Gastric tumor from metastasis of breast cancer.

Metastatic tumours of the stomach have been reported to result from various types of cancer. Among them, gastric metastasis from breast cancer has been recognised in 0.3-18% patients (1-4). Here, a rare case of metastatic gastric tumour derived from breast carcinoma is reported. Gastric endoscopy confirmed a large, friable mass (approximately 5 cm in diameter) in the upper part of the gastric body. The mass within the stomach was difficult to distinguish from primary gastric cancer, although biopsies of this lesion revealed the characteristics of adenocarcinoma. In addition, immunohistochemistry showed the positive expression of mammaglobin. Taken together, the evidence pointed to metastasis of breast cancer to the stomach. The patient was treated with hormonal therapy (letrozole), and the size of the metastasis in the stomach was markedly reduced. Therefore, a gastric metastasis from breast cancer was diagnosed successfully using immunohistochemistry and unnecessary surgery was avoided. In conclusion, although gastric metastatic tumours derived from breast carcinoma are rare, their accurate pre-operative diagnosis and appropriate systemic treatment is essential.