National Mammography Day: All Your Mammogram And Breast Cancer Screening Questions, Answered By Medical Experts

Breast cancer screening for women at average risk, it should be done every other year beginning at age 40, meaning mammograms should start ten years earlier than previously recommended.

The U.S. Preventive Services Task Force, an independent panel of national experts, released that finalized guidance on April 30, strengthening the same draft guidance issued last year. 

The task force estimates the change could save nearly 20% more lives from the disease.

Aside from skin cancers, breast cancer is the most common cancer in women in the United States, according to the American Cancer Society, accounting for about 30% of all new female cancers each year.

To help better understand the process, we've gathered answers to the most common mammogram and breast cancer screening questions:

What are mammograms?

A mammogram is an X-ray picture of the breast used to look for early signs of breast cancer. 

Standing in front of a special X-ray machine, your breast will be firmly pressed between two plates to flatten it and hold it still while the X-ray is being taken, the Centers for Disease Control and Prevention explains. 

"You will feel some pressure. The steps are repeated to make a side view of the breast. The other breast will be X-rayed in the same way," the CDC says.

The agency notes that a mammogram is "the best way to find breast cancer" for most women of screening age. 

What about screening with breast ultrasound or MRIs?

Mammograms are the most widely used type of screening exam, but there are other methods.

A breast MRI, which uses magnets and radio waves to take pictures, may be used with mammograms to screen women at high risk for breast cancer.

A breast ultrasound, which uses sound waves and their echoes to make computer pictures of the inside of the breast, can show certain changes that can be harder to see on mammograms, the American Cancer Society adds.

Though it is not typically used as a routine screening test, it can be helpful for women with dense breast tissue or those at higher risk.

"One of the more important reasons to have supplemental screening is because of women who are at higher risk of getting breast cancer, so women who have genetic mutations or a very strong very history," says Dr. Toma Omofoye, a breast imaging radiologist at the MD Anderson Cancer Center. "These are candidates who we screen with additional modalities beyond mammogram."

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What does dense breast tissue mean?

Breast density is a measure of how much fibrous and glandular tissue there is in your breast compared to fat tissue, the American Cancer Society explains. 

About half of American women over the age of 40 are considered to have dense breasts — and having this type of tissue is linked to a higher risk of developing breast cancer, although experts are not sure why. Denser tissues also make it more difficult to spot signs of cancer on a mammogram. For this reason, additional screening using an MRI or ultrasound may be advised. 

"Having dense breast tissue is common. Some women have more dense breast tissue than others. For most women, breasts become less dense with age. But in some women, there's little change," the American Cancer Society's website states.

It's also a common misconception that dense breast tissue depends on how your breast feel, Omofoye says.

"A lot of people will say, 'I know I have dense breasts because it feels lumpy to me.' That was actually not accurate. We can only know if your breast tissue is dense by the definition used by professionals based on how it photographs on a mammogram."

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Do mammograms hurt?

Though mammograms can feel uncomfortable, getting one is usually not a painful process.

"It's sort of awkward," Dr. Céline Gounder, a CBS News contributor and editor at large for public health at KFF Health News, shared recently on "CBS Mornings." "You have your breasts compressed between two plates, but it's not painful."

The CDC notes any discomfort is over soon, as a mammogram doesn't take long.

"What you feel depends on the skill of the technologist, the size of your breasts, and how much they need to be pressed," the CDC adds. 

There are also things you can do beforehand to reduce the likelihood that it's uncomfortable.

For example, Omofoye suggests scheduling it two to 10 days after your period, when your breasts are less sensitive. She also advises reducing your caffeine intake in the weeks before a mammogram to help with sensitivity. 

What can you expect, how can you prepare for mammograms?

The entire mammogram process takes about 20 minutes, including being called back to the room and taking your history, Omofoye estimates. 

The actual imaging takes a couple seconds at a time and involves a few rounds of the breasts being compressed, released and repositioned for the necessary angles. This means there are some short breaks in between. 

