From the archives of the AFIP: lesions of the pineal region: radiologic-pathologic correlation.

Lesions of the pineal region include a diverse group of entities. The most common neoplastic lesions are the germ cell tumors. Germ cell tumors may be hormonally active, and evaluation of serum or cerebrospinal fluid levels of oncoproteins assists in making the diagnosis. Neoplasms arising from the pineal parenchyma include the low-grade pineocytoma, pineal parenchymal tumor of intermediate differentiation, and the highly malignant pineoblastoma. Germ cell tumors and pineal parenchymal neoplasms do not have pathognomonic imaging findings, but imaging in combination with laboratory evaluation helps narrow the differential diagnosis. Neoplasms may also arise from the variety of cell types residing in the proximity of the pineal gland. These include lipomas, meningiomas, and astrocytomas. Congenital lesions such as epidermoid and dermoid cysts and lipomas can also occur. Knowledge of the variety of lesions that occur in the pineal region, their imaging appearances, and their clinical features assists in narrowing the radiologic differential diagnosis and optimizing patient treatment.