Abstract
A 54-year-old woman was seen at the hospital because of a left axillary tumor. With an excision biopsy, lymph node metastasis of adenocarcinoma was diagnosed. First, metastasis from the mammary gland was suspected, but no abnormallities were found clinically in the bilateral breasts. Based on facts that immunological staining of the axillary metastatic lesion was positive for lactalbumin and no other origins were detected, occult breast cancer was most probable. A left pectoral muscle-preserving mastectomy (lt-Bt+Ax+Ic) was performed. The rescted mammary gland was histologically and minutely explored, but no malignant lesions were demonstrated. Thereafter when about 2 years has past, metastatic foci appeared in the left internal thoracic lymph node. As a result of radiation therapy and chemotherapy, the patient has been doing well as of 3 years after the operation.
It is thought that immunological staining of the lymph node can offer efficient information in the diagnosis of occult breast cancer.
