Breast Cancer Proliferation Definition

Proliferation means “overgrowth,” and in this video Dr. Harness explains how proliferation relates to breast cancer as well as some of the causes of proliferation .

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Jay K. Harness, MD: Proliferation is a term meaning the overgrowth of something. So focusing on the cells lining the inside of the ducts or the lobules of the breast, the proliferation is the increased growth, the layering, increased layers of cell growth. We often don’t know what causes the proliferation. There are normal things that do that, for instance, in the four-week typical menstrual cycle, the last two weeks are called the proliferative phase. Progesterone is proliferating and thickening the lining of the cells of the ductal system in preparation for potential pregnancy.

Abnormal things or an abnormal stimulus will cause the proliferation of the cells of the ducts, and if that proliferation then goes on, it could eventually lead to cancer. Again, we don’t know the cause of breast cancer or the cause of that kind of proliferation, but the term ‘proliferation’ means the overgrowth; sometimes normal, sometimes abnormal.

Dr. Jay K. Harness is a board certified surgeon currently treating patients at St. Joseph Hospital in Orange, CA. Dr. Harness specializes in complete breast health, breast cancer surgery, oncoplastic reconstruction, genetic screening, management of breast health issues, risk assessment and counseling. Dr. Harness is the medical director for Breast Cancer, and guides this first ever social media show’s information by drawing on his former leadership experience as the President of the American Society of Breast Surgeons and Breast Surgery International. Dr. Harness graduated from the University of Michigan, Ann Arbor in 1969 and spent time early on in his career at the University of Michigan Medical Center.


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