Swelled Lymph Nodes Don't Always Mean Breast Cancer

by Lillie Shockney, R.N., M.A.S.
I get a lot of emails, especially from teenage girls, asking if swelling in the lymph nodes under their arm means they have breast cancer. Not likely. There are lots of other, more common reasons for swelling in these important glands.

Lymph nodes play an important part in the body's defense against infection. The lymph fluid they produce travels throughout the body in the lymphatic system, which filters impurities from the body.

Lymph nodes may swell from infection, inflammatory conditions, an abscess, or cancer. By far, the most common cause of swollen lymph nodes is infection, most often associated with shaving the underarm a bit too closely and causing an infection in the hair follicle.

When swelling appears suddenly and is painful, it is usually caused by injury or an infection. Enlargement that comes on gradually and painlessly may, in some cases, signal that breast cancer may be present.

If you have swelling under your arm, notice whether it appears red and feels hot and tender to the touch. If that's the case, odds are in your favor that it is infection-related. If the swelling developed gradually and is not painful, then it's time to investigate. Either way, call your primary care physician so you can be properly evaluated.