Breast cancer types: What your type means

Not all breast cancers are the same. Understand what type of breast cancer you have and how it differs from other types of breast cancer.

By Mayo Clinic Staff

Once you've been diagnosed with breast cancer, your doctor will review your pathology report and results of any imaging tests to understand the specifics of your tumor.


Here's what's used to determine your breast cancer type.

In what part of the breast did your cancer begin?




    Ductal carcinoma can remain within the ducts as a noninvasive cancer (ductal carcinoma in situ) or it can break out of the ducts (invasive ductal carcinoma).

  • Milk-producing lobules. Lobular carcinoma starts in the lobules of the breast, where breast milk is produced. When it breaks out of the lobules, it's considered invasive lobular carcinoma. The lobules are connected to the ducts, which carry breast milk to the nipple.

How do your cancer cells appear under a microscope?


  • Cancer cells with unique appearances. Some subtypes of breast cancer are named for the way they appear under the microscope. Subtypes include tubular, mucinous, medullary and papillary. Your subtype gives your doctor some clues about your prognosis and how your cells may respond to treatment.
Feb. 06, 2015 See more In-depth