Outcomes of Aggressive Surgical Resection in Growth Hormone–Secreting Pituitary Adenomas with Cavernous Sinus Invasion

Background: Cavernous sinus (CS) invasion is an unfavorable factor hindering the remission of growth hormone (GH)-secreting pituitary adenomas. Little data exist on aggressive surgical resection, however. We investigated the role of CS exploration for GH-secreting pituitary adenomas with CS invasion. Methods: We classified 132 patients with GH-secreting pituitary adenomas invading CS into 4 groups. The patients underwent surgery using a microsurgical transsphenoidal approach (TSA) with endoscopic assistance. Adenomas with CS invasion confined to the medial compartment of the internal carotid artery (ICA) were classified as type A (without radiologic evidence) or type B (with radiologic evidence). Adenomas with ICA encasement were classified according to the surgical approach as type C (standard TSA) or type D (far-lateral TSA). Surgical and endocrinologic outcomes were compared across groups. Results: For type A, B, C, and D tumors, the rates of gross total resection were 100%, 73.6%, 14.7%, and 0%, respectively, and the rates of endocrinologic remission by surgery alone were 100%, 62.3%, 26.5%, and 0%, respectively. There was no endocrinologic remission by surgery alone for type D tumors; nevertheless, compared with type C tumors, type D tumors showed marked reductions in the postoperative nadir of GH at 1 week, 6 months, and 1 year and of insulin-like growth factor I at 1 year. Conclusions: For tumors with CS invasion confined to the medial compartment of the ICA, total resection should be attempted by direct visualization of the entire medial wall of the CS. Even for tumors with ICA encasement, aggressive tumor resection by far-lateral TSA can increase the chance of remission with the help of adjuvant treatment.