Advanced gastric carcinoma combined with extra-adrenal pheochromocytoma resected after three courses of S-1 and cisplatin as neoadjuvant chemotherapy: report of a case.

We herein describe the case of a patient with advanced gastric carcinoma combined with extra-adrenal pheochromocytoma who received a radical operation after undergoing neoadjuvant chemotherapy. A 48-year-old woman was referred to our hospital for gastric carcinoma. Computed tomography revealed an enlargement of the regional lymph nodes and a para-aortic lymph node. A diagnosis of advanced gastric carcinoma was made (cT3, cN3, cM0, cStage IV according to the Japanese Classification of Gastric Carcinoma, 2nd English edition). A reduction in size was observed in both the gastric tumor and the lymph nodes around the stomach after neoadjuvant chemotherapy. However, the paraaortic lymph node showed no remarkable change. We thus suspected this para-aortic tumor not to be a lymph node, but instead to be an extra-adrenal pheochromocytoma, because of the different response from the other regional lymph nodes. An endocrinological examination confirmed the diagnosis of extra-adrenal pheochromocytoma. A gastrectomy and a resection of the pheochromocytoma were thus performed.