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

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 [12]. 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 [37-9]. Additionally, there is evidence that glucocorticoids act by way of negative feedback to suppress AVP secretion [1011-20]. 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 [729].

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 [3031]; 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 [12], and there is evidence that glucocorticoids act by way of negative feedback to suppress AVP secretion [1011-20]. 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 [2637-40], 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.

Sparsely Granulated Corticotroph Pituitary Macroadenoma Presenting with Pituitary Apoplexy Resulting in Remission of Hypercortisolism

https://doi.org/10.1016/j.aace.2022.04.003Get rights and content
Under a Creative Commons license
Open access

Highlights

• We describe a rare case of a patient with a sparsely granulated corticotroph pituitary macroadenoma with pituitary apoplexy who underwent transsphenoidal resection resulting in remission of hypercortisolism.
• Corticotroph adenomas are divided into densely granulated, sparsely granulated and Crooke’s cell tumors.
• macroadenomas account for 7-23% of patients with pituitary corticotroph adenomas
• Sparsely granulated corticotroph tumors are associated with longer duration of Cushing disease prior to diagnosis, larger tumor size at diagnosis, decreased immediate remission rate, increased proliferative marker Ki-67 and increased recovery time of hypothalamic-pituitary-adrenal axis after surgery.
• Granulation pattern is an important clinicopathological distinction impacting the behavior and treatment outcomes of pituitary corticotroph adenomas

Abstract

Background

/Objective: Pituitary corticotroph macroadenomas, which account for 7% to 23% of corticotroph adenomas, rarely present with apoplexy. The objective of this report is to describe a patient with a sparsely granulated corticotroph tumor (SGCT) presenting with apoplexy and remission of hypercortisolism.

Case Report

A 33-year-old male presented via ambulance with sudden onset of severe headache and nausea/vomiting. Physical exam revealed bitemporal hemianopsia, diplopia from right-sided third cranial nerve palsy, abdominal striae, facial plethora, dorsal and supraclavicular fat pad. Magnetic resonance imaging (MRI) demonstrated a 3.2 cm mass arising from the sella turcica with hemorrhage compressing the optic chiasm, extension into the sphenoid sinus and cavernous sinus. Initial investigations revealed plasma cortisol of 64.08 mcg/dL (Reference Range (RR), 2.36 – 17.05). He underwent emergent transsphenoidal surgery. Pathology was diagnostic of SGCT. Post-operatively, cortisol was <1.8ug/dL (RR, 2.4 – 17), adrenocorticotropic hormone (ACTH) 36 pg/mL (RR, 0 – 81), thyroid stimulating hormone (TSH) 0.07 uIU/mL (RR, 0.36 – 3.74), free thyroxine 1 ng/dL (RR, 0.8 – 1.5), luteinizing hormone (LH) <1 mIU/mL (RR, 1 – 12), follicle stimulating hormone (FSH) 1 mIU/mL (RR, 1 – 12) and testosterone 28.8 ng/dL (RR, 219.2 – 905.6) with ongoing requirement for hydrocortisone, levothyroxine, testosterone replacement and continued follow-up.

Discussion

Corticotroph adenomas are divided into densely granulated, sparsely granulated and Crooke’s cell tumors. Sparsely granulated pattern is associated with larger tumor size and decreased remission rate after surgery.

Conclusion

This report illustrates a rare case of hypercortisolism remission due to apoplexy of a SGCT with subsequent central adrenal insufficiency, hypothyroidism and hypogonadism.

Keywords

pituitary apoplexy
pituitary macroadenoma
pituitary tumor
sparsely granulated corticotroph tumor
Cushing disease

Introduction

The incidence of Cushing Disease (CD) is estimated to be between 0.12 to 0.24 cases per 100,00 persons per year1,2. Of these, 7-23% are macroadenomas (>1 cm)345. Pituitary apoplexy is a potentially life-threatening endocrine and neurosurgical emergency which occurs due to infarction or hemorrhage in the pituitary gland. Apoplexy occurs most commonly in non-functioning macroadenomas with an estimated prevalence of 6.2 cases per 100,000 persons and incidence of 0.17 cases per 100,00 persons per year6. Corticotroph macroadenoma presenting with apoplexy is uncommon with only a handful of reports in the literature7. We present a case of a sparsely granulated corticotroph (SGCT) which presented with apoplexy leading to remission of hypercortisolism and subsequent central adrenal insufficiency.

