[Extraneural metastases of malignant brain tumors through ventriculoperitoneal shunt--report of two autopsy cases and a review of the literature (author's transl)].

Internal drainage of cerebrospinal fluid utilizing a mechanical tube has been an increasingly common and effective procedure for the relief of non-communicating hydrocephalus with intracranial tumor. However, several cases have recently been reported in which extraneural metastases of the tumor were initiated through the shunt tube implanted. The purpose of this paper is to present two cases with malignant brain tumor metastasizing extraneurally through ventriculoperitoneal shunt, and to review the reported cases in the literature. Case 1 The patient, a 9-year-old boy, had been suffering from headache and vomiting for 3 months prior to admission to the Neurosurgical Clinic, Gumma University Hospital. On admission, he had choked discs and cerebellar dysfunction with a staggering gait. The clinical diagnosis was a 4th ventricle tumor. On November 29, 1971, a suboccipital craniectomy was performed. A medullary tumor in the 4th ventricle was partially removed, and ventriculoperitoneal shunt was also performed. Subsequently postoperative irradiation was given, and the symptoms were abated. Histological diagnosis was ependymoblastoma. Thirteen months later, he was again admitted because of visual disturbance, psychic change and pituitary hypofunction. Bilateral frontal craniotomy revealed a large mass over the midline of the anterior skull base, accompanied by numerous meningeal neoplastic deposits. The tumor was partially removed and histologically proven to be meningeal metastases of ependymoblastoma. Irradiation was again given and the symptoms improved. But the 4th ventricle tumor recurred 5 months after the 2nd operation, and then a massive intraperitoneal effusion appeared. Cytological examination revealed clusters of tumor cells in the ascites. The patient died on September 8, 1974, namely 22 months after the ventriculoperitoneal shunt was implanted. Postmortem examination showed a solid tumor in the 4th ventricle which was accompanied by diffuse meningeal dissemination, and metastases were present throughout the peritoneal surface...