Treatment Patterns and Clinical Outcomes of Adenoid Cystic Breast Carcinoma: A Single-Institution Experience.

Abstract

Adenoid cystic breast carcinoma (ACC) is a rare subtype of triple-negative breast cancer. We aim to characterize the treatment patterns and clinical outcomes of women diagnosed with ACC at a large medical center. Female patients diagnosed with ACC at our institution between 2009 and 2019 were retrospectively identified. Patients with limited clinicopathologic data were excluded. In our final study cohort (n = 9), the majority of ACCs (6/9, 66.7%) were hormone receptor (-) (HR-) and HER-2/neu (-) (HER2-), while 3 ACCs were HR+ HER2-. Two patients received adjuvant chemotherapy, and 4 patients received adjuvant radiotherapy. The crude local and distant recurrence rate of our cohort was 22.2% and 11.1% (median follow-up of 36 months). The majority of ACCs were triple negative but some ACCs were HR+. The unadjusted local and distant recurrence rates were not negligible, suggesting that adjuvant chemotherapy and radiotherapy may be warranted in select cases.