Ectopic Breast Cancer in the Axilla after Bilateral Breast Cancer Surgery

Abstract

Abstract Background Ectopic breast cancer (EBC) is a rare disease, and cases of its occurrence in the axilla following surgery for bilateral breast cancer have not been previously reported. Case Presentation: We report the case of a 69-year-old woman who developed EBC cancer in the left axilla as a third metachronous primary cancer after bilateral breast cancer. Conclusion When a mass is observed in the axilla after breast cancer surgery, it is crucial to consider not only the possibility of lymph node metastasis but also the differential diagnosis of axillary EBC for appropriate diagnosis and treatment. If the mass is located just beneath the skin and on the outer side of the axilla, suspicion of EBC is warranted. As they do with pectoral breast cancer, the ultrasound findings of EBC vary according to the tissue structure.