Medium and Long-Term Data from a Series of 96 Endoscopic Transsphenoidal Surgeries for Cushing Disease

Objective

Postoperative data on Cushing’s disease (CD) are equivocal in the literature. These discrepancies may be attributed to different series with different criteria for remission and variable follow-up durations. Additional data from experienced centers may address these discrepancies. In this study, we present the results obtained from 96 endoscopic transsphenoidal surgeries (ETSSs) for CD conducted in a well-experienced center.

Methods

Pre- and postoperative data of 96 ETSS in 87 patients with CD were included. All cases were handled by the same neurosurgical team between 2014 and 2022. We obtained data on remission status 3−6 months postoperatively (medium-term) and during the latest follow-up (long-term). Additionally, magnetic resonance imaging (MRI) and pathology results were obtained for each case.

Results

The mean follow-up duration was 39.5±3.2 months. Medium and long-term remission rates were 77% and 82%, respectively. When only first-time operations were considered, the medium- and long-term remission rates were 78% and 82%, respectively. The recurrence rate in this series was 2.5%. Patients who showed remission between 3−6 months had higher longterm remission rates than did those without initial remission. Tumors >2 cm and extended tumor invasion of the cavernous sinus (Knosp 4) were associated with lower postoperative remission rates.

Conclusion

Adenoma size and the presence/absence of cavernous sinus invasion on preopera-tive MRI may predict long-term postoperative remission. A tumor size of 2 cm may be a supporting criterion for predicting remission in Knosp 4 tumors. Further studies with larger patient populations are necessary to support this finding.

Key WordsComplete remission · Neuroendoscopy · Pituitary-dependant Cushing syndrome · Treatment outcome.

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INTRODUCTION

Cushing’s disease (CD) is characterized by excessive secretion of adrenocorticotropic hormone (ACTH) by a corticotropic adenoma in the pituitary gland. In patients with CD whose hypercortisolism is inadequately corrected, morbidity and mortality can increase by up to 4.8 times due to Cushingrelated complications such as osteoporosis, hypertension, dyslipidemia, insulin resistance, and hypercoagulability [11,18].
Endoscopic transsphenoidal surgery (ETSS), the first-line treatment for CD [7], is performed to decrease complications while achieving remission and long-term disease control. Previous studies on CD have reported varying remission rates between 45% and 95% and recurrence rates ranging from 3−66% [2,4,9,16,21,30]. This wide range of differences can be primarily attributed to differences in surgical experience among centers: centers with higher surgical experience have fewer postoperative complications and higher remission rates [4,6]. However, despite initial remission, patients with CD may eventually experience recurrence. The mean recurrence rate at the 5-10-year follow-up is 23% for microadenomas and 33% for macroadenomas [19,23,30].
Since the postoperative rates in the literature are variable, additional data from experienced centers may be necessary to resolve these discrepancies. In this study, we present the medium- and long-term follow-up data from 96 operations for CD that were conducted in a center with a high level of experience for ETSS.
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MATERIALS AND METHODS

The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by the Ethics Committee of Basaksehir Cam and Sakura City Hospital (No. 2022185). Informed consent was obtained from all patients. The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
This retrospective study included pre and postoperative data of 96 ETSS performed in 87 patients with CD (Fig. 1). CD was diagnosed based on unsuppressed cortisol levels (>1.8 µg/dL) following the 1-mg dexamethasone suppression test, high levels of urinary free cortisol, or late night salivary cortisol and plasma ACTH levels >20 pg/mL [28]. Between 2014 and 2022, all surgeries were conducted by the experienced neurosurgical team (Ö.G., O.T., B.E., E.A.) responsible for endoscopic transsphenoidal procedures at the Pituitary Research Center. The surgeries were performed under perioperative glucocorticoid coverage.

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Fig. 1.
Number of operations and patients included in the study.

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Size, cavernous sinus invasion, sellar and suprasellar infiltration of adenoma on preoperative magnetic resonance imaging (MRI) scans, residual tumor on postoperative MRI scans, postoperative complications, pathology results, remission and recurrence status, and additional postoperative management were evaluated in addition to patients’ demographic data. For follow-up assessments, data obtained 3−6 months postoperatively and during the latest follow-up were included. Three different classifications obtained during radiologic evaluation using MRI were used for pituitary adenomas : 1) maximum size of tumor (MST) : 0−5 mm (group 1), 6−10 mm (group 2), 11−20 mm (group 3), and >20 mm (group 4); 2) Knosp classification : for evaluation of cavernous sinus invasion [22]; and 3) modified Hardy classification : for evaluation of sellar and suprasellar infiltrations [20,39].
In cases of CD without a lesion or with a lesion <6 mm on MRI, confirmation of the central origin and lateralization was provided by inferior petrosal sinus sampling (IPSS) with corticotropin-releasing hormone stimulation [25,26,29]. Under neuronavigation guidance, pure ETSS surgical interventions were performed for all patients by a single surgical team using the Medtronic StealthStation S7 and S8 systems (Medtronic, Minneapolis, MN, USA) together with 4-mm 0°, 30°, and 45° rigid optical instruments and an endoscope. A nasal decongestant spray was administered 1 hour before the operation. The sphenoid ostium was detected from both nostrils, and a bi-nostril approach was used by resecting the posterior nasal septum. After sphenoidectomy, the standard sellar approach was used for lesions in the sellar region. The details of these surgical procedures are described in previous study [14]. Selective adenectomy with ETSS was performed for preoperatively localized and visible tumors, whereas hemihypophysectomy was performed for non-lesional cases. In cases with cavernous sinus-invading tumors, particularly Knops 3-4, the defect which was created by the tumor on the medial wall of anterior cavernous sinus was identified and, it was expanded for resection of the tumor tissue within the cavernous sinus. If a defect was not visible, blunt-ended hook-shaped dissectors were used to create a defect on the medial wall, allowing access for the tumor to enter the cavernous sinus. Hematoxylin and Eosin (H&E) and immunohistochemistry staining were performed for the specimens obtained during ETSS. Adenomas showing positive immunohistological staining for ACTH were diagnosed histologically as corticotropinomas.
CD was considered to be in remission when the cases showed basal cortisol levels <5 µg/dL or suppressed cortisol levels (≤1.8 µg/dL) following the 1-mg dexamethasone suppression test, 3-6 months postoperation, and during the latest follow-up. The study protocol was approved by the ethics committee of our institution.
Data were statistically analyzed using the SPSS 15.0 package (IBM Corp., Armonk, NY, USA). The chi-square test was used for categorical variables. Sample distribution was evaluated with the Kolmogorov-Smirnov test. Continuous independent variables with a normal distribution were compared using the Student’s t-test. Continuous variables with non-normal distributions were compared using the Mann-Whitney U test. p<0.05 was considered statistically significant. A Kaplan-Meier survival analysis was conducted to determine probability and time to recurrence in cases with initial remission.
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RESULTS

Demographic data

A total of 96 ETSS were performed for 87 patients with CD. Of the 87 patients, 68 (79%) were female, and 19 (21%) were male. The mean patient age was 42.2±12.9 years, and the mean duration of follow-up was 39.5±3.2 months. Of the 96 surgeries, 79 (82%) were performed for the first time, six (6%) were performed for residual tumors, and 11 (12%) were performed following a recurrence of the disease. Eight of the 17 patients who underwent reoperations had undergone their first operation at another center.

