Intrasellar pilocytic astrocytomas: clinical, imaging, pathological, and surgical findings

A pilocytic astrocytoma is not usually considered in the differential diagnosis of an intrasellar tumor. An awareness of this tumor as primarily an intrasellar entity is important to avoid confusion during its diagnosis. We retrospectively examined the records of 631 patients treated at our institution between 2006 and 2010 who underwent transsphenoidal resection of pituitary tumors and identified those diagnosed with pilocytic astrocytoma. We excluded patients who harbored a pituicytoma. We also searched the literature for patients with a histologically confirmed diagnosis of intrasellar pilocytic astrocytoma. Only two patients in our series harbored intrasellar tumors and had a histologic diagnosis of pilocytic astrocytoma. We also found two other cases in the literature that met our criteria. Pilocytic astrocytoma should be considered in the differential diagnosis of an intrasellar lesion. An understanding of this tumor's radiological features can avoid diagnostic confusion.