Outcomes following resection of giant pituitary adenoma: a single-center retrospective analysis of 38 patients

Introduction: Giant pituitary adenomas (GPAs) only comprise ~5% of all pituitary tumors. Surgical management can be challenging given their proximity to and/or involvement with critical neurovascular structures. Various surgical approaches exist, but may vary in extent of resection and need for additional surgery. Understanding preoperative clinical characteristics, as well as surgical approaches, to maximize outcomes is an area of ongoing interest.

Methods: A retrospective analysis was conducted for all patients who underwent surgery for GPAs with either senior author (RWB, SM) between 2010 and 2023. GPA were defined as >=4cm in the long-axis, or with clear involvement in surrounding parenchyma and neurovascular structures causing mass effect. Patient data on demographics, pre-operative medication usage, surgical approach, complications, and outcome measures were collected.

Results: A total of 38 patients were included in this series (26 transsphenoidal/endoscopic endonasal resection [ESEN], 9 craniotomies [C] and 3 combination surgeries [ESEN+C]. Eight patients (21%) had prior surgeries. Average long-axis length was 4.6 +/- 1.2cm. Gross total resection (GTR) was achieved in 42% of patients. Complications included CSF leak (15.8%), post-operative hemorrhage (7.9%), hydrocephalus (18%) and subdural hygroma (2.6%). All episodes of hydrocephalus received an external ventricular drain (EVD), with 86% (6/7) requiring long-term CSF diversion. Nine (23.7%) patients were taken back to the operating room (OR) in an unplanned fashion for either post-operative hemorrhage and/or hydrocephalus (8) or worsening neurologic examination (1). The average LOS was 9.1, 22 and 25 days in the ESEN, C and ESEN+C groups, respectively. Disposition was primarily home except 3 ESEN (11.5%), 4 C (44.4%) and 2 ESEN+C (66.7%) patients who required rehabilitation.

Conclusion : Patients who undergo craniotomy as part of their surgical treatment are more likely to have a longer LOS and require rehabilitation or supportive care once discharged. Long-term CSF diversion was required for patients in all three surgical groups, though the majority were in patients undergoing craniotomy. Intervention type, as well as patient medical characteristics, likely play a role in surgical outcomes for GPAs.