Preoperative imaging

Table 1 shows the maximum tumor size on preoperative pituitary MRI before each surgical procedure. Preoperative IPSS for lateralization was performed in 42 operations (44%), all of which were first-time cases. Knosp classification based on preoperative pituitary MRI and the modified Hardy classification is presented in Table 1.

Table 1.

Preoperative pituitary magnetic resonance imaging scans

Number of tumors (n=96)
Maximum tumor size
 Group 1, 0−5 mm 41 (42.7)
 Group 2, 6−10 mm 24 (25.0)
 Group 3, 11−20 mm 20 (20.8)
 Group 4, >20 mm 11 (11.5)
Knosp classification
 Grade 0 52 (54.2)
 Grade 1 22 (22.9)
 Grade 2 6 (6.3)
 Grade 3 8 (8.3)
 Grade 4 8 (8.3)
Modified Hardy classification
 0
  A 41 (42.8)
  B
  C
  D
  E
 1
  A 14 (14.6)
  B
  C
  D
  E 4 (4.2)
 2
  A 5 (5.2)
  B
  C
  D
  E 5 (5.2)
 3
  A 1 (1.0)
  B 2 (2.1)
  C
  D
  E 1 (1.0)
 4
  A 1 (1.0)
  B
  C
  D 1 (1.0)
  E 3 (3.1)
 NA 18 (18.8)

Values are presented as number (%). Invasion : 0, sella normal; 1, sella focally expanded and tumor ≤10 mm; 2, sella enlarged and tumor ≥10 mm; 3, localized perforation of the sellar floor; 4, diffuse destruction of the sellar floor. Suprasellar extension : A, no suprasellar extension; B, anterior recesses of the third ventricle obliterated; C, floor of the third ventricle grossly displaced with parasellar extension; D, intracranial (intradural) : anterior, middle or middle fossa; E, into/beneath the cavernous sinus (extradural).

NA : not available

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Postoperative results

Remission was achieved between the 3rd and 6th months in 74 (77%) of the 96 operations, and long-term remission in 79 operations (82%). Among all 96 operations, eight (8%) concluded with a residual tumor. Regarding only first-time operations, five (6%) of the 79 concluded with a postoperative residual tumor. Of the 79 first-time operations, there were 62 cases (78%) of remission between 3 and 6 months. Two (2.5%) of these 79 operations involved recurrence during follow-up, while 60 (97%) showed sustained remission. Those with sustained remission had a median disease-free survival time of 31 months (interquartile range, 14-64) during long-term followup, two cases with recurrence had their recurrence 49 and 54 months after their operation. Survival analysis of cases with remisson and recurrence is presented in Fig. 2. CD persisted after 17 (21.5%) of the 79 first operations.

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Fig. 2.
Survival analysis after the first operation in cases with remission at 3-6 months. Dashed line represents cases with recurrence and, straight line represents cases with sustained remission during long-term follow-up.

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Ten (13%) of the 79 cases underwent reoperation; two were due to recurrence, and eight due to disease persistence. In five cases (29%), the patients were initially unresponsive but showed remission later during the long-term follow-up. Remission was achieved with stereotactic radiosurgery (STRS) and medical treatment in one of these cases, with only STRS in two and only medical treatment in two cases. At the latest follow-up visit, the total number of cases showing remission after the first operation was 65 (82%). Additional details regarding the results of the first operations are provided in Fig. 3.

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Fig. 3.
Results of the cases who had operation for the first time.

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Of the 18 reoperations, the results for one case were excluded since the patient was operated at another center. After the reoperation (n=17), the medium and long-term remission rates were 71% (n=12) and 77% (n=13), respectively. The 3-6-month remission rate did not differ significantly between first-time and reoperations (p=0.5). Residual tumors were present in three cases (18%) after reoperation. Of the early non-responders, one case showed remission after STRS, and none of the responders showed recurrence during long-term follow-up. Additional details regarding the results of reoperations are provided in Fig. 4.

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Fig. 4.
Results of the reoperations in our center.

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Remission rates based on tumor size are presented in Table 2. The initial remission rates of the tumors in MST group 4 were significantly lower than those in the other MST groups (MST 1 vs. 4, p=0.01; MST 2 vs. 4, p=0.001; and MST 3 vs. 4, p=0.006). Comparisons of the other MST groups showed no significant differences. When adenomas were stratified using the 10-mm cut-off, the remission rates did not differ significantly (remission rate, 81% for adenomas <10 mm and 68% for adenomas ≥10 mm; p=0.2). Postoperative residual tumors were observed in five of the 11 tumors (46%) >2 cm (MST group 4) and in one tumor in each of MST groups 1-3 (2%, 4%, and 5%, respectively, p<0.001). Reoperation rate was 17% (n=7) for adenomas ≤5 mm, 18% (n=10) for adenomas ≥6 mm (p=0.9), and 27% (n=3) for adenomas >20 mm (among all grades, p=0.3).

Table 2.

Comparison of remission rates in preoperative pituitary magnetic resonance imaging scans

3−6-month remission Long-term remission
Maximum tumor size
 Group 1, 0−5 mm (n=41) 31 (75.6) 33 (80.5)
 Group 2, 6−10 mm (n=24) 22 (91.7) 22 (91.7)
 Group 3, 10−20 mm (n=20) 17 (85.0) 17 (85.0)
 Group 4, >20 mm (n=11) 4 (36.4) 7 (63.6)
p-value 0.003* 0.200
Knops classification
 0 (n=52) 41 (78.8) 44 (84.6)
 1 (n=22) 21 (95.5) 21 (95.5)
 2 (n=6) 4 (66.7) 3 (50.0)
 3 (n=8) 7 (87.5) 7 (87.5)
 4 (n=8) 1 (12.5) 4 (50.0)
p-value <0.001* 0.010*
Modified Hardy classification
 0
  A (n=41) 32 (78.0) 34 (82.9)
 1
  A (n=14) 12 (85.7) 12 (85.7)
 2
  E (n=4) 3 (75.0) 3 (75.0)
  A (n=5) 5 (100.0) 5 (100.0)
 3
  E (n=5) 2 (40.0) 2 (40.0)
  A (n=1) 1 (100.0) 1 (100.0)
  B (n=2) 2 (100.0) 2 (100.0)
 4
  E (n=1) 0 (0.0) 0 (0.0)
  A (n=1) 1 (100.0) 1 (100.0)
  D (n=1) 0 (0.0) 0 (0.0)
  E (n=3) 1 (33.3) 3 (100.0)
p-value 0.10 0.06
Pathology result
 Corticotropinoma (+) (n=71) 58 (81.7) 60 (84.5)
 Corticotropinoma (-) (n=25) 16 (64.0) 19 (76.0)
p-value 0.07 0.30

Values are presented as number (%). Invasion : 0, sella normal; 1, sella focally expanded and tumor ≤10 mm; 2, sella enlarged and tumor ≥10 mm; 3, localized perforation of the sellar floor; 4, diffuse destruction of the sellar floor. Suprasellar extension : A, no suprasellar extension; B, anterior recesses of the third ventricle obliterated; D, intracranial (intradural) with anterior, middle, or middle fossa; E, into/beneath the cavernous sinus (extradural).