Case Presentation

A 33-year-old male who was otherwise healthy and not on any medications presented to a community hospital with sudden and severe headache accompanied by hypotension, nausea, vomiting, bitemporal hemianopsia and diplopia. Computed Tomography (CT) scan of the brain demonstrated a hyperattenuating 2.0 cm x 2.8 cm x 1.5 cm mass at the sella turcica with extension into the right cavernous sinus and encasement of the right internal carotid arteries (Figure 1A). He was transferred to a tertiary care center for neurosurgical management with endocrinology consultation post-operatively.

  1. Download : Download high-res image (404KB)
  2. Download : Download full-size image

Figure 1. hyperattenuating 2.0 cm x 2.8 cm x 1.5 cm mass at the sella turcica on unenhanced CT (A); MRI demonstrated a 1.9 cm x 3.2 cm x 2.4 cm heterogeneous mass on T1 (B) and T2-weighted imaging (C) showing small hyperintense areas in solid part of the sella mass with flattening of the optic chiasm, remodeling/dehiscence of the floor of the sella and extending into the right cavernous sinus with at least partial encasement of the ICA

In retrospect, he reported a 3-year history of ongoing symptoms of hypercortisolism including increased central obesity, dorsal and supraclavicular fat pad, facial plethora, abdominal purple striae, easy bruising, fatigue, decreased libido and erectile dysfunction. Notably, at the time of presentation he did not have a history of diabetes, hypertension, osteoporosis, fragility fractures or proximal muscle weakness. He fathered 2 children previously. His physical examination was significant for Cushingoid facies, facial plethora, dorsal and supraclavicular fat pads and central obesity with significant axillary and abdominal wide purple striae (Figure 2). Neurological examination revealed bitemporal hemianopsia, right third cranial nerve palsy with ptosis and impaired extraocular movement. The fourth and sixth cranial nerves were intact as was the rest of his neurological exam. These findings were corroborated by Ophthalmology.

  1. Download : Download high-res image (477KB)
  2. Download : Download full-size image

Figure 2. Representative images illustrating facial plethora (A); abdominal striae (B, C); supraclavicular fat pad (D); dorsal fat pad (E)

Initial laboratory data at time of presentation to the hospital included elevated plasma cortisol of 64.08ug/dL (RR, 2.36 – 17.05), ACTH was not drawn at the time of presentation, normal TSH 0.89 mIU/L (RR, 0.36 – 3.74), free thyroxine 0.91ng/dL (RR, 0.76 – 1.46), evidence of central hypogonadism with low total testosterone 28.8 ng/dL (RR, 219.2 – 905.6) and inappropriately normal luteinizing hormone (LH) 1mIU/mL (RR, 1 – 12) and follicle stimulating hormone (FSH) 3mIU/mL (RR, 1 – 12), low prolactin <1 ng/mL (RR, 3 – 20), and normal insulin growth factor – 1 (IGF–1) 179ng/mL (RR, 82 – 242).

A pituitary gland dedicated MRI was performed to further characterize the mass, which re-demonstrated a 1.9 cm x 3.2 cm x 2.4 cm heterogenous mass at the sella turcica extending superiorly and flattening the optic chiasm, remodeling of the floor of the sella and bulging into the sphenoid sinus and extending laterally into the cavernous sinus with encasement of the right internal carotid artery (ICA). As per the radiologist’s diagnostic impression, this appearance was most in keeping with a pituitary macroadenoma with apoplexy (Figure 1B – C).

