A Case of Stage I Adenoid Cystic Carcinoma of the Breast with Lung Metastasis Two and Half Years after Primary Surgery

Abstract

A 67-year-old woman was admitted to our department for abnormal breast cancer screening. After imaging tests and a core needle biopsy, she was diagnosed with left breast carcinoma, cT1bN0M0 Stage I, ER-, PgR-, HER2-, which was mostly suspected adenoid cystic carcinoma. Left breast conserving surgery and sentinel lymph node biopsy were performed. The histopathological diagnosis was adenoid cystic carcinoma (ER-, PgR-, HER2-, Ki-67 5%).

Although the tumor was triple negative breast cancer, her adjuvant therapy was only irradiation without chemotherapy because favorable prognosis appeared to be promised. After 2 and half years from the first surgery, a left lung nodule was noted by computed tomography. Thoracoscopic left upper lobectomy and lymph node dissection were performed to differentiate whether it was primary or metastatic, and the histopathological diagnosis was lung metastasis of adenoid cystic carcinoma.

In general, adjuvant chemotherapy is recommended for triple negative of other special types of breast cancer in accordance with normal invasive ductal carcinomas. On the other hand, adjuvant chemotherapy could often be omitted for breast adenoid cystic carcinoma, because the prognosis is good in many cases despite triple negative, provided that the axillary lymph node metastasis is negative. This paper deals with our experience with a case of postoperative lung metastasis of mammary adenoid cystic carcinoma without lymph node metastasis in the first operation.