* Statistically significant p-value

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Remission rates based on Knosp and Hardy classifications are presented in Table 2, respectively. The medium-term remission rates in Knosp group 4 were significantly lower than the rates in the other groups (Knosp 0 vs. 4, p<0.001; Knosp 1 vs. 4, p<0.001; Knosp 2 vs. 4, p=0.04; and Knosp 3 vs. 4, p=0.003). Additionally, the medium-term remission rate of tumors in Knosp group 2 was lower than that in Knosp group 1 (p=0.04). However, remission rates did not differ significantly among the other groups. Comparing invasive (Knosp 3 and 4) and noninvasive (Knosp 0, 1, and 2) tumors, remission rates within 3-6 months were 50% and 83% in the invasive and noninvasive groups, respectively. We further stratified cases with tumor size ≥20 mm (n=11) using Knosp classification; one case (9%) was Knosp 0, one case (9%) was Knosp 1, two cases (18%) were Knosp 3, and seven cases (64%) were Knosp 4 tumors. For ≥20 mm, all cases with Knosp 0, 1, and 3 tumors achieved remission within 3-6 months postoperatively, while none of the cases with Knosp 4 tumors had remission (p=0.01). All the cases with Knosp 0, 1, and 3 tumors sustained remission, and three cases with Knosp 4 tumor later achieved long-term remission (p=0.3). Of the cases that achieved long-term remission, two underwent STRS, and one had medical therapy with additional STRS.
Of the 96 tissue specimens obtained during ETSS, 71 (74%) stained positive for ACTH and were histologically identified as corticotropic adenomas, while 25 (26%) were negative. Remission rates based on the pathology results are compared in Table 2. Of the lesions with conclusive findings on MRI (≥6 mm lesions), 89% (n=49) were pathologically confirmed as corticotropinomas, whereas 54% (n=22) of those with inconclusive MRI f indings were pathologically conf irmed (p<0.001). Among the lesions that showed negative results for both conclusive MRI findings (≤5 mm) and pathologic confirmation (negative for a corticotropinoma) (n=19), 12 (63%) showed remission at 3-6 months and 14 (74%) showed remission during long-term follow-up.
During the exploration of the cavernous sinus in one patient (1%), postoperative lateral gaze paralysis of the eye developed due to right abducens nerve palsy. The patient was treated with anti-inflammatory doses of steroids, and the symptom completely resolved within 1 month. In three other patients (3%), severe epistaxis was observed in the postoperative period, 1 to 3 weeks after surgery. Nasal packing was applied for 3 days. Additionally, three patients (3%) experienced postoperative rhinorrhea. To address this issue, a reconstruction of the skull base was performed using fat tissue harvested from the leg, fascia lata graft, and tissue adhesive material. These patients were monitored with a lumbar drain for 1 week. Among the patients who developed rhinorrhea, one patient also developed meningitis and received intravenous antibiotic therapy for about 3 weeks and, the situation compeletly resolved during follow-up. The postoperative complications are summarized in Table 3. Comparison of various characteristics of the cases with and without medium and long-term remission are presented in Table 3, respectively.

Table 3.

Comparison of cases with and without remission, postoperative complications

3−6-month remission


Long-term remission


Number of cases (n=96)
Remission (+) (n=74) Remission (-) (n=22) p-value Remission (+) (n=79) Remission (-) (n=17) p-value
Operation 0.500 0.08
 First time 62 (83.8) 17 (77.3) 66 (83.5) 13 (76.5)
 Re-operation 12 (16.2) 5 (22.7) 13 (16.5) 4 (23.5)
Tumor characteristics 0.003* 0.20
 MST
  Grade 1 31 (42.0) 10 (45.0) 33 (41.8) 8 (47.1)
  Grade 2 22 (30.0) 2 (9.0) 22 (27.8) 2 (11.8)
  Grade 3 17 (23.0) 3 (14.0) 17 (21.5) 3 (17.6)
  Grade 4 4 (5.0) 7 (32.0) 7 (8.9) 4 (23.5)
 Knosp classification <0.001* 0.01*
  0 41 (56.0) 11 (50.0) 44 (55.5) 9 (53.0)
  1 21 (28.0) 1 (4.5) 21 (26.5) 2 (12.0)
  2 4 (5.0) 2 (9.0) 3 (4.0) 1 (6.0)
  3 7 (10.0) 1 (4.5) 7 (9.0) 1 (6.0)
  4 1 (1.0) 7 (32.0) 4 (5.0) 4 (23.0)
 Hardy classification 0.09 0.06
  0A 32 (43.2) 9 (41.0) 34 (43.0) 7 (41.0)
  1A 12 (16.2) 2 (9.0) 12 (15.0) 2 (12.0)
  1E 3 (4.0) 1 (4.5) 3 (4.0) 1 (6.0)
  2A 5 (6.7) 0 (0.0) 5 (6.0) 0 (0.0)
  2E 2 (2.7) 3 (14.0) 2 (3.0) 3 (17.0)
  3A 1 (1.4) 0 (0.0) 1 (1.0) 0 (0.0)
  3B 2 (2.7) 0 (0.0) 2 (3.0) 0 (0.0)
  3E 0 (0.0) 1 (4.5) 0 (0.0) 1 (6.0)
  4A 1 (1.4) 0 (0.0) 1 (1.0) 0 (0.0)
  4D 0 (0.0) 1 (4.5) 0 (0.0) 1 (6.0)
  4E 1 (1.4) 2 (9.0) 3 (4.0) 0 (0.0)
  NA 15 (20.3) 3 (13.5) 16 (20.0) 2 (12.0)
Postoperative
 Complication 0.900 0.30
  (+) 10 (13.5) 3 (13.6) 12 (15.2) 1 (5.9)
  (-) 64 (86.5) 19 (86.4) 67 (84.8) 16 (94.1)
 Pathologic diagnosis 0.070 0.30
  Corticotropinoma 58 (78.4) 13 (59.1) 60 (75.9) 11 (64.7)
  Negative 16 (21.6) 9 (40.9) 19 (24.1) 6 (35.3)
 Remission during long-term F/U <0.001*
  (+) 72 (97.3) 7 (31.8)
  (-) 2 (2.7) 15 (68.2)
 Residual tumor 0.001*
  (+) 3 (3.8) 5 (29.4)
  (-) 76 (96.2) 12 (70.6)
 Remission during long-term F/U <0.001*
  (+) 72 (91.1) 2 (11.8)
  (-) 7 (8.9) 15 (88.2)
Postoperative complication
 DI-temporary 4 (4.2)
 DI-permanent 4 (4.2)
 Meningitis 1 (1.0)
 CSF leak 3 (3.1)
 Epistaxis 3 (3.1)
 Cranial nerve palsy, transient 1 (1.0)
Hypopituitarism 4 (4.2)
 Hypocortisolism 2 (2.1)
 Hypothyroidisim 2 (2.1)

Values are presented as number (%). *Statistically significant p-values. MST : maximum size of tumor, NA : not available, F/U : follow up, DI : diabetes insipidus, CSF : cerebrospinal fluid