The patient underwent urgent TSS and decompression with no acute complications. Pathological examination of the pituitary adenoma showed features characteristic of sparsely granulated corticotroph pituitary neuroendocrine tumor (adenoma)8, with regional hemorrhage and tumor necrosis (apoplexy). The viable tumor exhibited a solid growth pattern (Figure 3A), t-box transcription factor (T-pit) nuclear immunolabeling (Figure 3B), diffuse cytoplasmic CAM5.2 (low molecular weight cytokeratin) immunolabeling (Figure 3C), and regional weak to moderate intense granular cytoplasmic ACTH immuno-staining (Figure 3D). The tumor was immuno-negative for: pituitary-specific positive transcription factor 1 (Pit-1) and steroidogenic factor 1 (SF-1) transcription factors, growth hormone, prolactin, TSH, FSH, LH, estrogen receptor-alpha, and alpha-subunit. Crooke hyalinization was not identified in an adjacent compressed fragment of non-adenomatous anterior pituitary tissue. Ki-67 immunolabeling showed a 1.5% proliferative index (11 of 726 nuclei).

  1. Download : Download high-res image (2MB)
  2. Download : Download full-size image

Figure 3. Hematoxylin phloxine saffron staining showing adenoma with solid growth pattern (A); immunohistochemical staining showing T-pit reactivity of tumor nuclei (B); diffuse cytoplasmic staining for cytokeratin CAM5.2 (C); and regional moderately intense granular cytoplasmic staining for ACTH (D). Scale bar = 20 μm

Post-operatively, he developed transient central diabetes insipidus requiring desmopressin but resolved on discharge. His postoperative cortisol was undetectable, ACTH 36 pg/mL (RR, 0 – 81), TSH 0.07 mIU/mL (RR, 0.36 – 3.74), free thyroxine 1 ng/dL (RR, 0.8 – 1.5), LH <1mIU/mL (RR, 1 – 12), FSH 1 mIU/mL (RR, 1 – 12) and testosterone 28.8 ng/dL (RR, 219.2 – 905.6) (Table 1 and Figure 4). One month later, he reported 15 pounds of weight loss and a 5-inch decrease in waist circumference. He also noted a reduction in the dorsal and supraclavicular fat pads, facial plethora, and Cushingoid facies as well as fading of the abdominal stretch marks. His visual field defects and right third cranial nerve palsy resolved on follow up with ophthalmology post-operatively. Repeat MRI six months post-operatively showed minor residual soft tissue along the floor of the sella. He is being followed by Neurosurgery, Ophthalmology, and Endocrinology for monitoring of disease recurrence, visual defects, and management of hypopituitarism.

Table 1. Pre- and post-operative hormonal panel

POD -1 POD 0 POD1 POD2 POD3 POD16 6 -9 months Comments
Cortisol(2.4 – 17 ug/dL) 64↓ 32↓ 11↓ <1.8↓ <1.8↓ 1.8↓ HC started POD3 post bloodwork
ACTH(0 – 81 pg/mL) 41↓ 36↓ 28↓ 13↓
TSH(0.36 – 3.74 uIU/mL) 0.89 0.43 0.12↓ 0.07↓ 0.05↓ 0.73
Thyroxine, free(0.8 – 1.5 ng/dL) 0.9 0.9 1.1 1 2.1↑ 1 Levothyroxine started POD4
LH(1 – 12 miU/mL) 1↓ <1↓ 1↓ 3
FSH(1 – 12 mIU/mL) 3↓ 1↓ 1↓ 3
Testosterone(219.2 – 905.6 ng/dL) 28.8↓ <20↓ 175.9↓ Testosterone replacement started as outpatient
Testosterone, free(160 – 699 pmol/L) <5.8↓ 137↓
IGF-1(82 – 242 ng/mL) 179 79
GH(fasting < 6 mIU/L) 4.5 <0.3
Prolactin(3 – 20 ng/mL) <1↓ <1↓

POD, postoperative day; HC, hydrocortisone; ACTH, adrenocorticotropic hormone; TSH, thyroid stimulating hormone; LH, luteinizing Hormone; FSH, follicle stimulating hormone; IGF-1, insulin like growth factor – 1; GH, growth hormone

  1. Download : Download high-res image (259KB)
  2. Download : Download full-size image

Figure 4. Trend of select pituitary hormonal panel with key clinical events denoted by black arrows.

