Breast Cancer

Breast Cancer

If you or a loved one has been diagnosed with breast cancer, it's important to understand some basics: What is breast cancer and how does it happen?

In this section, you can learn about how breast cancer develops, how many people get breast cancer, and what factors can increase risk for getting breast cancer.

Breast cancer general terms

It is important to understand some of the key words used to describe breast cancer.

Carcinoma

This is a term used to describe a cancer that begins in the lining layer (epithelial cells) of organs such as the breast. Nearly all breast cancers are carcinomas (either ductal carcinomas or lobular carcinomas).

Adenocarcinoma

The ducts and lobules of the breast are glandular tissue (they make breast milk), so cancers starting in these areas are sometimes called adenocarcinomas.

Carcinoma in situ

In breast cancer, in situ means that the cancer cells remain confined to ducts (ductal carcinoma in situ) or lobules (lobular carcinoma in situ). They have not invaded into deeper tissues in the breast or spread to other organs in the body, and are sometimes referred to as non-invasive breast cancers.

Invasive (infiltrating) carcinoma

Most breast cancers are invasive carcinomas -- either invasive ductal carcinoma or invasive lobular carcinoma.

Sarcomas are cancers that start from connective tissues such as muscle tissue, fat tissue, or blood vessels. Sarcomas of the breast are rare.

Types of breast cancers

There are several types of breast cancer, although some of them are quite rare. In a clinical setting, breast cancer is commonly diagnosed using a "triple test" of clinical breast examination (breast examination by a trained medical practitioner), mammography, and fine needle aspiration cytology. Together, these three tools can be used to diagnose breast cancer with a good degree of accuracy.

Other options for biopsy include core biopsy, where a section of the breast lump is removed, and an excisional biopsy, where the entire lump is removed.

Breast cancer is always caused by a genetic abnormality (a “mistake” in the genetic material). Initially, breast cancer may not cause any symptoms. In some cases, however, the first sign of breast cancer is a new lump or mass in the breast that you or your doctor can feel. A lump that is painless, hard, and has uneven edges is more likely to be cancer. But sometimes cancers can be tender, soft, and rounded. According to the American Cancer Society, any of the following unusual changes in the breast can be a symptom of breast cancer:

swelling of all or Stage of the breast Cancer

breast pain

redness, scaliness, or thickening of the nipple or breast skin

a nipple discharge other than breast milk