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DISCUSSION

This study reported an overall postoperative 3-6 month remission rate of 77% and a long-term remission rate of 82% after 3 years of follow-up. The initial and long-term remission rates after first operations were 78% and 82%, respectively, with a recurrence rate of 2.5% over a follow-up period of 3-3.5 years. Additionally, our findings revealed that tumor size >2 cm and extended tumor invasion of the cavernous sinus (Knosp 4) might be associated with lower postoperative remission rates. Patients who showed remission within 3-6 months showed higher rates of long-term remission than those in patients without initial remission.
Pituitary surgery is the first-line treatment modality for CD. ETSS is a safe and less invasive method for treating pituitary adenomas; therefore, it has been increasingly preferred in CD [5,15]. However, the postsurgical outcomes in patients with CD have shown variable remission and recurrence rates [2,4,9,16,17,21,30]. These discrepancies may be attributable to differences in population and number of cases involved in the studies, tumor characteristics, criteria for remission and recurrence used by the centers, laboratory parameters, time of evaluation and followup durations, surgical and imaging techniques used by different centers, and neurosurgical expertise.
In this study, we present the medium- and long-term postoperative results of 96 ETSS procedures performed in 87 patients. The medium-term results (obtained 3-6 months postoperation) were preferred to immediate results since a subset of cases may show delayed remission, and immediate postoperative results could be misleading in almost 6% of cases [37]. The overall medium-term remission rate was 77%, consistent with the results published by Serban et al. [34], who reported an overall remission rate of 77% 2 months postoperation. A larger series of 1106 cases reported an immediate remission rate of 72.5% within 7 days postoperation; however, this rate decreased to 67% after delayed remission rates and recurrences 56 months postoperation were considered [12]. The long-term remission rate obtained over a median period of 3 years was 82% in our series. The increased long-term remission rate was attributed to reoperations, additional medical therapies, and the use of STRS in those who did not show remission initially.
Of the 96 procedures, 79 were performed for the first time. The medium-term remission rate after first operations was 78%. Recent studies have reported remission rates of 74-82% after first operations [12,34]. The recurrence rates reported previously varied between 3% and 66% [5,12,34]. However, the duration of follow-up differed among the studies. Dai et al. [12] and Brady et al. [5] reported recurrence rates of 12% and 3%, respectively, after a follow-up period of 2 years. In contrast, Serban et al. [34] reported a recurrence rate of 17% after a longer followup duration of 6 years. In this series, after a median follow-up period of 3 years, the overall recurrence rate was 2.5%. Residual tumors were observed in five cases (6%), and the reoperation rate after the first operation was 13%. Including the eight patients admitted for reoperation after having undergone their first surgery in another center, 17 cases involved reoperations in our center. Of these cases, 71% (n=12) showed remission between 3-6 months postoperation, while none showed recurrence; thus, the long-term remission rate was 77%. Residual tumors were detected in three cases (18%), and the disease persisted in four (24%) of these 17 reoperated cases. Previous studies have reported remission rates of 22-75% after repeated surgery in CD [5,12,34,38]. Although the success rates after reoperations were lower than those in first-time operations in some studies [38], the remission rates after the first and reoperations did not differ significantly in our study.
Tumor size has been reported to contribute to the success of transsphenoidal surgery [12,34], with microadenomas showing a higher success rate after surgery [5,12,34]. Our remission rates for micro- and macroadenomas were similar to those reported by Dai et al. [12] : 81% for adenomas <10 mm and 68% for adenomas ≥10 mm. However, the statistical significance of our study differed from that in the series presented by Dai et al. [12] (p=0.2 vs. p=0.002). This may be due to the large difference in the number of cases included in the two studies and the differences in size scales for tumors ≥10 mm. In our series, when the tumors were stratified further by the tumor size, the medium-term remission rate further decreased to 36% for tumors ≥20 mm in size, although the remission rates for other groups <20 mm were all above 75% (p=0.003). Sharifi et al. [35] classified pituitary MRI scans in CD showing a tumor size <6 mm as “inconclusive” because incidentalomas are frequent among tumors in this size range, and this size is not indicative of CD. Previously published series reported that the rate of inconclusive MRI scans in CD was 36-64%, and the remission rates varied between 50% and 71% for those with an inconclusive MRI scan [10,24,27,32,33]. In our series, 54% of the preoperative MRI scans were inconclusive. In the series presented by Sharifi et al. [35] and some other series [8,12,32,36], no significant difference was observed between the remission rates of CD cases with and without a conclusive MRI.This finding is controversial since other studies showed decreased remission rates with preoperative inconclusive MRIs [13,40]. Similar to the results reported by Sharifi et al. [35], we did not find a statistically significant difference between the remission rates of tumors <6 mm and those between 6-20 mm. However, a significant difference was observed between tumors <6 mm and those ≥20 mm. Residual tumors were more frequent after operating tumors >20 mm compared to those <20 mm, but the number of reoperations did not differ among the groups. Additionally, tumors >20 mm were primarily Knosp 4 (64%), probably contributing to lower remission rates in this group. Interestingly, two Knosp 3 cases had postoperative remission within 3-6 months without additional intervention. In these two cases, the surgical team explored the cavernous sinus and could resect the tumor. However, complete excision was not feasible with Knosp 4 tumors, where there is a complete encasement of the intracavernous internal carotid artery. Thus, a tumor size of 20 mm may be supportive data in predicting non-remission in the presence of complete cavernous sinus infiltration.
Cavernous sinus invasion, determined by the Knosp classification, and sellar invasion and/or suprasellar extension, determined by the Hardy-Wilson classification, indicate the radiologic status of local invasion in cases of pituitary tumors [20,22,39]. Invasion to surrounding structures and tissues may be a limiting factor for postoperative remission of pituitary tumors. In the series presented by Dai et al. [12], remission rates of corticotropinomas with Knosp grade 4 (definitive cavernous sinus invasion) dropped to 53% from a remission rate of 77% for corticotropinomas with less likely or no cavernous sinus invasion (p<0.001). Similarly, our results showed that both medium- and long-term remission rates for Knosp grade 4 tumors decreased to 13% and 50%, respectively, and were lower than the remission rates in other grades (p<0.001 and p=0.01, respectively). While remission rates in Knosp group 3 were not inferior to noninvasive tumors, remission rates in Knosp group 4 were lower than all the other groups. In this regard, the extent of invasion may be more determinative. In contrast, in our series, the modified Hardy classification did not show a significant effect on postoperative remission rates in medium- and long-term follow-up assessments. Araujo-Castro et al. [3] had previously shown that for pituitary adenomas, the Hardy-Wilson classification lacked utility in predicting postoperative remission compared to the Knosp classification. The difference in the utility of these classifications for predicting postoperative remission may be due to differences in accessing tissues during surgery.
In the present series, 74% (n=71) of tissues were histologically proven to be corticotropinomas, while 26% (n=25) did not show histologic confirmation. Medium- and long-term remission rates did not differ between histologically proven and unproven CD cases (medium-term remission rates, 82% vs. 64%, p=0.07; long-term remission rates, 85% vs. 76%, p=0.3). A conclusive finding of an adenoma on MRI increased the rate of histologic proof of corticotropinoma in our series, implying that adenomas showing a ≥6-mm lesion on MRI more frequently stained positive for ACTH. In previous studies 12-53% of CD did not have postoperative pathologic identification and the rate increased in those with a preoperative inconclusive MRI [25,31,38]. However, this did not have a significant influence on our remission rates. The remission rates did not decrease even for CD cases that were not conclusively detected on MRI and could not be histologically proven. On the other hand, in previous studies, ACTH positivity was higher, and the lack of proof for a corticotropinoma decreased the remission rates [1,12,31,32,34]. The higher remission rates despite reduced localization with MRI and/or lower rates of histologic confirmation in our series may be explained by the successful preoperative IPSS lateralization, surgical exploration, and hemi-hypophysectomy procedure. Furthermore, tumor tissues might have been aspirated along with blood and other materials through the suction tube, potentially resulting in less histological confirmation despite postoperative remission of CD.
Additionally, tumor tissues might have been aspirated along with blood and other materials through the suction tube, potentially resulting in less histological confirmation despite postoperative remission of CD.
The total rate of complications in this series was 20%, and the most frequent complication was diabetes insipidus (DI; 8%, both permanent and temporary). The incidence of hypopituitarism was relatively lower (4%), mainly involving hypocortisolism and hypothyroidism. Recent studies have shown postoperative DI rates of 25-66% and hypothyroidism rates of 11-23% [5,34]. Although our neurosurgical team was experienced in conducting pituitary surgeries, other factors may have resulted in these differences. Since not all the cases were postoperatively followed in our center, with some patients lost to follow-up, there may be missing data.
Comparing cases with and without remission in the medium term, cases of remission frequently involved adenomas >20 mm and less cavernous sinus invasion. Additionally, cases that achieved medium-term remission showed long-term remission more frequently. In the long term, those showing remission had less cavernous sinus invasion and residual tumors compared to those without remission. Therefore, we may conclude that a tumor size of 20 mm may predict medium-term remission, while the absence of/less cavernous sinus invasion, early remission, and absence of residual tumor may predict long-term remission.
This study had limitations. First, the retrospective nature of the study and the limited number of cases, which was inevitable due to the low incidence of CD, may have distorted our results. Although the same neurosurgical team operated on all patients, they were followed up pre and postoperatively at different endocrinology centers, causing difficulty in obtaining the full postoperative data of certain cases. Lastly, some patients recently underwent ETSS; thus, they had a shorter follow-up period. However, we intend to present the longer-term outcomes of all patients in a separate study.
Although ETSS is the first-line treatment for CD, previous studies on the use of ETSS for CD have reported a wide range of remission and recurrence rates, which can be primarily attributed to differences in the surgical experience levels among centers. This trend highlights the need for additional data from experienced centers to resolve the discrepancies in the existing data. Therefore, we present medium- and long-term follow-up data from 96 operations for CD conducted in a center with a high level of experience for ETSS. We believe our study makes a significant contribution to the literature because the findings reconfirm the usefulness of ETSS for the treatment of CD and highlight the importance of the size of the adenoma and presence/absence of cavernous sinus invasion on preoperative MRI in predicting long-term remission postoperatively.
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CONCLUSION

