screening. Eur J Endocrinol/Eur Fed Endoc Soc. 2015;173:M33–8.

    CAS Article Google Scholar

  5. 5.

    Swearingen B, Biller BM, Barker FG, et al. Long-term mortality after transsphenoidal surgery for Cushing disease. Ann Intern Med. 1999;130:821–4.

    CAS PubMed Article PubMed Central Google Scholar

  6. 6.

    Clayton RN, Jones PW, Reulen RC, et al. Mortality in patients with Cushing’s disease more than 10 years after remission: a multicentre, multinational, retrospective cohort study. Lancet Diabetes Endocrinol. 2016;4(7):569–76.

    PubMed Article PubMed Central Google Scholar

  7. 7.

    Berker M, Işikay I, Berker D, et al. Early promising results for the endoscopic surgical treatment of Cushing’s disease. Neurosurg Rev. 2014;37:105–14.

    Article Google Scholar

  8. 8.

    Cebula H, Baussart B, Villa C, et al. Efficacy of endoscopic endonasal transsphenoidal surgery for Cushing’s disease in 230 patients with positive and negative MRI. Acta Neurochir. 2017;159(7):1227–36.

    PubMed Article PubMed Central Google Scholar

  9. 9.

    Shimon I, Ram Z, Cohen ZR, et al. Transsphenoidal surgery for Cushing’s disease: endocrinological follow-up monitoring of 82 patients. Neurosurgery. 2002;51(1):57–62.

    PubMed Article PubMed Central Google Scholar

  10. 10.

    Wagenmakers MA, Boogaarts HD, Roerink SH, et al. Endoscopic transsphenoidal pituitary surgery: a good and safe primary treatment option for Cushing’s disease, even in case of macroadenomas or invasive adenomas. Eur J Endocrinol. 2013;169(3):329–37.

    CAS PubMed Article PubMed Central Google Scholar

  11. 11.

    Petersenn S, Beckers A, Ferone D, et al. Therapy of endocrine disease: outcomes in patients with Cushing’s disease undergoing transsphenoidal surgery: systematic review assessing criteria used to define remission and recurrence. Eur J Endocrinol. 2015;172(6):R227–39.

    CAS PubMed Article PubMed Central Google Scholar

  12. 12.

    Atkinson AB, Kennedy A, Wiggam MI, et al. Long-term remission rates after pituitary surgery for Cushing’s disease: the need for long-term surveillance. Clin Endocrinol. 2005;63:549–59.

    Article Google Scholar

  13. 13.

    Jho HD, Carrau RL. Endoscopic endonasal transsphenoidal surgery: experience with 50 patients. J Neurosurg. 1997;87(1):44–51.

    CAS PubMed Article PubMed Central Google Scholar

  14. 14.

    Biller BM, Grossman AB, Stewart PM, et al. Treatment of adrenocorticotropin-dependent Cushing’s syndrome: a consensus statement. J Clin Endocrinol Metab. 2008;93:2454–6.

    CAS PubMed PubMed Central Article Google Scholar

  15. 15.

    Ciric I, Ragin A, Baumgartner C, et al. Complications of transsphenoidal surgery: results of a national survey, review of the literature, and personal experience. Neurosurgery. 1997;40(2):225–36.

    CAS PubMed Article PubMed Central Google Scholar

  16. 16.

    Nieman LK, Biller BM, Findling JW, et al. Treatment of Cushing’s syndrome: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2015;100(8):2807–31.

    CAS PubMed PubMed Central Article Google Scholar

  17. 17.

    Storr H, Alexandraki K, Martin L, et al. Comparisons in the epidemiology, diagnostic features and cure rate by transsphenoidal surgery between paediatric and adult-onset Cushing’s disease. Eur J Endocrinol. 2011;164(5):667–74.

    CAS PubMed Article PubMed Central Google Scholar

  18. 18.

    Cappabianca P, Alfieri A, de Divitiis E. Endoscopic endonasal transsphenoidal approach to the Sella: towards functional endoscopic pituitary surgery (FEPS). Minim Invasive Neurosurg. 1998;41(2):66–73.

    CAS PubMed Article PubMed Central Google Scholar

  19. 19.

    Cappabianca P, Alfieri A, Thermes S, et al. Instruments for endoscopic endonasal transsphenoidal surgery. Neurosurgery. 1999;45(2):392–6.

    CAS PubMed Article PubMed Central Google Scholar

  20. 20.

    Jho H. Endoscopic transsphenoidal surgery. J Neuro-Oncol. 2001;54:187–95.

    CAS Article Google Scholar

  21. 21.

    Jho HD, Alfieri A. Endoscopic transsphenoidal pituitary surgery: various surgical techniques and recommended steps for procedural transition. Br J Neurosurg. 2000;14(5):432–40.

    CAS PubMed Article PubMed Central Google Scholar

  22. 22.

    Seckl J, Dunger D. Postoperative diabetes insipidus. Br Med J. 1989;298:2.

