Right now, breast cancer is the most common cancer in American women. There will be an estimated 266,120 cases of breast cancer diagnosed in US women this year, according to data from the American Cancer Society (ACS).
The encouraging news is that it’s become less deadly. The death rate for female breast cancer has declined by 39% since its peak in 1989, a reduction that’s been attributed to better treatment, early screening, and increased awareness, the ACS says.
But breast cancer awareness can be hindered by persistent myths and confusion surrounding the disease, its causes, screening tests, and more.
To sort through that confusion, INSIDER spoke with breast surgeon Dr. Deanna Attai, assistant clinical professor of surgery at UCLA’s David Geffen School of Medicine.
Here are 13 key facts about breast cancer that everyone should know.
1. Men can get breast cancer, too
Men can get breast cancer, but, it’s about 100 times more common in women, according to the American Cancer Society (ACS).
There will be an estimated 2,550 cases of male breast cancer in 2018, the ACS reports.
2. Lumps are the most common breast cancer symptom
Lumps are the most common symptom of breast cancer, according to the ACS.
If a breast cancer spreads to the lymph nodes, it may cause lumps and swelling around the collarbone or under your arm, even if the original tumour in the breast is still too small to be felt.
If you notice a lump, always see a doctor to have it checked out. Most breast lumps are benign, and some may go away on their own, but Attai previously told INSIDER that it’s “always reasonable” to have lumps checked.
3. But there are other possible symptoms, like skin changes and pain
The ACS adds that other symptoms may also signal breast cancer, including breast swelling; breast or nipple pain; the nipple turning inward; red, scaly, or thickening breast or nipple skin; and any nipple discharge that’s not breast milk.
4. Mammograms aren’t perfect, but they’re still important
In recent years, mammograms have been at the center of heated debate. Some people hold fast to the claim that the screening test, which is meant to catch breast cancer early using x-ray imaging, saves lives. But some news articles – citing newer research – say the exact opposite, arguing there’s no evidence mammography prevents breast cancer deaths.
Attai said the truth is somewhere in between. Part of of the problem, she explained, is that screening tests like mammograms are “one size fits all. They’re given to people across a huge age range, but as we age, breasts change in ways that can impact the effectiveness of mammography. For example: Mammograms aren’t as good as spotting tumours in dense breast tissue, which tends to occur in younger women, Attai said.
“A colon or cervix are more or less the same in a 40-year-old versus a 70-year-old,” she added. “A woman’s breast undergoes significant change during that time, and mammograms only work one way. When you really think about it, how in the world could they work for everybody? Even in one woman, over the course of her lifetime, the breasts are so different. So it’s a challenging area.”
Plus, mammograms can have harms. The test may pick up on non-cancerous changes (a.k.a a “false positive”), which typically means you have to undergo more imaging and testing that’s not actually necessary. This takes time and may ramp up anxiety, negatively affecting your wellbeing.
“Many women will go through all of that and they get a benign result and they say, ‘Phew, I’m so relieved,'” Attai said. “But some women will say ‘Great, so I went through all of that worrying and it turns out it was nothing.’ That’s where you have the potential downside.”
Right now, the American College of Obstetricians and Gynecologists (ACOG) recommends that women at average risk for breast cancer get mammograms every one to two years starting at age 40. But depending on your personal risk factors, you may need to be screened on a different schedule, starting at a different age. Attai said a gynecologist, primary care doctor, or a breast surgeon can help you make the best choice for you.
5. Some women may need additional screening tests
Attai explained that mammography is currently the only FDA-approved test to screen for breast cancer, but some women may also get breast ultrasounds or MRIs in addition to mammograms.
“Ultrasound can be used as a supplemental screening tool, especially in women with dense breast tissue,” she said. “MRI is primarily used for screening in women considered to be at high risk for breast cancer, such as those who carry the BRCA mutation or other genes that increase the risk of breast cancer.” (More on those in a bit.)
6. You don’t need to do breast self-exams on a rigid schedule
Doctors used to urge women to do breast self-exams to hunt for potentially problematic lumps, but that advice has since fallen out of favour.
Instead, experts now recommend an approach called breast self-awareness. It’s like a lot like watching your moles for potential signs of skin cancer.
Get to know how your breasts normally look and feel and keep an eye out for changes, but don’t feel like you need to perform self-exams on a rigid schedule, especially if doing so might make you anxious, Attai said. Just make sure you’re getting breast exams at your yearly check-up with a doctor, and see a doctor if you notice any concerning changes.