ETSS is a safe and effective method for the treatment of CD. Some characteristics of adenomas, such as size, cavernous sinus invasion, and postoperative residue, may predict long-term remission. A tumor size of 2 cm may be a supporting criterion for predicting remission status in the presence of complete cavernous sinus infiltration. Further studies with larger patient populations are necessary to support this finding.
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Notes

Conflicts of interest

No potential conflicts of interest relevant to this study exist.

Informed consent

Informed consent was obtained from all individual participants included in this study.

Author contributions

Conceptualization : BE, MB, EH; Data curation : EA, OH, DT, MM; Formal analysis : LŞP, DAB, DT, İÇ; Funding acquisition : OT, ÖG, DAB; Methodology : LŞP, İÇ, MM, ÖG; Project administration : BE, SÇ, EH; Visualization : EA, OT, OH; Writing – original draft : BE, MB, SÇ; Writing – review & editing : BE, EH

Data sharing

None

Preprint

None

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Acknowledgements

This manuscript was edited by a certified English Proofreading Service (Editage).
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Navigating the Surgical Landscape: A Comprehensive Analysis of Endoscopic vs. Microscopic Transsphenoidal Pituitary Surgery Outcomes

Abstract

Pituitary surgery, a critical intervention for various pituitary disorders, has sparked ongoing debates regarding the preference between endoscopic and microscopic transsphenoidal approaches. This systematic review delves into the outcomes associated with these techniques, taking into account the recent advancements in neurosurgery. The minimally invasive nature of endoscopy, providing improved visualization and reduced morbidity, stands in contrast to the well-established track record of the conventional microscopic method. Examining outcomes for disorders such as Cushing’s disease and acromegaly, the review synthesizes evidence from Denmark, Bulgaria, and China. Noteworthy advantages of endoscopy encompass higher resection rates, shorter surgery durations, and fewer complications, endorsing its effectiveness in pituitary surgery. While emphasizing the necessity for prospective trials, the review concludes that endoscopic approaches consistently showcase favorable outcomes, influencing the ongoing discourse on the optimal surgical strategies for pituitary disorders.

Introduction & Background

Pituitary surgery is a critical intervention for various pituitary disorders, and the choice between endoscopic and microscopic transsphenoidal approaches has been a subject of ongoing debate within the medical community. This systematic review aims to explore and analyze the outcomes associated with endoscopic and microscopic transsphenoidal pituitary surgery. As advancements in surgical techniques continue to shape the field of neurosurgery, understanding the comparative effectiveness of these two approaches becomes imperative. The endoscopic approach, characterized by its minimally invasive nature, has gained popularity for pituitary surgery in recent years [1]. Proponents argue that it provides enhanced visualization, improved maneuverability, and reduced patient morbidity. On the other hand, traditional microscopic transsphenoidal surgery has been the conventional method for decades, known for its familiarity among surgeons and established track record [2].

Several studies have investigated the outcomes of these approaches in treating pituitary disorders, including but not limited to Cushing’s disease, pituitary adenomas, and other tumors. For instance, a systematic review and meta-analysis by Chen et al. compared endoscopic and microscopic transsphenoidal surgery specifically for Cushing’s disease, shedding light on the effectiveness of these approaches in managing this specific condition [3]. Moreover, Møller et al. reported promising results for endoscopic pituitary surgery based on the experiences of experienced microscopic pituitary surgeons, indicating a potential shift towards the adoption of the endoscopic technique [1]. Guo et al. conducted a meta-analysis comparing the effectiveness of microscopic and endoscopic surgery for treating pituitary disorders, contributing valuable insights into the overall efficacy of these approaches [4].

This review aims to contribute to the ongoing discourse on pituitary surgery by providing a comprehensive analysis of the outcomes associated with endoscopic versus microscopic transsphenoidal approaches. By synthesizing the existing evidence, we strive to offer valuable insights that can guide both clinicians and researchers in making informed decisions regarding the optimal surgical approach for pituitary disorders.

Review

Materials and methods

This systematic review strictly adheres to the established Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, employing a comprehensive approach to investigate the outcomes of endoscopic versus microscopic transsphenoidal pituitary surgery. The subsequent sections delineate the criteria for study inclusion, the search strategy utilized, and the methodology employed for data synthesis.

