Leptomeningeal carcinomatosis originating from advanced gastric cancer--a report of three cases and review of the literatures.

Background: Leptomeningeal carcinomatosis (LMC) is a rare complication of gastric cancer. Case 1. A 57-year-old female was diagnosed with gastric cancer and underwent distal gastrectomy with D2 lymph node dissection. Two years later, the patient suffered from para-aortic lymph node metastases and provided chemotherapy. During the chemotherapy, the patient emergently visited our hospital with chief complaints of a severe headache and dizziness. The above symptoms promptly abated by meningeal drainage, with a high value of the cerebrospinal fluid (CSF) pressure. Despite the administration of subsequent chemotherapy, the patient's clinical state rapidly worsened, including gradual progression of both blindness and hearing loss. Case 2. A 42-year-old male was diagnosed with Stage IV gastric cancer due to both distant lymph node metastases and an ascites. Chemotherapy with S-1 plus docetaxel was initiated. Upon finishing the fifth course of treatment, the patient complained of a severe headache. The magnetic resonance imaging (MRI) findings were suggestive of LMC. Under suspicion of carcinomatous meningitis, the patient underwent both cerebrospinal drainage with a high pressure value of 180 mmH2O and a cytological examination with a diagnosis of Class V. Immediately following the cerebrospinal drainage, the patient's symptoms promptly diminished. Case 3. A 66-year-old female was diagnosed with gastric cancer and underwent total gastrectomy with D2 dissection. About a year later, the patient suffered from the peritoneal dissemination, and provided serial chemotherapy regimens for 13 months. Thereafter the patient suffered from mildly stiff shoulders followed by serial severe headaches, and meningeal drainage was performed. The CSF showed pleocytosis and the presence of neoplastic cells, leading a diagnosis of LMC. After the placement of an Ommaya reservoir, the intrathecal chemotherapy was performed. Within two weeks of treatment, the patient's condition improved significantly, and the cell counts in the CSF obtained from the Ommaya reservoir remained low for six months after the first diagnosis of LMC.

Conclusions: Although gastric LMC-affected patients often exhibit a fatal clinical course, the administration of intrathecal chemotherapy may improve survival. Systemic chemotherapy may be also administered in a limited number of patients with a superior performance status. At present, each case requires the individual making treatment decisions. Further accumulation of clinical cases and improving the overall understanding of the pathogenesis of this disease is needed in order to advance in the treatment of gastric LMC.