Spindle cell oncocytoma: illustrative case

Abstract

BACKGROUND Spindle cell oncocytoma (SCO) is a rare, nonadenomatous sellar tumor that often mimics pituitary adenomas both radiographically and clinically, making diagnosis and treatment difficult. OBSERVATIONS A 67-year-old male presented with fatigue and weakness, with MRI revealing an enhancing sellar mass with suprasellar extension and laboratory findings consistent with panhypopituitarism. He underwent endoscopic endonasal resection, which revealed a fibrous, highly vascular tumor adherent to surrounding tissue, consistent with SCO on final pathological analysis. Gross-total resection (GTR) was achieved, and the patient has been monitored regularly with no signs of recurrence at 9 months postoperatively. LESSONS SCOs are an exceedingly rare entity often indistinguishable from pituitary adenomas preoperatively, yet their intraoperative hypervascularity and fibrous texture can complicate resection and predispose patients to recurrence. Accurate identification of these tumors and GTR when possible are essential to appropriate treatment. https://thejns.org/doi/10.3171/CASE26333