    CAS Article Google Scholar

  23. 23.

    Garrahy A, Moran C, Thompson CJ. Diagnosis and management of central diabetes insipidus in adults. Clin Endocrinol. 2019;90(1):23–30.

    Article Google Scholar

  24. 24.

    Glynn N, Agha A. Diagnosing growth hormone deficiency in adults. Int J Endocrinol. 2012;2012:972617.

    PubMed PubMed Central Article CAS Google Scholar

  25. 25.

    Starke RM, Reames DL, Chen CJ, et al. Pure endoscopic transsphenoidal surgery for Cushing’s disease: techniques, outcomes, and predictors of remission. Neurosurgery. 2013;72:240–7.

    PubMed Article PubMed Central Google Scholar

  26. 26.

    McCance DR, Besser M, Atkinson AB. Assessment of cure after transsphenoidal surgery for Cushing’s disease. Clin Endocrinol. 1996;44:1–06.

    CAS Article Google Scholar

  27. 27.

    Trainer PJ, Lawrie HS, Verhelst J, et al. Transsphenoidal resection in Cushing’s disease: undetectable serum cortisol as the definition of successfuI treatment. Clin Endocrinol. 1993;38:73–8.

    CAS Article Google Scholar

  28. 28.

    Yap LB, Turner HE, Adams CBT, et al. Undetectable postoperative cortisol does not always predict long-term remission in Cushing’s disease: a single Centre audit. Clin Endocrinol. 2002;56:25–31.

    CAS Article Google Scholar

  29. 29.

    Broersen LHA, Biermasz NR, van Furth WR, et al. Endoscopic vs. microscopic transsphenoidal surgery for Cushing’s disease: a systematic review and meta-analysis. Pituitary. 2018;21(5):524–34.

    PubMed PubMed Central Article Google Scholar

  30. 30.

    Mayberg M, Reintjes S, Patel A, et al. Dynamics of postoperative serum cortisol after transsphenoidal surgery for Cushing’s disease: implications for immediate reoperation and remission. J Neurosurg. 2018;129(5):1268–77.

    PubMed Article PubMed Central Google Scholar

  31. 31.

    Patil CG, Prevedello DM, Lad SP, et al. Late recurrences of Cushing’s disease after initial successful transsphenoidal surgery. J Clin Endocrinol Metab. 2008;93:358–62.

    CAS PubMed Article PubMed Central Google Scholar

  32. 32.

    Fahlbusch R, Buchfelder M, Müller OA. Transsphenoidal surgery for Cushing’s disease. J R Soc Med. 1986;79(5):262–9.

    CAS PubMed PubMed Central Article Google Scholar

  33. 33.

    Sarkar S, Rajaratnam S, Chacko G, et al. Pure endoscopic transsphenoidal surgery for functional pituitary adenomas: outcomes with Cushing’s disease. Acta Neurochir. 2016;158(1):77–86.

    PubMed Article PubMed Central Google Scholar

  34. 34.

    Magro E, Graillon T, Lassave J, et al. Complications related to the endoscopic Endonasal Transsphenoidal approach for nonfunctioning pituitary macroadenomas in 300 consecutive patients. World Neurosurg. 2016;89:442–53.

    PubMed Article PubMed Central Google Scholar

  35. 35.

    Ammirati M, Wei L, Ciric I. Short-term outcome of endoscopic versus microscopic pituitary adenoma surgery: a systematic review and meta-analysis. J Neurol Neurosurg Psychiatry. 2013;84(8):843–9.

    PubMed Article PubMed Central Google Scholar

  36. 36.

    Dehdashti AR, Gentili F. Current state of the art in the diagnosis and surgical treatment of Cushing disease: early experience with a purely endoscopic endonasal technique. Neurosurg Focus. 2007;23:E9.

    PubMed Article PubMed Central Google Scholar

  37. 37.

    Barzaghi LR, Medone M, Losa M, et al. Prognostic factors of visual field improvement after trans-sphenoidal approach for pituitary macroadenomas: review of the literature and analysis by quantitative method. Neurosurg Rev. 2012;35(3):369–78.

    PubMed Article PubMed Central Google Scholar

  38. 38.

    Mortini P, Losa M, Barzaghi R, et al. Results of transsphenoidal surgery in a large series of patients with pituitary adenoma. Neurosurgery. 2005;56(6):1222–33.

    PubMed Article PubMed Central Google Scholar

  39. 39.

    Nomikos P, Buchfelder M, Fahlbusch R. Current management of prolactinomas. J Neuro-Oncol. 2001;54(2):139–50.

    CAS Article Google Scholar

  40. 40.

    Mamelak AN, Carmichael J, Bonert VH, et al. Single-surgeon fully endoscopic endonasal transsphenoidal surgery: outcomes in three-hundred consecutive cases. Pituitary. 2013;16(3):393–401.

    PubMed Article PubMed Central Google Scholar

  41. 41.

