[A case of partial response in liver metastatic lesion from gastric endocrine cell carcinoma treated with TS-1]

Endocrine cell carcinoma (ECC) of the stomach is a rare pathological type with a poor outcome. Standard chemotherapy has not yet been established. We experienced a case of partial response in the liver metastasis from the gastric ECC treated with TS-1. The patient was a 68-year-old female. An upper GI series and gastroendoscopy revealed pyrolus stenosis and CT-scan showed liver metastasis. A non-curative total gastrectomy was performed to allow oral intake. Since the histopathological examination revealed that tumor cells were partially positive for chromogranin A on immunohistochemical study, we diagnosed tumor ECC of the stomach. The patient with liver metastasis was treated using TS-1, and CT-scan showed a remarkable decrease (PR) in the metastatic lesion. TS-1 administration can improve the clinical outcome for ECC of the stomach.