Frequent development of leptomeningeal carcinomatosis in patients with peritoneal dissemination of gastric cancer.

We detected 7 cases of leptomeningeal carcinomatosis in 126 patients with peritoneal dissemination of gastric cancer who received combined systemic and intraperitoneal chemotherapy. Leptomeningeal carcinomatosis was diagnosed 79-1540 days after the diagnosis of the primary gastric cancer. Patients presenting with various neurological symptoms were diagnosed by cerebrospinal fluid (CSF) cytology and radiological imaging. Irradiation to the whole brain and spine was performed in 4 patients, and provided palliation and increased survival for 1 patient. Intrathecal chemotherapy and drainage of CSF was performed in 1 patient each, but produced no significant clinical benefit in either of them. Survival after the diagnosis of leptomeningeal carcinomatosis was between 3 and 155 days. As patients with peritoneal dissemination of gastric cancer are living longer because of improved chemotherapy, clinicians must recognize the possibility of leptomeningeal carcinomatosis when patients complain of neurological symptoms.