CLINICAL STUDIES DIAGNOSIS AND MANAGEMENT OF PINEOCYTOMAS Vivek R. Deshmukh, M.D. Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, Arizona Kris A. Smith, M.D. Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, Arizona Harold L. Rekate, M.D. Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, Arizona Stephen Coons, M.D. Division of Neuropathology, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, Arizona Robert F. Spetzler, M.D. Division of Neurological Surgery, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, Arizona Reprint requests: Robert F. Spetzler, M.D., c/o Neuroscience Publications, Barrow Neurological Institute, 350 West Thomas Road, Phoenix, AZ 85013-4496. Email: neuropub@chw.edu Received, August 18, 2003. Accepted, March 24, 2004. OBJECTIVE: Pineocytomas are associated with the most favorable prognosis of all pineal tumors. However, a subset of pineocytomas may have a predilection for recurrence and therefore behave aggressively. PATIENTS AND METHODS: Records of nine patients (five men, four women; mean age, 44 yr; range, 24–63 yr) with histologically diagnosed pineocytomas consecutively treated between 1990 and 2003 were reviewed retrospectively to identify factors predictive of aggressiveness. Eight patients presented with hydrocephalus and four with tectal compression. Three patients underwent gross total resection, and six underwent subtotal resection or biopsy. RESULTS: Three local recurrences necessitated reoperation. One recurrence involved the obex of the fourth ventricle. The mean time to recurrence was 3.5 years (range, 1–7 yr). There was no correlation between histological features and tumor recurrence. Patients undergoing radiosurgery showed stable or attenuated local disease (mean follow-up, 19.3 mo; range, 6–36 mo). Mean radiographic follow-up was 34 months (range, 6 mo to 10 yr). Mean clinical follow-up was 36 months (range, 1 mo to 10 yr). CONCLUSION: A subset of pineocytomas demonstrates the potential for symptomatic recurrence. We advocate an attempt at gross total tumor resection for all symptomatic patients with tectal plate compression, reserving radiosurgery for small, subtotally resected, or recurrent lesions. Patients must be followed closely for recurrence. Ra- diosurgery seems to be beneficial for local tumor control. Further investigation is needed to identify histological markers for pineocytomas that behave aggressively. KEY WORDS: Pineocytoma, Radiosurgery, Recurrent tumor Neurosurgery 55:349-357, 2004 DOI: 10.1227/01.NEU.0000129479.70696.D2 www.neurosurgery-online.com P ineal region tumors are rare and account for 0.4 to 1% of intracranial tumors in Western countries and for 2.2 to 8% of intracranial tumors in northeastern Asian countries (4, 10, 15, 18, 30). Germinomas and pineal parenchymal tu- mors constitute the majority of pineal region tu- mors in adults (6, 24). After germinomas, pineal parenchymal tumors are the second most com- mon pineal tumors in adults and account for 15 to 30% of pineal region tumors. The designation of pineal parenchymal tumor includes pineocyto- mas, pineal parenchymal tumors of intermediate differentiation or mixed pineocytomas/ pineoblastomas, and pineoblastomas. Within this spectrum, pineocytomas are regarded as the most benign tumor. Pineocytomas tend to recapitulate the normal pineal gland (9, 15, 16, 33). The natural history of this disease is believed to be indolent, and treated patients typically have high 5- to 10- year survival rates (2, 10, 28, 32–34). Magnetic resonance imaging (MRI) findings such as enhancement, calcification, and well- defined margins are suggestive of a pineocy- toma but are by no means diagnostic (4, 8, 20, 31, 32, 36, 41). Therefore, tissue diagnosis is imper- ative. The recommended treatment for pineocy- tomas ranges from stereotactic/endoscopic bi- opsy to craniotomy and gross total resection (11, 23, 25). The role of adjuvant radiotherapy has not been clearly delineated. The rarity of these tumors makes a prospec- tive trial examining these issues extremely dif- ficult to formulate. We therefore reviewed our series of surgically treated pineocytomas to evaluate the efficacy of treatment, recurrence rate, utility of adjuvant radiotherapy, and fac- tors that might predict an aggressive course. METHODS We retrospectively reviewed the clinical, imaging, and operative findings and the his- tological features of pineocytomas in nine pa- tients (five men, four women) consecutively NEUROSURGERY VOLUME 55 | NUMBER 2 | AUGUST 2004 | 349