Dense breast tissue shows up on a mammogram as solid white. However, tumors also show up on a mammogram as solid white, which makes it difficult to detect cancer.
Breast density is one of the strongest predictors of the failure of mammography to detect cancer. Mammography misses every other cancer in dense breasts.
The inability to detect breast cancer easily in dense breast tissue means that these women are often diagnosed in the late stage of breast cancer. This means the cancer is much harder to treat and the survival rates are a lot lower.
Fatty breasts on the other hand tend to be transparent on mammograms, which makes it a lot easier to spot cancer. About 40% of women have dense breasts.
Unfortunately, some doctors don’t tell patients if they have dense breasts in order to illicit extra caution.
At the moment, 24 states require doctors to notify patients with a letter. Twelve other states are considering similar legislation.
A recent study in the Annals of Internal Medicine discovered that offering an ultrasound to women with dense breasts after a clean mammogram does not improve breast cancer survival rates significantly. However, the use of ultrasounds after a clean mammogram does raise health care costs.
Breast density has been a well-established predictor of breast cancer risk. High breast density is a greater risk factor than having two first degree relatives with breast cancer.
The bottom line is that women need to ask their doctor questions and know about their bodies. It is important to keep up with monthly self-exams.
Women should see a health care provider if they notice any breast changes including but not limited to thickening inside the breast, swelling, redness, change in the size or shape of the breast, etc…