Unusual presentation of adult metastatic peritoneal medulloblastoma associated with a ventriculoperitoneal shunt: a case study and review of the literature.

Patients with medulloblastoma uncommonly develop extracerebral metastases. We describe an adult patient with the unusual occurrence of intraperitoneal metastases associated with a ventriculoperitoneal (VP) shunt, as well as her subsequent treatment with high-dose chemotherapy and bone marrow transplantation. We review the literature regarding this rare presentation and association of metastatic spread via VP shunt devices. A 37-year-old woman presented with a rapidly enlarging pelvic mass. She had a history of medulloblastoma and had been treated with a combination of surgery, chemotherapy, and radiation 5 years previously, at which time a VP shunt had been placed for cerebrospinal fluid leakage. At laparotomy, she had unresectable intraperitoneal metastatic medulloblastoma. After an excellent response to cyclophosphamide, etoposide, and cisplatin, she underwent a resection of residual disease, followed by high-dose chemotherapy and a bone marrow transplant. We conclude that adult onset medulloblastoma with metastasis to the peritoneal cavity is rare and may be associated with a VP shunt.