Search Strategy

We conducted a meticulous search across prominent electronic databases, including PubMed, Embase, and the Cochrane Library, to identify pertinent articles. Our search strategy comprised a combination of Medical Subject Headings (MeSH) terms and keywords related to pituitary surgery, encompassing both endoscopic and microscopic approaches. Boolean operators (AND, OR) were strategically employed to refine the search and identify studies meeting our predetermined inclusion criteria. The search string used for PubMed was (“Outcomes” OR “Treatment Outcome” OR “Surgical Outcome”) AND (“Endoscopic Transsphenoidal Pituitary Surgery” OR “Endoscopic Pituitary Surgery” OR “Endoscopic Hypophysectomy”) AND (“Microscopic Transsphenoidal Pituitary Surgery” OR “Microscopic Pituitary Surgery” OR “Microscopic Hypophysectomy” OR “Endoscopy”[Mesh] OR “Endoscopy, Surgical”[Mesh] OR “Transsphenoidal Hypophysectomy”[Mesh] OR “Microsurgery”[Mesh] OR “Microscopic Hypophysectomy”[Mesh]).

Eligibility Criteria

Stringent inclusion criteria were predefined to ensure the selection of high-quality and relevant studies. The included studies focused on investigating the outcomes of endoscopic versus microscopic transsphenoidal pituitary surgery. Only articles published in peer-reviewed journals within the timeframe from the inception of relevant databases until October 2023 were considered. Exclusion criteria encompassed studies on other interventions, those lacking sufficient data on surgical outcomes, and studies solely involving animal cells. Additionally, only studies in the English language with full-text availability were included, and gray literature was not considered eligible.

Data Extraction and Synthesis

Two independent reviewers meticulously screened titles and abstracts to identify potentially eligible studies. Subsequently, full-text articles were retrieved and evaluated for adherence to inclusion criteria. Discrepancies between reviewers were resolved through discussion and consultation with a third reviewer. Relevant data, including study design, patient characteristics, interventions, and surgical outcomes, were systematically extracted using a predefined data extraction form.

Data Analysis

A narrative synthesis approach was employed to summarize findings from included studies due to anticipated heterogeneity in study designs and outcome measures. Key themes and patterns related to the outcomes of endoscopic versus microscopic transsphenoidal pituitary surgery were identified and presented.

Results

Study Selection Process

Following four database searches, 97 articles were initially identified. After eliminating eight duplicates, the titles and abstracts of the remaining 89 publications were evaluated. Subsequently, 17 potential studies underwent eligibility verification through a thorough examination of their full texts. Ultimately, three articles satisfied the inclusion criteria. No additional studies meeting the eligibility criteria were found during the examination of references in the selected articles. The entire process is visually depicted in the PRISMA flowchart (Figure 1).

PRISMA-flow-diagram-of-the-selection-of-studies-for-inclusion-in-the-systematic-review.
Figure 1: PRISMA flow diagram of the selection of studies for inclusion in the systematic review.

PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses

Characteristics of Selected Studies

Overall, three papers met the inclusion criteria. Two studies were randomized controlled trials (RCTs), one each from Bulgaria and China. One study was an observational study from Denmark. The main findings and characteristics of the included studies are mentioned in the following tables (Table 1 and Table 2).

Author Year Country Study type Sample size No. of participants in the endoscopic group No. of participants in the microscopic group Main findings
Møller et al. [1] 2020 Denmark Observational study 240 45 195 The study comparing endoscopic and microscopic transsphenoidal pituitary surgery revealed that the endoscopic technique exhibited advantages, achieving a higher rate of gross total resection (39% vs. 22%) and shorter surgery duration (86 minutes vs. 106 minutes). Complications within 30 days were lower with the endoscope (17% vs. 27%), and grade II complications or higher were significantly reduced (4% vs. 20%) compared to the microscopic approach. Pituitary function outcomes favored the endoscope, with fewer new deficiencies in the HPA axis (3% vs. 34%) and TSH-dependent deficiencies (15% vs. 38%). The HPG axis also showed better normalization in the endoscopic group (32% vs. 19%). Visual field impairment and postoperative improvement did not significantly differ between the two techniques. Overall, the findings suggest that endoscopic transsphenoidal pituitary surgery may offer superior outcomes compared to the microscopic approach, particularly in terms of resection rates and complication profiles.
Vassilyeva et al. [5] 2023 Bulgaria RCT 83 43 40 The study compared endoscopic and microscopic transsphenoidal pituitary surgery in acromegaly patients, revealing comparable demographic profiles between the groups. Endoscopic surgery demonstrated advantages with shorter anesthesia and surgery times, as well as a reduced postoperative hospital stay. Complete tumor removal was more frequent with endoscopic adenomectomy, while microscopic surgery showed a higher rate of sub-total removal. Both techniques led to a tendency for somatic improvement, with more pronounced visual function improvement in the endoscopic group. Complications, such as liquorrhea and endocrine disorders, were generally low, with endoscopic surgery showing mainly mild complications. Disease remission rates were similar between the groups at various follow-up intervals. In conclusion, while both techniques proved effective in achieving remission, endoscopic surgery exhibited favorable outcomes in terms of efficiency and some aspects of complication profiles.
Zhang et al. [6] 2021 China RCT 46 23 23 Endoscopic transsphenoidal pituitary surgery for the treatment of Cushing’s disease showed comparable efficacy to microscopic transseptal pituitary surgery but with the added benefits of shorter operative time, reduced estimated blood loss, shorter hospital stays, and fewer complications.
Table 1: Summary of the studies included in this systematic review.

RCT: randomized controlled trial; HPA: hypothalamic-pituitary-adrenal; TSH: thyroid-stimulating hormone; HPG: hypothalamic-pituitary-gonadal

Technique Møller et al. [1] Vassilyeva et al. [5] Zhang et al. [6]
Male-to-female ratio (endoscopic) 25:20 17:26 13:10
Male-to-female ratio (microscopic) 107:88 16:24 12:11
Mean age in years (endoscopic) 61 43.26 55.6
Mean age in years (microscopic) 58 44.12 53.2
Functional tumors (endoscopic) 15 All functional All functional
Non-functional tumors (endoscopic) 29
Functional tumors (microscopic) 69 All functional All functional
Non-functional tumors (microscopic) 115
Microadenoma size (mm) (endoscopic) 4 19
Macroadenoma size (mm) (endoscopic) 39 4
Microadenoma size (mm) (microscopic) 3 18
Macroadenoma size (mm) (microscopic) 37 5
Mean operative time (min) (endoscopic) 86 142 108
Mean operative time (min) (microscopic) 106 176 174
Mean hospital stay (days) (endoscopic) 5 2.8
Mean hospital stay (days) (microscopic) 7 5.1
Postoperative complications (endoscopic) 2 15 3
Postoperative complications (microscopic) 39 10 8
Table 2: Summary of demographics, tumor characteristics, and postoperative outcomes of the studies included in this systematic review.

The quality assessment of the selected studies was done using the Newcastle-Ottawa Quality Assessment Scale. All three studies included in this study turned out to be of high quality with a rating of 9/9 stars (Table 3).

