A result that appears negative but fails to reveal a situation. An example of a false negative: a particular test designed to detect cancer of the breast is negative but the person actually has cancer. For screening mammography, it is important to know that not all breast cancers are seen. Another way of saying this is that mammography has a false negative rate of approximately 5-10%, meaning that out of every 100 women who actually have breast cancer, mammograms may not show it in 5-10 of the women. This is why we emphasize breast self-exams and annual physician breast exams in addition to mammography. Most women who might have a ”false negative” mammogram will have some other indication of the cancer on exam.

A result that is erroneously positive when a situation is normal. An example of a false positive: a particular test designed to detect breast cancer is positive but the person does not have breast cancer. For screening mammography, the false positive rate is actually quite high. Mammograms are usually classified by a BIRAD number, anywhere from 1-5. Those classified as “5” are highly suspicious for breast cancer, and nearly all of these will be “true positive”. Those classified as “4” are still suspicious, and biopsy is recommended, but only about 15% of these will be cancer. We would say that a BIRAD 4 mammogram is “positive”, but only about 1 in 6 women will actually have breast cancer. Ideally, we would not have to do that many biopsies to find the women who have cancer, but if don’t do the biopsies in this group, we won’t find the breast cancers as early as we would otherwise.

The family structure and relationships within the family, including information about diseases in family members. If there are a number of women in your family who have had breast cancer, or even one or two with breast cancer at a very early age, or have had both breast and ovarian cancer, you may be at risk for carrying one of the BRCA (breast cancer) genes. Breast cancer can “run in the family”, but only about 5% of breast cancers are clearly “in the family” based on genetic testing for BRCA.

A benign rubbery growth of tissue that is most commonly seen in teenagers and girls in their 20s. They can be multiple at times. Any “lump” in the breast can cause anxiety at any age, so it is no surprise that even if a doctor is confident that a lump is a fibroadenoma just based on its feel and perhaps by looking at it with ultrasound, they should nearly always be biopsied. Most of them are easily removed, and this may be the better option in many cases.