Female Breast Cancer Health Center

Next to skin cancer, breast cancer is the most common type cancer that develops in women. Men also get breast cancer, although this is still extremely rare.

Cancer always starts in the cells, which make up the tissue that is found in the breast and throughout the body. Cells have a life of their own – they grow and mature and eventually die off, at which point they’re replaced.

Sometimes, though, something goes haywire – new cells might form even though the body doesn’t need them, and sometimes old or damaged cells don’t die off as they’re supposed to.

When this happens, cells start growing wild. All the extra cells build up and form a mass of some sort that’s called a lump, growth a tumor.
Tumors in the breast can be benign (not cancer) or malignant (cancer). 

Benign tumors are generally not harmful. Malignant or cancerous tumors, though, can invade nearby tissue and spread to the lymph nodes and other areas of the body. When cancer spreads, this is known as metastasis.

Men do develop breast cancer, and it’s very similar to the disease seen in women. It starts either in the ducts or the lobules, forms tumors and can spread from there. Male breast cancer is rare, accounting for only about one percent of all breast cancers diagnosed.

Review Date: 
March 22, 2012
Last Updated:
July 1, 2013