A CASE OF MAMMARY GLAND METASTASIS OF STOMACH CANCER

In a 32-year-old female complaining of epigastralgia, a stomach cancer was found by radiography and endoscopy of the stomach. After admission, a mass was also noted in the mammary glands, and aspiration needle biopsy indicated a malignancy. Simultaneous double cancer of the stomach and mammary gland was suspected, and total gastrectomy was performed with modified radical mastectomy in an one-step approach. Postoperative histopathological examinations showed that both the gastric and mammary gland lesions were signet ring cell carcinomas, indicating mammary gland metastasis of stomach cancer. Metastatic mammary gland tumors are rare; to our knowledge, there have been reports of 80 cases, of which 16 including this case had metastases from stomach cancer. Differentiation of metastatic cancer from double cancer may be difficult when it is detected simultaneously with the primary lesion as in this case. However, the possibility of metastasis must be considered in the diangosis and treatment of multiple cancers.