Important Facts About Breast Cancer Tumors

Woman pointing to area on mammogram x-ray, close-up
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A cancerous tumor in the breast is a mass of breast tissue that is growing in an abnormal, uncontrolled way. The tumor may invade surrounding tissue, or shed cells into the bloodstream or lymph system.

What They Feel Like

A breast tumor is very hard, like a bit of raw carrot. It will have an irregular shape and feel bumpy (not smooth). It may not be moveable during a breast self-exam, but since tissue around it may move, it’s sometimes hard to know if the lump is moving, or if healthy tissue around it is moving.

How They Appear on Mammograms

A breast tumor is a dense mass and will appear whiter than any tissue around it. Benign masses usually are round or oval in shape, but a tumor may be partially round, with a spiked or irregular outline as part of its circumference. If a mass has a multi-pointed star-shaped outline, it is described as spiculated. Keep in mind that to the untrained eye, other masses may appear like tumors, but are not. Only a trained radiologist should make the call.

What Happens If You Have a Tumor

If your mammogram shows a very dense mass which appears to be a tumor, you will need to have an ultrasound of that particular breast mass. If that image shows a mass that has an irregular outline or appears to have fuzzy edges and is pressing on the tissue around it, then you will need to have a biopsy done of the mass. An analysis of the tissue sample from the mass is the most accurate way to diagnose its actual nature.

What Causes Breast Tumors

Many factors may increase your risk for breast cancer, but we don’t yet know the exact cause. The BRCA 1 and 2 genes, when they are healthy, act as a tumor suppressor for breast and ovarian tumors. But you may inherit mutated BRCA genes, or those genes may become damaged from exposure to radiation or chemicals in your environment. Some genetic mutations develop as part of the cancer.

Risk Increases With Age

About 17 percent of women who were diagnosed with invasive breast cancer were in their 40s, and 78 percent of women with invasive breast cancer were older than 50.

View Article Sources
  • American Cancer Society. Breast Cancer: Early Detection, Importance of Finding Breast Cancer Early.
  • American Cancer Society. Do We Know What Causes Breast Cancer?