Revista de Oncología Integrativa

Carcinoma Originating from Aberrant Breast Tissue: Case Report and Review of the Literature

Abstract

L Boulaamane, B Khanouss, B El Ghissassi, H M rabti and H Errihani

Aberrant mammary tumors are ectopic tumors, which represent 0.3% of all breast cancers. These tumors often occur close to normal breast, near the sternum, epigastrum, subclavicular, and axillary area which is the most common. We report a 76-year-old woman, without history of disease, presenting one year ago, a nodule located between breasts, increasing rapidly in size. Clinical examination found an inflammatory mid-chest mass, measuring 15cm of diameter, located between breasts. Axillary lymph nodes were not enlarged, and no masses were palpable in the breasts. Biopsy with immuno-histochemical study showed invasive ductal breast origin carcinoma, with positive CK7 antigen, negative CK20 antigen, positive hormone receptors and negative HER2/neu oncoprotein. Bilateral mammography showed invasion the left breast. Computed tomography showed bilateral pulmonary metastasis. The patient received 5 courses of palliative chemotherapy based on Anthracycline, with more than 80% of partial response obtained. The patient died from sepsis before receiving the sixth course of treatment. Aberrant mammary tumors originated from accessory fragments of breast tissue beyond mammary gland. These aberrant breast tissues can grow and cancerize, with or without involvement of the two normal mammary glands. In this case report, both normal breasts are free from any adjacent tumor proliferation, and it is the first case in literature, reporting a considerable size of aberrant breast tissue.