[Case of leptomeningeal carcinomatosis effectively treated with intrathecal chemotherapy using ventriculoperitoneal shunt].

A 70-year-old man presented with dizziness, headache and hearing loss. He was admitted to our hospital because of increasing unsteadiness of gait. Magnetic resonance imaging of the brain revealed meningeal thickening with enhancement. The lumbar puncture revealed high opening pressure. The cerebrospinal fluid showed pleocytosis, high carcinoembryonic antigen (CEA) concentration, and presence of neoplastic cells, leading to the diagnosis of leptomeningeal carcinomatosis. Systemic investigation for primary neoplasm identified a Bormman type 3 gastric cancer (papillary adenocarcinoma with micropapillary pattern). Except for the meninges, no metastatic lesions could be detected. A ventriculoperitoneal shunt (Codman Hakim Programmable Valve) was placed for management of intracranial hypertension and intrathecal chemotheray. He was started on oral S-1 (TS-1) combined with intrathecal methotrexate injection using the VP shunt reservoir. In two weeks, headache and hearing loss completely disappeared and gait disturbances started to improve. CSF findings also improved remarkably with disappearance of neoplastic cells and almost normalization of CEA. For the next five months, he was well on oral S-1 and monthly intrathecal chemotherapy, being able to walk using a walker and to stay at home. He subsequently developed posterior cortical symptoms such as prosopagnosia and cortical blindness and gradually lapsed into coma. He died from pneumonia one year after the onset of neurological symptoms. At autopsy, primary gastric cancer was found but much reduced in size. No peritoneal metastasis could be found. In the brain, leptomeningeal carcinomatosis involved the occipital lobes, the base of the temporal lobe, and the cerebellum. We suggest that intrathecal chemotherapy using ventriculoperitoneal shunt with programmable valve system could be an effective method for the treatment of meningeal carcinomatosis.