Background: Adenoid cystic carcinoma of the breast is a rare neoplasm accounting for 0.1% of all malignant breast tumors and presenting most commonly as a painful breast mass. Compared with the more common histological forms of breast cancer, it has a more favorable prognosis and lymph node involvement or distant metastases seldom occur.
Case report: A unique case of multifocal adenoid cystic carcinoma of the breast presenting as a painful and well-defined lump and treated with conservative surgery with adjuvant radiotherapy is reported.
Conclusions: There is no consensus on the optimal management of this disease. A breast-conserving approach may be recommended even if mastectomy has been traditionally the treatment of choice. Chemotherapy, radiation, and hormonal therapy have been infrequently used and so far have had no defined role in this kind of neoplasm. The authors found no other reports in the literature focusing on a conservative approach to multifocal adenoid cystic carcinoma.