[Renal cell carcinoma metastasizing to choroid plexus of lateral ventricle; a case report].

A rare case of renal cell carcinoma metastasizing to the choroid plexus of the lateral ventricle is reported. A 59-year-old woman was admitted to our institution on November 26, 1987 complaining of left-half headache for one month. She had a past history of right nephrectomy due to renal cell carcinoma 4 years before admission, and of right radical mastectomy due to breast cancer 10 years before admission. She had no abnormal neurological findings and laboratory results were normal. CT scan revealed a well-circumscribed, apparently homogeneously enhancing mass in the left lateral ventricle with mild ventricular dilatation. Left vertebral angiogram showed a tumor stain fed by the left posterior choroidal artery. The most likely diagnosis was thought to be metastasis of renal cell carcinoma. The patient underwent the operation for tumor removal via the posterior interhemispheric transcallosal approach 14 days after admission. A histological examination of the tumor determined the diagnosis of clear-cell type renal cell carcinoma. The operation was uneventful and the patient was discharged 20 days after operation without neurological deficit. But she had recent-memory disturbance, low activity, and gait disturbance in May 1989. CT scan revealed ventricular dilatation and tumor recurrence at the same site. She also suffered from diabetes due to the regrowth and invasion of primary tumor to the pancreas. She was discharged free of neurological defects after ventriculo-peritoneal shunt. In December 1989, she gradually deteriorated due to the regrowth of the intraventricular metastatic lesion, and now she is bedridden. Choroid plexus metastasis is quite rare, and, to our knowledge, only three cases have been described.