Many of these cancers have imaging findings that, when understood, help Adenoid cystic carcinoma (AdCC) of the breast is rare, comprising. Apocrine breast cancer is a rare type of invasive ductal breast cancer. Apocrine tumors are often “triple negative”, meaning that the cells do not express the. Breast sarcomas are a very rare form of breast cancer, accounting for fewer than 1% of all breast cancers. Mucinous breast cancer, also called colloid breast cancer, is a rare type of invasive ductal breast cancer that accounts for less than 2% of all breast cancers. Breast Cancer Program We hope it will be reassuring to know that our team at the Center for Rare Breast Tumors is dedicated to latest research and treatment of. The Center for Rare Breast Tumors at Johns Hopkins Kimmel Cancer Center offers the National Cancer Institute -designated Comprehensive Cancer Centers. Metaplastic breast cancer is a rare form of breast cancer, accounting for fewer than 1% of all breast cancers. It differs from the more common kinds of breast.