Why is it important for women to have breast screenings?

Short answer

Breast cancer is the most common cause of death from cancer in women worldwide and the second most frequent cause of cancer-related death in women in the U.S. Yet doctors encounter patients daily who are unclear on the details of prevention screening.

We do know that screening is most beneficial for people who are at high risk of developing breast cancer, but most people who develop breast cancer do not have significant risk factors. Here are the key questions you want to ask yourself and then discuss with your primary care doctor or gynecologist.

Am I at normal risk or high risk for breast cancer?
What type of screening would be best for me?
When and how often do I need screening?

Long answer

The biggest risk factors for developing breast cancer are being female and being older than 50 years old.

The red flags that put you in the high-risk category include:

Personal or family history of breast/ovarian cancer
Genetic predisposition (primarily BRCA)
Radiation to the head or chest prior to age 30
Significant family history of breast cancer

There are many other risk factors that moderately increase your chance of breast cancer, such as obesity, smoking, alcohol use, dense breast tissue, a sedentary lifestyle, starting your period prior to age 12, never breastfeeding, never being pregnant, having a first pregnancy after age 30, or taking certain forms of hormone replacement therapy.

Part of the confusion regarding breast cancer screening likely stems from the fact that there is not as much guideline consensus as one may expect. But the general recommendations are as follows:

Everyone agrees that women 50-74 should get a screening mammogram.
There is no consensus on screening for average-risk women age 75 and older (due to lack of data/evidence).
For women at a high risk of any age, most groups agree that screening should start at age 40 and include a yearly mammogram and MRI.
For women with dense breast tissue, there is not enough evidence for any specific recommendation.

The longstanding form of breast cancer screening that most people are familiar with is mammography. Other forms include SBE (self-breast exam), tomosynthesis (“3D mammograms”) and breast MRI. You should ALWAYS be seen by a physician quickly if you or your partner notice any abnormalities with your breasts (a lump, new or worsening asymmetry in size or shape, skin changes, breast itching or nipple discharge in a woman who is not breastfeeding).

So why not just do yearly mammograms or screening for all females starting at age 20? Well, as it turns out, there are actually a few downsides that you should be aware of. There is a small amount of radiation exposure (0.4 millisieverts), but this is not considered dangerous. The real concerns are overdiagnosis and false positives. Overdiagnosis means that a woman has a mammogram that discovers breast cancer, but in reality, the cancer is ‘pre-cancer’ or a small and slow-growing cancer that would have never caused a problem had it not been found.

Mammograms are still the most affordable and scalable option that we currently have. And we do know that in high-risk populations, mammograms absolutely make a difference.

Caveat

For the record, men can and do get breast cancer. If you have a male relative in your family with a history of breast cancer, that is an indication to see a geneticist for screening for genetic causes of cancer.