Discussion

Microadenomas account for the majority of corticotroph tumors, but 7% – 23% of patients are diagnosed with a macroadenoma345. It is even rarer for a corticotroph macroadenoma to present with apoplexy with only a handful of case reports or series in the literature7. Due to its rarity, appropriate biochemical workup on presentation, such as including an ACTH with the blood work, may be omitted especially if the patient is going for emergent surgery. In this case, the undetectable prolactin can reflect loss of anterior pituitary function and also suggest a functioning corticotroph adenoma due to the inhibitory effect of long term serum glucocorticoids on prolactin secretion9. After undergoing TSS, the patient developed central adrenal insufficiency, hypothyroidism and hypogonadism requiring hormone replacement. Presumably, the development of adrenal insufficiency demonstrated the remission of hypercortisolism as a result of apoplexy and/or TSS. The ACTH remains detectable likely representing residual tumor that was not obliterated by apoplexy nor excised by TSS given it location near the carotid artery and cavernous sinus. The presence of adrenal insufficiency in the setting of detectable ACTH is not contradictory as the physiological hypothalamic-pituitary-adrenal axis has been suppressed by the long-term pathological production of ACTH. IGF-1 and prolactin also failed to recover post-operatively. In CD where the production of IGF-1 and prolactin are attenuated by elevated cortisol, it would then be expected that IGF-1 and prolactin recover after hypercortisolism remission. However, the absence of this observation in our case is likely a sequalae of the apoplexy and extensive surgery leading to pituitary hypofunction.

We also want to highlight features of the pre-operative radiographical findings which can provide valuable insight into the subsequent histology. Previous literature has shown that, on T2-weight MRI, silent corticotroph adenomas are strongly correlated with characteristic a multimicrocystic appearance while nonfunctional gonadotroph macroadenomas are not correlated with this MRI finding10. The multimicrocystic appearance is described as small hyperintense areas with hyperintense striae in the solid part of the tumor (Figure 1C)10. This is an useful predictive tool for silent corticotroph adenomas with a sensitivity of 76%, specificity of 95% and a likelihood ratio of 15.310.

The ability to distinguish between silent corticotroph macroadenoma and other macroadenomas is important for assessing rate of remission and recurrence risk. In 2017, the WHO published updated classification for pituitary tumors. In this new classification, corticotroph adenomas are further divided into densely granulated, sparsely granulated and Crooke’s cell tumors11. DGCT are intensely Periodic Acid Schiff (PAS) stain positive and exhibit strong diffuse pattern of ACTH immunoreactivity, whereas SGCT exhibit faintly positive PAS alongside weak focal ACTH immunoreactivity4,12. Crooke’s cell tumors are characterized by Crooke’s hyaline changes in more than 50% of the tumor cells4. In the literature, SGCT account for an estimated 19-29% of corticotroph adenomas131415. The clinicopathological relevance of granulation pattern in corticotroph tumors was unclear until recently.

In multiple studies examining granulation pattern and tumor size, SGCT were statistically larger13,15,16. Hence, we suspect that many of the previously labelled silent corticotroph macroadenomas in the literature were SGCT. The traditional teaching of CD has been “small tumor, big Cushing and big tumor, small Cushing” which reflects the inverse relationship between tumor size and symptomatology17. This observation appears to hold true as Doğanşen et al. found a trend towards longer duration of CD in SGCT of 34 months compared to 26 months in DGCT based on patient history13,17. It has been postulated that the underlying mechanism of the inverse relationship between tumor size and symptomatology is impaired processing of proopiomelanocortin resulting in less effective secretion of ACTH in corticotroph macroadenomas3. Doğanşen et al. also found that the recurrence rate was doubled for SGCT, while Witek et al. showed that SGCT were less likely to achieve remission postoperatively13,16.

Similar to other cases of SGCT, the diagnosis was only arrived retrospective after pathological confirmation10. Interestingly, the characteristic Crooke’s hyaline change of surrounding non-adenomatous pituitary tissue was not observed as one would expect in a state of prolonged glucocorticoid excess in this case. Although classically described, the absence of this finding does not rule out CD. As evident in a recent retrospective study where 10 out of 144 patients with CD did not have Crooke’s hyaline change18. In patients without Crooke’s hyaline change, the authors found a lower remission rate of 44.4% compared to 73.5% in patients with Crooke’s hyaline change. Together with the detectable post-operative ACTH, sparsely granulated pattern and absence of Crooke’s hyaline change in surrounding pituitary tissue, the risk of recurrence is increased. These risk factors emphasize the importance of close monitoring to ensure early detection of recurrence.

