Complete regression of papillary tumor of the pineal region after radiation therapy: case report and review of the literature.

Papillary tumor of the pineal region (PTPR) is a rare neuroepithelial tumor that arises in the pineal region. The optimal treatment for PTPR remains controversial, as no definitive treatment strategy exists for this lesion. It is not clear whether aggressive surgical removal is superior to biopsy followed by radiotherapy. The majority of cases in the literature have undergone attempted gross total resection with a supracerebellar-infratentorial or a transcallosal-transventricular approach. In this report, we describe a case of PTPR in a 23 year-old male that presented as a third ventricular mass causing obstructive hydrocephalus. An endoscopic third ventriculostomy was performed followed by an endoscopic biopsy. Postoperative radiotherapy resulted in complete regression of the tumor with no evidence of tumor recurrence at 25 months. This case highlights a minimally invasive strategy for a rare neoplasm that resulted in a favorable response to radiation therapy, thereby avoiding the risks of aggressive surgical removal. We also review the radiographic and histopathologic features of PTPR and discuss various options of treatment reported in the literature.