In planning treatment of a gastric neoplasm in a patient previously treated for lobular breast carcinoma, it is important to differentiate a primary gastrointestinal tract tumor from a metastatic form. We report a case of a breast lobular carcinoma metastatic to the stomach. The patient underwent a subtotal gastrectomy for symptomatic disease. Although gastric symptoms appeared 14 years after the breast carcinoma, immunohistochemical analysis of the surgical specimen helped to establish that the gastric lesion, thought to be primary, was effectively a metastatic repetition of the breast neoplasm. To better define treatment in a gastric neoplasm patient previously treated for breast carcinoma, the preoperative diagnosis should rule out a metastatic disease. The patient described received an adjuvant chemotherapy according to breast cancer protocol after gastric resection for symptomatic disease. The patient is still alive and undergoing chemotherapy for peritoneal carcinosis.