Breast Adenoid Cystic Carcinoma: A Rare Case Report and Review of the Literature.

Background: Primary adenoid cystic carcinoma (ACC) of the breast is a rare subtype of invasive breast cancer. It has a particular interest because of its excellent prognosis conversely to other triple-negative breast cancers that are associated with poor prognosis. The place of chemotherapy and radiotherapy remains controversial and there is no consensus on optimal management of the ACC of the breast.

Case Report: A 50-year-old woman, presented with a palpable right breast lump. Core biopsy of the lump revealed an adenoid cystic carcinoma. A lumpectomy with axillary lymph node dissection was performed and completed by a mastectomy because of the positive surgical margins. The histopathological examination revealed an adenoid cystic carcinoma, with negative expression of hormone receptors and human epidermal growth factor receptor 2 HER2 and with no lymph node involvement. The patient underwent adjuvant sequential chemotherapy with anthracycline and taxane followed by radiotherapy. We discuss diagnosis, prognostic, and treatment options for ACC of the breast in light of existing literature.

Conclusion: Adenoid cystic carcinoma of the breast is a rare variant of triple negative breast cancer with excellent prognosis. Surgical treatment is the mainstay with no clear consensus for radiotherapy and chemotherapy.