Surprising Facts About Breast Cancer

October is Breast Cancer Awareness Month. Here are 10 things you might not know about breast cancer:

1. You may know that one in eight women in the U.S. will have breast cancer in their lifetime. But did you know that 75% of women with breast cancer have no or distant family history or other obvious risk factors?

Whatever is causing these breast cancers seems to be related to the environment and is hard to avoid. Even those of us who are trying to exercise, eat healthy and not smoke are still being diagnosed. The good news is that we can find most of these cancers while they are small and curable if we are screening.

2. Early detection still matters. If breast cancer is found when it is a centimeter or less and contained completely within the breast, the five-year survival rate is 99% and the treatment needed is more minimal. But once the cancer has spread beyond the breast and lymph nodes to other parts of the body, such as the lungs, liver and bones, the five-year survival rate is only 30% — even with modern treatments available. Most one-centimeter cancers cannot be felt on a physical exam, even in retrospect, so screening is vital to find breast cancer this small.

3. There are different types of breast cancer. In situ vs. invasive. Ductal vs. lobular. ER+ (luminal A and luminal B) vs. Her2+ vs. triple negative. The type significantly influences treatment and prognosis. Triple negative is the most aggressive, but 91% are curable if it is small.

4. Not all breast cancers make balls. Many grow like roots or vines. Fortunately, even though we can't feel these cancers, we can often see them on the mammogram.

5. White women have a slightly higher incidence of breast cancer, but Black women are more likely to have aggressive triple negative cancer and are more likely to be diagnosed at an early age. Black women are also more likely to die from their breast cancer. Work is needed to decrease this disparity. Annual mammographic screening beginning at age 40 is recommended for all women.

6. Why do we squeeze like that on a mammogram? Yes, it is partly to spread things out so that we can see better. But there is another important reason: the thinner we get the breast, the lower the radiation dose. Radiation doses from current mammograms are low-equivalent to about seven weeks of the normal low background radiation we get every day.

7. Dense breasts are normal. About 40% of women have breasts that look dense, or cloudy, on their mammogram. Dense tissues make it harder to see cancer. Dense breasts also grow more breast cancers. Mammograms are still important for these women, though, because there are cancers and high risk lesions that only show on the mammogram, even in dense breasts. Three-dimensional mammograms and whole breast ultrasounds help, but more is needed. New technologies, like abbreviated breast MRI and contrast-enhanced mammography, are being studied.

8. Screening is no longer one-size-fits-all. Women are now divided into average, intermediate and high-risk groups. The women in the high-risk group have the option to have additional screening with breast MRI, and some qualify to take medication for five to 10 years to decrease their risk of developing breast cancer.

9. Genetic testing has advanced. In the past, we could test for only two genes, BRCA1 and BRCA2. It was a blood test, and it was expensive. We can now test for dozens of genes related to breast cancer and other cancers. This is done by a saliva test, and for many women, it is now covered by insurance.

10. There is a new law in Maryland for diagnostic coverage. Starting in January 2024, Maryland-regulated insurers can no longer charge copays, coinsurance or deductible payments for diagnostic mammograms and breast ultrasound.