Declaration of Interests

☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

☐The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:

Conclusion

We present a case of a sparsely granulated corticotroph macroadenoma presenting with apoplexy leading to remission of hypercortisolism and development of central adrenal insufficiency, hypothyroidism and hypogonadism requiring hormone replacement.

References

Possible Good News! Effects of Tubastatin A on Adrenocorticotropic Hormone Synthesis and Proliferation of Att-20 Corticotroph Tumor Cells

  • Rie HagiwaraDepartment of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
  • Kazunori KageyamaDepartment of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
  • Yasumasa IwasakiSuzuka University of Medical Science, Suzuka 510-0293, Japan
  • Kanako NiiokaDepartment of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
  • Makoto DaimonDepartment of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Hirosaki 036-8562, Japan
Abstract

Cushing’s disease is an endocrine disorder characterized by hypercortisolism, mainly caused by autonomous production of ACTH from pituitary adenomas. Autonomous ACTH secretion results in excess cortisol production from the adrenal glands, and corticotroph adenoma cells disrupt the normal cortisol feedback mechanism. Pan-histone deacetylase (HDAC) inhibitors inhibit cell proliferation and ACTH production in AtT-20 corticotroph tumor cells. A selective HDAC6 inhibitor has been known to exert antitumor effects and reduce adverse effects related to the inhibition of other HDACs. The current study demonstrated that the potent and selective HDAC6 inhibitor tubastatin A has inhibitory effects on proopiomelanocortin (Pomc) and pituitary tumor-transforming gene 1 (Pttg1) mRNA expression, involved in cell proliferation. The phosphorylated Akt/Akt protein levels were increased after treatment with tubastatin A. Therefore, the proliferation of corticotroph cells may be regulated through the Akt-Pttg1 pathway. Dexamethasone treatment also decreased the Pomc mRNA level. Combined tubastatin A and dexamethasone treatment showed additive effects on the Pomc mRNA level. Thus, tubastatin A may have applications in the treatment of Cushing’s disease.

Access the PDF at https://www.jstage.jst.go.jp/article/endocrj/advpub/0/advpub_EJ21-0778/_pdf/-char/en

 

Increased Risk of Death in Cushing’s Disease Persists After Remission

An analysis of nationwide data from Sweden provides an overview of the increased risk of death associated with Cushing’s disease was present even after biochemical remission.

New data from an analysis of patient data over nearly 30 years suggests the increased risk of mortality associated with Cushing’s disease persists even after treatment.

A 4:1 matched analysis comparing data from 371 patients with Cushing’s disease with 1484 matched controls, indicated risk of mortality was 5-fold greater among those not in remission compared to matched controls, but even those in remission at the last follow-up were at a 50% greater risk of mortality compared to controls.

“To our knowledge, this is the first study that investigated mortality in an unselected cohort of patients treated for Cushing’s disease and followed up in comparison to mortality in matched controls. The mortality rate was more than doubled in patients with Cushing’s disease, and not being in remission was a strong predictor of premature death,” wrote investigators.

With a lack of consensus surrounding the impact of biochemical remission on life expectancy in patients with Cushing’s disease, a team of investigators from multiple institutions in Sweden designed their study with the intent of assessing this association with mortality in a time-to-event analysis of an unselected nationwide Cushing’s disease cohort. Using the Swedish Pituitary Registry, investigators identified 371 patients with Cushing’s disease for inclusion in their analysis.

The Swedish Pituitary Register is a nationwide registry that collected data on the majority of Swedish patients with Cushing’s disease. For the current study, investigators included all patients with Cushing’s disease from the register diagnosed between May 1991-September 2018 and followed these patients until the date of death, date of emigration, or December 26, 2018. From the register, investigators obtained data related to date of diagnosis, age, sex, treatment, and biochemical remission status evaluations.

