Operative Nuances of Capsular Dissection Techniques and Capsule Morphology in Pituitary Adenomas: Past 1-Year Case Experiences of a Tertiary Center.

BACKGROUND AND OBJECTIVES: The widespread use of endoscope and increased surgical experiences in pituitary adenomas (PAs) has raised the expectations for higher resection and cure rates. The subject that will meet this expectation in all types of adenomas is the capsule and its dissection. The purpose of this study was to go beyond the commonly mentioned pseudocapsule definition for small-sized adenomas in previous studies and to describe the capsule structure in different morphologies present in pituitary adenomas of all sizes. This includes detailing the nuances of capsular dissection (CD) and presenting postoperative surgical outcomes through the experiences of a high-volume tertiary center. METHODS: In our center, 534 patients underwent endoscopic trans-sphenoidal surgery because of pituitary adenoma in 2022 by the same surgeon. The data of the patients were examined retrospectively. The surgical techniques applied were grouped as adenoma resection only, capsular resection after internal debulking, and direct extracapsular resection. RESULTS: CD was performed in 275 (51.5%) patients. The gross total resection (GTR) rate in nonsecretory adenomas with and without CD was 90.7% (97/107) and 90.7% (97/107), respectively. The remission rate in secretory adenomas with and without CD was 81.0% (136/168) and 44.0% (67/152), respectively. When the patients were examined in 2 groups as those who underwent CD and those who did not, the application of CD had a positive predictive value in terms of GTR/remission (P: .036). Capsule thickness was not found to be statistically significant depending on tumor subtype, size, and aggressiveness, but capsule thickness was statistically significant in terms of total capsular resection (P: .045). CONCLUSION: The morphology of the capsule, tumor size/subtype/consistency, and patient-specific factors are crucial for the selection of the surgical technique to be applied. It is possible to increase the GTR/remission rates in adenomas of all sizes by capsule dissection. Moreover, performing CD does not contribute significantly to the development of potential complications in such cases.

Endoscopic transnasal surgery in optic pathway gliomas located in the chiasma-hypothalamic region: case series of ten patients in a single-center experience and endoscopic literature review.

OBJECTIVE: Optic pathway gliomas (OPGs) constitute approximately 3-5% of childhood intracranial tumors. In this study, the authors presented their experience of using the endoscopic endonasal approach to treat patients with OPG located in the chiasma-hypothalamic region and aimed to use the infrachiasmatic corridor in the endoscopic endonasal approach as an alternative to the transcranial approach in the surgical necessity of OPGs. METHODS: We retrospectively analyzed the data of ten patients diagnosed with OPG histopathologically among 3757 cases who underwent endoscopic endonasal surgery between August 1997 and March 2021 at Kocaeli University Faculty of Medicine Pituitary Research Center and Department of Neurosurgery. Mean follow-up period 48.5 months. During the postoperative follow-up period, 3 of these 10 patients underwent reoperation due to tumor recurrence. Combined (endoscopic endonasal approach + transcranial approach) approach was applied to 2 patients in the same session. Surgical and clinical outcomes were evaluated in detail. RESULTS: Ten patients with a mean patient age of 20.6 ± 11.4 were included in this study. The most common complaint was visual impairment. After surgery, improvement in visual impairment was observed in five patients. No increase in postoperative visual impairment was observed in any of the patients. Postoperative panhypopituitarism was not observed in any of the patients. STR resection was performed in 5 patients and NTR resection in 5 patients. No additional treatment was required during follow-up in 4 of 5 patients who underwent NTR. A total of 6 patients received postoperative radiotherapy treatment. CONCLUSIONS: In gliomas located in the chiasma-hypothalamic region, appropriate patient selection and endoscopic endonasal surgical treatment may contribute to the elimination of symptoms due to the mass effect of the tumor. It may also contribute to keeping the disease under control with targeted adjuvant therapies by clarifying the pathological diagnosis of the lesion.

The Endoscopic Endonasal Transsphenoidal Approach for Thyrotropin-Secreting Pituitary Adenomas: Single-Center Experience and Clinical Outcomes of 49 Patients.

