Treatment of Giant Pituitary Adenomas in the Era of Endoscopic Transsphenoidal Surgery: Strategy, Outcome, and Complications

Introduction: As giant pituitary adenomas (GPAs) of ≥4 cm diameter frequently extend into multiple anatomical compartments, encase neurovascular structures and exhibit invasive growth pattern, management is challenging and often combines multiple transsphenoidal, transcranial and radiation treatments. The aim of this study was to describe the treatment strategy, outcome and complications of a large consecutive multicenter series of GPAs in the era of endoscopic transsphenoidal surgery (ETS).

Methods: Retrospective case–control series of 64 patients (mean age: 50.6 years, 22–84 years) with GPAs (mean maximal tumor diameter: 47 mm, 40–74 mm) surgically treated at two tertiary care centers experienced in ETS.

Results: Primary surgery was endoscopic in all 64 GPAs (ETS in 66%, extended ETS in 34%). Surgical results were stratified in group A (gross total or partial resection with intracavernous remnant, 33%) and group B (PR with intracranial remnant, 67%). Growth pattern was most commonly round shape (79%) in group A and multilobular in group B (89%). Only in group B, early transcranial reoperation was required due to hemorrhagic remnant transformation (14%). In group A, no patient required second surgery, 9% were treated with radiosurgery. In group B, 7% required second ETS for descending adenoma remnant, 12% transcranial surgery, 21% extended ETS. There was no mortality in this series. Severe complications included stroke (6%), meningitis (6%), hydrocephalus requiring CSF diversion (6%), and visual deterioration (3%). Postoperative cerebrospinal fluid leak (14%), diabetes insipidus (transient 16%, permanent 6%), hypopituitarism (17%). At follow-up (3 years, 0.5–16 years), stable disease was achieved in 91% of cases.

Conclusion: Endoscopic transsphenoidal surgery is an effective primary treatment modality for GPAs. After incomplete resection, we recommend postoperative imaging and early reoperation in cases of enlarging remnant by hemorrhagic transformation. Due to the high rate of invasive growth into surrounding structures an individual multimodality treatment plan may include multiple reoperations, medical therapy, radiosurgery and eventually chemotherapy.

Publication History

Article published online:
12 February 2021