Aggressive Pituitary Tumor with Crooke's Cells and Invasion of the Posterior Fossa.

Abstract

Pituitary adenomas are mostly benign in character and are managed via a transsphenoidal approach in most cases. Crooke's cell adenoma (CCA) is a particular variant accounting for less than 1% of the pituitary adenomas. They have a distinctive histopathologic pattern and behavior. We present a case of a 56-year-old man with recurrent pituitary adenoma and complicated neurosurgical history. Imaging follow-up showed a suprasellar mass with progressive growth into the posterior fossa. Surgical management via retrosigmoid craniectomy was performed, and histopathology elucidated Crooke's cells. CCA is recognized by its local aggressiveness and high recurrence rates. They tend to be locally invasive; however, posterior fossa invasion has not been reported to date. We aim to contribute to the arsenal of differential diagnosis of similar pituitary tumor cases.