OBJECTIVE: To analyze surgical outcomes and tumor characteristics of 49 patients with thyrotropin-secreting pituitary adenoma, a rare functional pituitary adenoma subtype with challenging surgery, who underwent endoscopic endonasal transsphenoidal surgery. METHODS: In this single-center study, clinical, radiological, surgical, and endocrinological data of 49 patients diagnosed with thyrotropin-secreting pituitary adenoma were retrospectively reviewed. RESULTS: Mean tumor size was 21.12 mm (6 microadenomas, 41 macroadenomas, 2 giant adenomas). Cavernous sinus invasion was present in 12 (24.48%) patients. Tumor consistency was firm in 23 (46.93%) patients. Plurihormonal secretion characteristics were present in 9 patients (5 growth hormone + thyrotropin and 4 growth hormone + prolactin + thyrotropin). Mean follow-up duration was 51.73 months. Of the cases with firm tumors, 14 patients had a history of antithyroid drug use; there was no statistically significant correlation between the antithyroid medication and the firmness of the tumor. Gross total resection was achieved in 32 (65.30%) cases, near-total resection was achieved in 14 (28.57%) cases, and subtotal resection was achieved in 3 (6.12%) cases. The analysis showed that the negative effect of >2 cm tumor size and cavernous sinus invasion on resection rate was statistically significant (P < 0.001). Although early remission was achieved in 33 (67.34%) patients, 44 (89.79%) patients were in euthyroid state at >3 months' follow-up. Complications were 4 new-onset pituitary deficiencies, 3 cases of permanent diabetes insipidus, 1 thyrotoxic crisis, and 1 cerebrospinal fluid leak. CONCLUSIONS: Endoscopic endonasal transsphenoidal surgery is the first-line treatment in thyrotropin-secreting pituitary adenoma and should be performed in a tertiary center. Gross total resection is the goal, and early diagnosis is essential for surgical success.

Endoscopic approach for giant pituitary adenoma: clinical outcomes of 205 patients and comparison of two proposed classification systems for preoperative prediction of extent of resection.

OBJECTIVE: Giant pituitary adenoma is considered a challenging pathology for surgery owing to its complications and low resection rate. In this study, the authors present their experience of using the endoscopic endonasal approach to treat patients with giant pituitary adenoma, and they aimed to develop a classification system for prediction of extent of resection. METHODS: The institutional medical records of patients diagnosed with giant pituitary adenoma who underwent endoscopic endonasal transsphenoidal surgery between August 1997 and December 2019 were retrospectively reviewed. Surgical and clinical outcomes were evaluated in detail. The effects of tumor characteristics on extent of resection were analyzed. The findings were used to develop two classification systems that could preoperatively predict extent of resection. Morphological score was based on tumor characteristics, and landmark-based classification was defined according to surgical zones based on neurovascular landmarks. The effects of change in surgical strategy, which aimed to maximize tumor resection and capsule dissection, on rates of resection and complications were evaluated before and after 2017. RESULTS: This study included 205 patients, with a mean patient age of 46.95 years and mean preoperative tumor diameter of 46.56 mm. Gross-total resection (GTR) was achieved in 35.12% of patients, near-total resection (NTR) in 39.51%, and subtotal resection (STR) in 25.36%. Extent of resection differed significantly between the grades and zones of the classification systems (p < 0.001 for both). Among patients with grade 3 tumor, 75.75% of patients achieved STR, 21.21% achieved NTR, and 3.03% achieved GTR. Among patients with zone 3 tumor, 65.75% achieved STR, 32.87% achieved NTR, and 1.36% achieved GTR. Both grade 3 and zone 3 indicated limited extent of resection. The mean (range) follow-up duration was 50.16 (9-247) months. Postoperative recovery of at least one hormone axis was seen in 15.24% of patients with pituitary deficiency, and development of new hormonal deficiency was observed in 22.43% of patients. Complications included permanent diabetes insipidus (7.80%), cerebrospinal fluid leakage (3.90%), postoperative apoplexy (3.90%), meningitis (3.41%), and epistaxis (3.41%). The surgical mortality rate was 1.46%. Among 85 patients treated before 2017, 27.05% of patients achieved GTR, 37.64% achieved NTR, and 35.29% achieved STR; among 120 patients treated after 2017, 40.83% achieved GTR, 40.83% achieved NTR, and 18.33% achieved STR. Seven patients in the pre-2017 cohort had postoperative apoplexy versus only 1 patient in the post-2017 cohort. There were no statistically significant differences between the two periods in terms of the incidence rates of other complications. CONCLUSIONS: Capsule dissection and GTR are valuable for preventing serious complications and reducing recurrence of giant adenoma. Treatment of giant pituitary adenoma may be better managed with the help of a classification system that provides information about extent of resection that can be achieved with an endoscopic approach.