    Hensen J, Henig A, Fahlbusch R, et al. Prevalence, predictors and patterns of postoperative polyuria and hyponatraemia in the immediate course after transsphenoidal surgery for pituitary adenomas. Clin Endocrinol. 1999;50:431–9.

    CAS Article Google Scholar

  42. 42.

    Nemergut EC, Zuo Z, Jane JA Jr, et al. Predictors of diabetes insipidus after transsphenoidal surgery: a review of 881 patients. J Neurosurg. 2005;103(3):448–54.

    PubMed Article PubMed Central Google Scholar

  43. 43.

    Adams JR, Blevins LS Jr, Allen GS, et al. Disorders of water metabolism following transsphenoidal pituitary surgery: a single institution’s experience. Pituitary. 2006;9(2):93–9.

    PubMed Article PubMed Central Google Scholar

Filed under: Cushing's, pituitary, Treatments | Tagged: , | Leave a comment »

Cortisol Levels Predict Remission in Cushing’s Patients Undergoing Transsphenoidal Surgery

Posted on September 25, 2019 by MaryO

In patients with Cushing’s disease, removing the pituitary tumor via an endoscopic transsphenoidal surgery (TSS) leads to better remission rates than microscopic TSS, according to new research.

But regardless of surgical approach, plasma cortisol levels one day after surgery are predictive of remission, researchers found.

The study, “Management of Cushing’s disease: Changing trend from microscopic to endoscopic surgery,” was published in the journal World Neurosurgery.

Because it improves visualization and accessibility, endoscopic TSS has been gaining popularity over microscopic TSS to remove pituitary tumors in Cushing’s disease patients. Yet, although this surgery has been associated with high remission rates, whether it outperforms microscopic surgery and determining the factors affecting long-term outcomes may further ease disease recurrence after TSS.

A team with the All India Institute of Medical Sciences addressed this topic in 104 patients who underwent surgery from January 2009 to June 2017. Among these patients, 47 underwent microscopic surgery and 55 endoscopic surgery. At presentation, their ages ranged from 9 to 55 (mean age of 28). Also, patients had been experiencing Cushing’s symptoms over a mean duration of 24 months.

Eighty-seven patients showed weight gain. Hypertension (high blood pressure) and diabetes mellitus were among the most common co-morbidities, found in 76 and 33 patients, respectively. Nineteen patients had osteoporosis and 12 osteopenia, which refers to lower-than-normal bone mineral density.

As assessed with magnetic resonance imaging, 68 patients had a microadenoma (a tumor diameter smaller than one centimeter) and 27 had a macroadenoma (a tumor one centimeter or larger). Only two patients had an invasive pituitary adenoma.

Two patients with larger tumors were operated on transcranially (through the skull). The surgery resulted in total tumor removal in 90 cases (86.5%). A blood loss greater than 100 milliliter was more common with endoscopic than with microscopic TSS.

Ten patients developed transient diabetes inspidus, two experienced seizures after surgery, and six of nine patients with macroadenoma and visual deterioration experienced vision improvements after TSS.

The incidence of intraoperative leak of cerebrospinal fluid — the liquid surrounding the brain and spinal cord — was 23.2%, while that of post-operative leak was 7.7% and was more common in microadenoma than macroadenoma surgery (9.8% vs. 5.0%).

Seventeen patients were lost to follow-up and two died due to metabolic complications and infections. The average follow-up was shorter for endoscopic than with microscopic surgery (18 months vs. 35 months).

Among the remaining 85 cases, 65 (76.5%) experienced remission, as defined by a morning cortisol level under 5.0 μg/dL, restored circadian rhythm (the body’s internal clock, typically impaired in Cushing’s patients), and suppression of serum cortisol to below 2 μg/dl after overnight dexamethasone suppression test.

The remission rate was 54.5% in pediatric patients and was higher with endoscopic than with microscopic TSS (88.2% vs. 56.6%). Also, patients with microadenoma showed a trend toward more frequent remission than those with macroadenoma (73.2% vs. 64.3%).

Ten of the remaining 20 patients experienced disease recurrence up to 28 months after surgery. Sixteen cases revealed signs of hypopituitarism, or pituitary insufficiency, which were managed with replacement therapy.

A subsequent analysis found that morning cortisol level on day one after surgery was the only significant predictor of remission. Specifically, a one-unit increase in cortisol lowered the likelihood of remission by 7%. A cortisol level lower than 10.7 μgm/dl was calculated as predicting remission.

Overall, the study showed that “postoperative plasma cortisol level is a strong independent predictor of remission,” the researchers wrote, and that “remission provided by endoscopy is significantly better than microscopic approach.”

From https://cushingsdiseasenews.com/2019/09/24/cortisol-levels-predict-remission-cushings-patients-undergoing-transsphenoidal-surgery/

Filed under: Cushing's, pituitary, Treatments | Tagged: , , , , , , , , , , | Leave a comment »

Next Page »
%d bloggers like this: