[Medulloblastoma originating in the pons].

Medulloblastoma usually originates in the cerebellum. We report here a case of medulloblastoma originating in the pons. Pontine medulloblastoma is extremely rare, with only one report in the literature. An 11-year-old girl was admitted to our hospital with vertigo. Magnetic resonance imaging (MRI) revealed a tumor originating in the pons. On the 4th day after admission, the tumor bled. Because the patient's life was in danger from brain herniation, hematoma removal and tumor resection were carried out. The diagnosis was medulloblastoma. After surgery, the patient received radiation therapy and chemotherapy. Unlike tumors originating in the cerebellum, this tumor did not seem to be effectively reduced by these therapies. Radiation therapy and chemotherapy may not be effective for medulloblastoma originating in the pons. We considered it necessary to make a histological diagnosis even though the tumor originated in the pons and resection was difficult technically.