Breast
Rare breast cancers
Most breast cancers fall into a few common types, but a very small number — less than 1% — have unusual features under the microscope that look more like cancers that usually start in the salivary glands (the glands in your mouth that make saliva).
These rare breast cancers, such as adenoid cystic carcinoma (ACC), secretory carcinoma (SC) and mucoepidermoid carcinoma (MEC), tend to behave more like their salivary gland counterparts than typical breast cancers. This means they may grow differently, respond to treatment differently, and have a different long-term outlook.
Because of this, doctors sometimes look at how these cancers behave in the salivary glands to better understand and manage them when they appear in the breast.
ACC breast misdiagnosed as Triple Negative Breast Cancer (TNBC)
While ACC of the breast is slow-growing and treatable, it can be easily misdiagnosed as other forms of more aggressive breast cancer due to its status as a triple-negative breast cancer (TNBC). You can read about recent research presented at the San Antonio Breast Cancer Symposium (SABCS) 2024 by clicking the link below and, view the poster presented here.
Last updated August 2025