There are also things you can do to make the process go more smoothly, Omofoye says, including: 

1. Wearing a two-piece outfit.
2. Being as flexible as you can so they can image as much of the breast tissue as possible, since "our breast is not just the part that goes into your bra," Omofoye explains, but also includes tissue that sits closer to your chest wall. 
3. Being vocal, including expressing any concerns or history you may have, and telling the provider about any physical limitations they should be aware of (such as issues with your shoulders, for example) so they can work with you to get the best images possible.
4. Being prepared for the technologists to work with you pretty intimately. 

"Our technologists will work with them very closely to get them in the right position in the machine," Omofoye says. "It's something that is a necessary part of the examination and I just want women to be aware of it so that they're not surprised."

Can mammograms cause cancer?

No. "A mammogram does not give you breast cancer, it's really important to know," Gounder says. "A lot of times people will say to me, 'that test gave me such-and-such disease,' and no, it helps you find out that you have it (and) it helps you get care more quickly if you have it."

Because mammograms are X-ray tests, they do expose the breasts to low amounts of radiation, the American Cancer Society explains. 

"The benefits of mammography outweigh any possible harm from the radiation exposure. Modern machines use low radiation doses to get breast X-rays that are high in image quality," the organization's website states, noting that people in the U.S. are exposed to some radiation each year just from their natural surroundings. 

Can you get a mammogram while you're breastfeeding?

Mammography can be done safely for those breastfeeding and even sometimes for pregnant patients, Omofoye says.

"The dose of radiation to the breast from a mammogram is very, very small," she says, meaning it shouldn't discourage people from obtaining any necessary mammograms.

She does advise sharing that you've been breastfeeding while making your appointment, however, as there are often some additional steps that can be helpful. 

"We generally want to try to empty the breasts of milk before we take the mammogram picture," she says, adding they will often advise patients to come with a breast pump and try to pump before they take images.

What age should you start getting regular mammograms?

The U.S. Preventive Services Task Force's official recommendation is for screenings every other year starting at age 40 for women at average risk. That's 10 years earlier than the panel previously recommended in 2016. Before, the recommendation was for women in their 40s to make an individual decision about screenings based on their health history.

Other organizations already recommended annual mammograms before age 50.

The American College of Obstetricians and Gynecologists recommends beginning mammograms at age 40, every year or two, while the American College of Radiology advises getting one each year beginning at 40. The American Cancer Society recommends yearly mammograms starting at age 45, with the option to start earlier based on the individual's preference. 

What age can you stop getting regular mammograms?

In their latest guidance, the task force says more research is needed on the benefits and harms of screening women older than 75. Instead, the group advises making a decision with your doctor based on health needs and history. 

According to the American Cancer Society, screening should continue as long as a woman is "in good health and is expected to live at least 10 more years."

Omofoye says she follows guidance that women can get screened as long as they're healthy enough to be treated for breast cancer.

"For us, we do not have a firm stop date," she says. "We actually do not have women stop at 75 or any other external marker, because we know that women are continuing to live longer lives and live healthily at those later years. So we really want to evaluate a patient's health and see, if breast cancer was found at that age, would the patient be strong enough and interested in undergoing treatment."

Are there concerns with overdiagnosis and overtreatment?

With earlier screening guidance, some doctors have pointed out concerns about overdiagnosis and overtreatment.

"The issue here is to balance the need for early detection with the problem of overdiagnosis and overtreatment," Dr. Jules Cohen, a medical oncologist at Stony Brook Cancer Center, told CBS News. "We can hopefully split that difference by doing some sort of risk stratification so that we don't overtreat just because we find something early."

Omofoye thinks concerns about overdiagnosis are overemphasized, pointing to rates being around 10% or less, meaning of 10 cancers found, one may not cause harm if left alone.

"We can't predict which of those 10 cancers would be the overdiagnosed one versus the others that do need to be treated," she says. "The benefits of treating outweigh the risks of overdiagnosis, and the benefits of screening outweigh this harm."

The bottom line? Omofoye thinks it's better to be safe than sorry.

Does insurance cover mammograms?

The CDC says most health insurance plans are required to cover mammograms every one to two years beginning at age 40 with no out-of-pocket cost.

While the Affordable Care Act provides free mammograms under these specifications, many people can be hit with unexpected bills for second looks and follow-up tests.

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