Author Selection Comparability Outcome Total stars
Møller et al. [1] ★★★★ ★★ ★★★ ★★★★★★★★★
Vassilyeva et al. [5] ★★★★ ★★ ★★★ ★★★★★★★★★
Zhang et al. [6] ★★★★ ★★ ★★★ ★★★★★★★★★
Table 3: Quality assessment of the included studies using the Newcastle-Ottawa Quality Assessment Scale.

Discussion

This systematic review thoroughly assesses the effectiveness and results of endoscopic transsphenoidal pituitary surgery in comparison to microscopic transsphenoidal surgery, with a specific focus on pituitary adenomas, including Cushing’s disease and acromegaly. The results contribute significant insights into the evolving landscape of pituitary surgery, highlighting the benefits and limitations of both surgical techniques.

The selected studies offer valuable insights into the comparative outcomes. Møller et al.’s observational study in Denmark suggests that endoscopic surgery exhibits superior outcomes with higher gross total resection rates, shorter surgery duration, and fewer complications [1]. Vassilyeva et al.’s RCT in Bulgaria, focusing on acromegaly patients, indicates endoscopic advantages such as shorter anesthesia and surgery times, reduced postoperative stay, and comparable remission rates [5]. Zhang et al.’s RCT in China, specifically for Cushing’s disease, suggests comparable efficacy with added benefits favoring endoscopy [6].

The endoscopic approach has been advocated for its panoramic visualization and superior mobility, which are crucial in resecting tumors while preserving normal structures [7,8]. Studies have shown a higher remission rate in endoscopic procedures for endocrine-active tumors, like growth hormone or adrenocorticotropic hormone (ACTH)-secreting adenomas, compared to the microscopic approach [9,10]. Patient comfort and recovery play a significant role in evaluating surgical methods. The endoscopic technique, by avoiding submucosal excision of nasal tissues, typically results in less postoperative pain and rhinological dysfunction. Studies, including ours, have reported shorter operative times and hospital stays with endoscopic surgery, attributed to fewer intraoperative and postoperative complications and a reduced need for wound management [11-13].

Safety is paramount to any surgical intervention. The endoscopic method has shown a decrease in common complications such as cerebrospinal fluid (CSF) leak, pituitary hormone dysfunction, and diabetes insipidus. Additionally, the endoscopic procedure exhibited fewer complications, which could be attributed to the enhanced visualization allowing for more precise tumor excision and preservation of vital structures [14-16].

In the context of acromegaly patients, the endoscopic technique has demonstrated increased radicality in tumor removal. Our review aligns with these findings, showing a higher rate of total tumor resection in endoscopic patients compared to those undergoing microscopic surgery. This improved outcome is likely due to better illumination and a wider angle of vision provided by endoscopic operations [5,17].

The endoscopic technique has shown a statistically significant improvement in visual function post surgery compared to the microscopic method. However, the frequency of certain postoperative complications, such as intraoperative liquorrhea, was higher in microscopic surgery. These differences underline the importance of the surgical technique in influencing the outcomes and complications of pituitary surgery [5,18].

Despite these findings, it is important to recognize the limitations inherent in these studies. Factors such as tumor size, density, and localization significantly influence surgical outcomes and procedure times. Additionally, the retrospective nature of many studies introduces potential biases, underscoring the need for more prospective, randomized trials for a comprehensive understanding of the long-term outcomes of these techniques.

Conclusions

This systematic review comparing endoscopic and microscopic transsphenoidal pituitary surgery outcomes indicates consistent evidence favoring the endoscopic approach. Notable studies from Denmark, Bulgaria, and China reveal superior results with endoscopic surgery, demonstrating higher resection rates, shorter surgery duration, and fewer complications. Endoscopy’s benefits extend to patient comfort, as evidenced by shorter operative times and hospital stays. Safety considerations also support endoscopy, showing a decrease in common complications such as CSF leaks and hormonal dysfunction. Despite these strengths, the review underscores the need for prospective, randomized trials to address limitations and provide a comprehensive understanding of long-term outcomes.

References

  1. Møller MW, Andersen MS, Glintborg D, Pedersen CB, Halle B, Kristensen BW, Poulsen FR: Endoscopic vs. microscopic transsphenoidal pituitary surgery: a single centre study. Sci Rep. 2020, 10:21942. 10.1038/s41598-020-78823-z
  2. Gao Y, Zhong C, Wang Y, et al.: Endoscopic versus microscopic transsphenoidal pituitary adenoma surgery: a meta-analysis. World J Surg Oncol. 2014, 12:94. 10.1186/1477-7819-12-94
  3. Chen J, Liu H, Man S, et al.: Endoscopic vs. microscopic transsphenoidal surgery for the treatment of pituitary adenoma: a meta-analysis. Front Surg. 2022, 8:806855. 10.3389/fsurg.2021.806855
  4. Guo S, Wang Z, Kang X, Xin W, Li X: A meta-analysis of endoscopic vs. microscopic transsphenoidal surgery for non-functioning and functioning pituitary adenomas: comparisons of efficacy and safety. Front Neurol. 2021, 12:614382. 10.3389/fneur.2021.614382
  5. Vassilyeva N, Mena N, Kirov K, Diatlova E: Comparative effectiveness of endoscopic and microscopic adenoma removal in acromegaly. Front Endocrinol (Lausanne). 2023, 14:1128345. 10.3389/fendo.2023.1128345
  6. Zhang T, Zhang B, Yuan L, Song Y, Wang F: Superiority of endoscopic transsphenoidal pituitary surgery to microscopic transseptal pituitary surgery for treatment of Cushing’s disease. Rev Assoc Med Bras (1992). 2021, 67:1687-91. 10.1590/1806-9282.20210732
  7. Yadav Y, Sachdev S, Parihar V, Namdev H, Bhatele P: Endoscopic endonasal trans-sphenoid surgery of pituitary adenoma. J Neurosci Rural Pract. 2012, 3:328-37. 10.4103/0976-3147.102615
  8. Louis RG, Eisenberg A, Barkhoudarian G, Griffiths C, Kelly DF: Evolution of minimally invasive approaches to the sella and parasellar region. Int Arch Otorhinolaryngol. 2014, 18:S136-48. 10.1055/s-0034-1395265
  9. Broersen LH, Biermasz NR, van Furth WR, de Vries F, Verstegen MJ, Dekkers OM, Pereira AM: Endoscopic vs. microscopic transsphenoidal surgery for Cushing’s disease: a systematic review and meta-analysis. Pituitary. 2018, 21:524-34. 10.1007/s11102-018-0893-3
  10. Torales J, Halperin I, Hanzu F, et al.: Endoscopic endonasal surgery for pituitary tumors. Results in a series of 121 patients operated at the same center and by the same neurosurgeon. Endocrinol Nutr. 2014, 61:410-6. 10.1016/j.endoen.2014.07.002
  11. Zubair A, M Das J: Transsphenoidal hypophysectomy. StatPearls [Internet]. StatPearls Publishing, Treasure Island (FL); 2023.
  12. Pan X, Ma Y, Fang M, Jiang J, Shen J, Zhan R: Improvement in the quality of early postoperative course after endoscopic transsphenoidal pituitary surgery: description of surgical technique and outcome. Front Neurol. 2020, 11:527323. 10.3389/fneur.2020.527323
  13. Aiyer RG, Upreti G: Endoscopic endo-nasal trans-sphenoidal approach for pituitary adenomas: a prospective study. Indian J Otolaryngol Head Neck Surg. 2020, 72:36-43. 10.1007/s12070-019-01725-8
  14. Oertel J, Gaab MR, Linsler S: The endoscopic endonasal transsphenoidal approach to sellar lesions allows a high radicality: the benefit of angled optics. Clin Neurol Neurosurg. 2016, 146:29-34. 10.1016/j.clineuro.2016.04.016
  15. Hanson M, Li H, Geer E, Karimi S, Tabar V, Cohen MA: Perioperative management of endoscopic transsphenoidal pituitary surgery. World J Otorhinolaryngol Head Neck Surg. 2020, 6:84-93. 10.1016/j.wjorl.2020.01.005
  16. Qiao N: Endocrine outcomes of endoscopic versus transcranial resection of craniopharyngiomas: a system review and meta-analysis. Clin Neurol Neurosurg. 2018, 169:107-15. 10.1016/j.clineuro.2018.04.009
  17. Nie D, Fang Q, Wong W, Gui S, Zhao P, Li C, Zhang Y: The effect of endoscopic transsphenoidal somatotroph tumors resection on pituitary hormones: systematic review and meta-analysis. World J Surg Oncol. 2023, 21:71. 10.1186/s12957-023-02958-2
  18. Butenschoen VM, Schwendinger N, von Werder A, Bette S, Wienke M, Meyer B, Gempt J: Visual acuity and its postoperative outcome after transsphenoidal adenoma resection. Neurosurg Rev. 2021, 44:2245-51. 10.1007/s10143-020-01408-x