7. The two biggest risk factors for breast cancer are out of your control
There are plenty of risk factors that can influence your odds of developing breast cancer.
But it’s good to remember that the most important ones are out of our personal control.
“The biggest risk factors for breast cancer in this country are being a woman and getting older – something we are all doing,” Attai said.
8. There are some lifestyle habits that can influence your breast cancer risk
You may not be able to stop ageing, but there are some breast cancer risk factors you can control.
Drinking alcohol, being overweight or obese, being sedentary, using hormone therapy during not having children, and not breastfeeding can all increase breast cancer risk, according to the ACS.
But it’s important to remember that having a risk factor doesn’t mean you’re doomed to get breast cancer. And, on the flip side, Attai stressed that avoiding these risk factors doesn’t mean you’ll be immune to breast cancer, either.
“Some patients think, ‘I breastfed my children so I can’t get breast cancer;’ ‘It’s not in my family so I’m not at risk;’ ‘I eat healthy and don’t drink and don’t smoke so I’m not at risk,'” Attai said. “But all women are at risk.”
9. Wearing bras won’t give you cancer
Don’t believe the oft-circulated myth that wearing bras will somehow give you breast cancer. There’s no scientific basis for the claim, according to the ACS, and a 2014 study found no link between bra wearing and breast cancer.
10. There’s no evidence to suggest that deodorant causes cancer
Most deodorant/antiperspirants contain an aluminium-based compound that temporarily blocks sweat ducts. For years, blogs and chain emails have promoted the idea that these aluminium-containing deodorants cause breast cancer.
But there’s just no strong evidence to back up this idea, according to the ACS.
“I tell my patients, including my breast cancer patients, use what works,” Attai previously told INSIDER. “If it makes you feel better to not use aluminium-containing deodorant, that’s fine. But it might be a false sense of security to think that this practice will keep you from getting breast cancer. It probably is not having much of an impact on breast cancer risk.”
11. Most women diagnosed with breast cancer don’t have it in their family
Some women may think they’re not at risk for breast cancer if no one else in their family has had it, Attai explained. Unfortunately, that’s just not true.
“A family history increases your risk, but the majority of women newly diagnosed with breast cancer now don’t even have it in their families,” she said.
12. Some people have genetic mutations that increase breast cancer risk
Some people carry genetic mutations that can increase their odds of getting breast cancer. You’ve probably already heard about the BRCA1 and BRCA2 mutations. Research estimates that 71% of women with BRCA1 and 69% of women with BRCA2 mutations will develop breast cancer before age 80, while only 12% of women in the general population will get the disease during their lives, the National Cancer Institute explains.
Attai added that some other, less common gene mutations are also associated with varying increased risk for breast cancer, including CHEK2, ATM, and TP53.
A doctor may recommend testing for these mutations if you have certain risk factors, like a family history of breast cancer. Women who do have a mutation may undergo increased screening, take certain medications, or consider preventative surgery like mastectomy, which can reduce the risk of breast cancer development, Attai said.
“It is important that women who feel they may carry a genetic abnormality based on their family history to discuss this with their physician and/or a genetic counselor,” she added.
One final note: Even though direct-to-consumer genetic tests are growing in popularity, Attai said that many doctors have concerns about patients using them to test for breast cancer mutations, because the results can be difficult to interpret without the proper context and help from an expert, particularly a genetic counselor.
“One of the challenges with genetic testing is you don’t always get a positive or negative result. It’s not always that you have the mutation or you don’t,” Attai said. “The results most definitely need to be interpreted in the context of family history, and patients need some form of counseling.”
13. A study found a link between breast cancer and hormonal birth control, but the increased risk is very small
But in the actual jump in risk was small. The study, which followed 1.8 million women for more than 10 years, estimated that hormonal birth control caused an additional 13 cases of breast cancer per 100,000 women per year. (The difference was 55 cases versus 68.)
So it’s true that there may be a slightly increased risk of breast cancer when you’re using these methods of contraception, Attai said – but that slight increase doesn’t exist in a vacuum. It has to be weighed against your other breast cancer risk factors and the risk of unplanned pregnancy.
Plus, some types of hormonal birth control can decrease the risk of other cancers, like ovarian and uterine, and may provide other benefits like lighter, less painful periods, according to the ACOG.
The bottom line is that each birth control method has its pros and cons. If you’re having trouble deciding between them, your doctor can help you narrow down the options.
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