A Case of a Bulky Axillary Tumor which was Difficult to be Diagnosed as Ectopic Breast Cancer

Abstract

We present a case of a 51-year-old woman with a bulky tumor having ulceration on its surface with hemorrhage in her left axillary fossa. Palpation, mammography, ultrasonography and magnetic resonance imaging detected no tumor in her mammary gland. Primary axillary tumor was thus suspected. A punched biopsy showed poorly differentiated adenocarcinoma. The tumor excision was performed with dissection of its axillary lymph nodes. The immunohistochemistry was useful to diagnose it as breast cancer finally. Neither components of normal mammary gland nor structures of lymph node were present in the resected specimen, for that we had great difficulties in differentiating whether it was ectopic or occult breast cancer. Based on a review of the relevant literature, it would be reasonable to diagnose it as ectopic breast cancer rather than occult breast cancer because of the wide-spread ulceration on its surface having no metastasis to the adjacent lymph nodes in spite of its bulky mass more than 10 cm in maximum diameter. There were no tumor cells in the stump of the specimen or in the dissected lymph nodes. The patient has strictly been observed, while she is on postoperative medication with aromatase inhibitor (anastrozole) and oral tegaful/uracil (UFT).