From https://www.cureus.com/articles/213241-navigating-the-surgical-landscape-a-comprehensive-analysis-of-endoscopic-vs-microscopic-transsphenoidal-pituitary-surgery-outcomes#!/

Long-term Outcomes and Complications from Endoscopic Versus Microscopic Transsphenoidal Surgery for Cushing’s Disease – a 15-year Single-center Study

Abstract

Background

Endoscopic endonasal surgery is the main transsphenoidal approach for pituitary surgery in many centers, however few studies compare the endoscopic and microscopic surgical approach with regard to long-term follow-up. This single-center study aimed to compare the two techniques over 15 years.

Methods

Medical records and magnetic resonance images from 40 patients with primary transsphenoidal surgery for Cushing’s disease at Sahlgrenska University Hospital between 2003 and 2018 were reviewed. Fourteen patients who underwent microscopic surgery and 26 patients who underwent endoscopic surgery were included in this study.

Results

In the microscopic group, 12 of 14 patients achieved endocrine remission, compared to 19 of 26 patients in the endoscopic group (n. s.). Three patients in each group developed a late recurrence. Complications were seen in 5 patients in the microscopic group and in 8 patients in the endoscopic group (n. s.). No serious complications, such as carotid artery damage, cerebrovascular fluid leakage, epistaxis, or meningitis, occurred in any group. The postoperative hospital stay was shorter in the endoscopic than the microscopic group.

Conclusion

Endoscopic endonasal surgery for Cushing’s disease showed no difference in remission, recurrence, and complication rates compared to the microscopic approach. The endoscopic group had a shorter postoperative hospital stay than the microscopic group, which in part may be due to the minimal invasiveness of the endoscopic approach.

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Conflicts of interest

The authors have no conflicts of interest.

Author statements

Conceptualization: D. Farahmand, E. Backlund, O. Ragnarsson and P. Trimpou

Data curation: Dan Farahmand, Erica Backlund, J. Carlqvist, T. Skoglund, T. Hallén, O. Ragnarsson, P. Trimpou.

Formal Analysis: D. Farahmand, E. Backlund

Funding acquisition: D. Farahmand

Investigation: D. Farahmand, E. Backlund, O. Ragnarsson and P. Trimpou

Methodology: D. Farahmand, E. Backlund, O. Ragnarsson and P. Trimpou

Project administration: D. Farahmand, E. Backlund, O. Ragnarsson and P. Trimpou

Supervision: D. Farahmand

Writing – original draft: Penelope Trimpou

Writing – review & editing: E. Backlund, O. Ragnarsson, T. Skoglund, T. Hallén, G. Gudnadottir, J. Carlqvist and D. Farahmand.

View full text

From https://www.sciencedirect.com/science/article/abs/pii/S1878875022009640

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

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

3D-Printing Technology Improves Outcomes In Pituitary Adenoma Surgery

Huang X, et al. Pituitary. 2019;doi:10.1007/s11102-018-0927-x.

March 3, 2019

The use of 3D-printed models could lead to less operation time and blood loss and fewer postoperative complications in adults who undergo endoscopic endonasal transsphenoidal surgery for pituitary adenomas and other conditions, according to findings published in Pituitary.

“Several factors influence the outcome of endoscopic endonasal surgery, including the tumor volume, patient age, lesion location and sphenoid pneumatolysis,” Xiaobing Jiang, of the department of neurosurgery at Union Hospital of Tongji Medical College of Huazhong University of Science and Technology in Wuhan, Hubei, China, and colleagues wrote. “An accurate model of the target tumor structure is a major prerequisite for a successful [pituitary adenoma] resection, especially for macroadenomas, as this may avoid disastrous complications due to suboptimal treatment.”

Jiang and colleagues conducted a retrospective analysis of 20 adults who underwent endoscopic endonasal transsphenoidal surgery at Union Hospital in Wuhan. Participants were included based on similar tumor sizes, the presence of no other diseases and nonintuitive tumor identification. All surgeries in the cohort occurred between January and August 2017, with 10 participants (mean age, 44.4 years; 50% women) receiving CT and MRI before surgery; the remaining 10 also received an operation with 3D printing (mean age, 41.2 years; 50% women).

To create the 3D models, images from CT and MRIs were combined. The 3D printer then used this information to create the model, which took between 2 hours, 10 minutes, and 4 hours, 32 minutes, to design and 10 hours, 12 minutes, and 22 hours, 34 minutes, to print.

After surgery, the researchers found that mean operation time was lower in participants who had 3D models compared with participants who did not (127 minutes vs. 143.4 minutes; P = .007). In addition, there was less blood loss in participants with 3D printing compared with participants without (159.9 mL vs. 170 mL; P = .009). The researchers noted that there were postoperative complications in 20% of the 3D-printing group and 40% of the CT and MRI alone group.

“As it is highly precise and allows personalization, 3D-printing technology has started to be applied in medicine in recent years. In neurosurgery, 3D-printing technology can provide models for the patients’ disease characteristics, such as skull defects, brain tumors, intracranial aneurysms and intracranial vascular malformations,” the researchers wrote. “We believe that with its continuous development, 3D-printing technology will be applied in clinical practice in the near future.” – by Phil Neuffer

DisclosuresThe authors report no relevant financial disclosures.

From https://www.healio.com/endocrinology/neuroendocrinology/news/online/%7B582c6512-708a-4900-ad20-f0adb5a79390%7D/3d-printing-technology-improves-outcomes-in-pituitary-adenoma-surgery