The median age at diagnosis was 44 (IQR, 32-56) years and the median follow-up was 10.6 (IQR, 5.7-18) years. The remissions rates for the study cohort were 80%, 92%, 96%, 91%, and 97% at the 1-, 5-, 10-, 15- and 20-year follow-ups, respectively. These patients were matched in a 4:1 based on age, sex, and residential area at the diagnosis data, yielding a cohort of 1484 matched controls.

Upon analysis, the overall risk of mortality was greater among those with Cushing’s disease compared to the matched controls (HR, 2.1 [95% CI, 1.5-2.8]). Investigators pointed out increased risk was observed among patients in remission at the last follow-up (n=303; HR, 1.5 [95% CI, 1.02-2.2]), those in remission after a single pituitary surgery (n=177; HR, 1.7 [95% CI, 1.03-2.8]), and those not in remission (n=31; HR, 5.6 [95% CI, 2.7-11.6]). Additionally, results indicated cardiovascular disease and infections were the most overrepresented cases of death, accounting for 32 and 12 of the 66 total instances of mortality.

“The findings of the present study confirm and complement previous findings of increased overall mortality in Cushing’s disease patients, having a more than doubled HR for death compared to matched controls. Most importantly, an increased HR persisted among patients who had been successfully treated and reached a Cushing’s disease biochemical cure,” investigators added.

This study, “Increased mortality persists after treatment of Cushing’s disease: A matched nationwide cohort study,” was published in the Journal of the Endocrine Society.

 

Pregnancy Doesn’t Boost Cushing Disease Recurrences

Researchers published the study covered in this summary on Research Square as a preprint that has not yet been peer reviewed.

Key Takeaways

  • Among women who underwent pituitary surgery to treat Cushing disease subsequent pregnancy had no apparent effect on Cushing disease recurrence, in a single-center review of 113 women treated over a 30-year period.

Why This Matters

  • No single factor predicts the recurrence of Cushing disease during long-term follow-up of patients who have undergone pituitary surgery.
  • This is the first study to assess the effect of pregnancy on Cushing disease recurrence in a group of reproductive-age women who initially showed post-surgical remission.

Study Design

  • Retrospective study of 355 patients with confirmed Cushing disease who were admitted to a single tertiary hospital in Brazil between 1990 and 2020. All patients had transsphenoidal surgery, with a minimum follow-up of 6 months and median follow-up of 83 months. Remission occurred in 246 of these patients.
  • The current analysis focused on 113 of the patients who achieved remission, were women, were 45 years old or younger at time of surgery (median 32 years old), and had information available on their obstetric history.
  • Ninety-one of these women (81%) did not become pregnant after their surgery, and 22 (19%) became pregnant after surgery.

Key Results

  • Among the 113 women in the main analysis 43 (38%) had a Cushing disease recurrence, a median of 48 months after their pituitary surgery.
  • Following surgery, 11 women in each of the two subgroups (recurrence, no recurrence) became pregnant.
  • Although the subgroup with recurrence had a higher incidence of pregnancy (11/43; 26%) compared with those with no recurrence (11/70; 16%) Kaplan-Meier analysis showed that survival free of Cushing disease recurrence was similar and not significantly different in the women with a postsurgical pregnancy and those who did not become pregnant (P=.531).
  • The review also showed that, of the women who became pregnant, several obstetrical measures were similar between patients who had a recurrence and those who remained in remission, including number of pregnancies per patient, maternal weight gain, type of delivery (normal or cesarean), delivery time (term or premature), neonatal weight, and neonatal size. The review also showed roughly similar rates of maternal and fetal complications in these two subgroups of women who became pregnant.

Limitations

  • The study was retrospective and included a relatively small number of patients.
  • The authors collected information on obstetric history for some patients by telephone or email contacts.

Disclosures

  • The study received no commercial funding.
  • None of the authors had disclosures.

This is a summary of a preprint research study ” Pregnancy After Pituitary Surgery Does Not Influence the Recurrence of Cushing s Disease,  written by researchers at the Sao Paulo (Brazil) University Faculty of Medicine on Research Square provided to you by Medscape. This study has not yet been peer reviewed. The full text of the study can be found on researchsquare.com.