Myths and facts

There is an abundance of accurate information about breast cancer, but some incorrect ideas still hold sway. It’s important to stay informed, so that you know what the scientific evidence supports. Educate yourself about breast cancer and share the information with your loved ones, coworkers, family, and friends. Below are some common myths about breast cancer, corrected.

1. Myth: Most breast lumps are cancerous.

Reality: Roughly 80 per cent of lumps in women’s breasts are caused by benign (noncancerous) changes, cysts, or other conditions (via Women’s Health Matters). Doctors encourage women to report any changes at all, however, because catching breast cancer early is so beneficial. Your doctor may recommend a mammogram, ultrasound, or biopsy to determine whether a lump is cancerous. Click here to learn more about breast cancer screening.

2. Myth: Only women with a family history of breast cancer are at risk.

Reality: Many women diagnosed with breast cancer have no identifiable risk factors for the disease. But the family-history risks are these: If a first-degree relative (a parent, sibling, or child) has had or has breast cancer, your risk of developing the disease approximately doubles (via Project Health). Having two first-degree relatives with the disease increases your risk even more. For more on genetics and your risk of having breast cancer, click here.

3. Myth: Wearing an underwire bra increases your risk of getting breast cancer

Reality: No research shows that wearing an underwire bra increases your risk of breast cancer.

4. Myth: Wearing antiperspirant increases your risk of getting breast cancer.

Reality: A study published in the Journal of the National Cancer Institute in October 2002 found that breast cancer risk did not increase with the use of antiperspirant or deodorant, the use of a product right after removing underarm hair with a razor, or the use of products within one hour after shaving.1

Several years ago, research published in the Journal of Applied Toxicology found an ingredient called parabens in 20 human breast tumours.2 Parabens are preservatives used in many cosmetic products (including antiperspirant). The research stated that parabens have been known to act like estrogen, which can speed up the growth of breast cancer tumours. Though the research findings of the small study are interesting, more research needs to be done.

5. Myth: Exposing a tumour to air during surgery causes cancer to spread.

Reality: There is no evidence to support the idea that exposing a tumour to air during surgery causes cancer to spread. People may believe this because they feel worse after surgery than they did before. However, it is normal to feel this way when recovering from any surgery. Sometimes people may believe this myth when during surgery it is discovered that the cancer is more advanced than was expected based on the pre-surgery scans and x-rays. In these cases, the cancer was already there, but the original tests did not show its extent.

6. Myth: Breast implants can raise your cancer risk.

Reality: Women with breast implants are at no greater risk of getting breast cancer, according to research. Standard mammograms don’t always work as well on women with implants; however, so additional X-rays are sometimes needed to more fully examine breast tissue.

7. Myth: All women have a 1-in-8 chance of getting breast cancer.

Reality: The absolute risk of developing breast cancer during a particular decade of life is lower than 1 in 8, but your risk increases as you get older. For example, the risk of developing breast cancer in the next ten years is as follows:3

  • 13 out of 1,000 women in their 40s
  • 23 out of 1,000 women in their 50s
  • 29 out of 1,000 women in their 60s
  • 31 out of 1,000 women in their 70s

8. Myth: Small-breasted women have less chance of getting breast cancer.

Reality: There’s no connection between the size of your breasts and your risk of getting breast cancer. Very large breasts may be harder to examine than small breasts, with clinical breast exams—and even mammograms and MRIs—more difficult to conduct. But all women, regardless of breast size, should commit to routine screenings and checkups.

9. Myth: Breast cancer always comes in the form of a lump.

Reality: A lump may indicate breast cancer (or one of many benign breast conditions), but women should also be on the alert for other kinds of changes that may be signs of cancer. These include swelling; skin irritation or dimpling; breast or nipple pain; nipple retraction (turning inward); redness or thickening of the nipple or breast skin; or a discharge other than breast milk.

Breast cancer can also spread to underarm lymph nodes and cause swelling there before a tumour in the breast is large enough to be felt. On the other hand, a mammogram may pick up breast cancer that has no outward symptoms at all.

Read more about signs and symptoms of breast cancer.

10. Myth: You can’t get breast cancer after a mastectomy.

Reality: Some women do get breast cancer after a mastectomy, sometimes at the site of the scar. Or the original cancer may have spread. For women at high risk of breast cancer who have their breasts removed as a prophylactic or preventive measure, there’s still a chance, though a small one, that they can get breast cancer. For women with a BRCA mutation, surgical removal of both breasts is often recommended; this procedure can reduce the risk of  breast cancer by 90 per cent.4

11. Myth: Your father’s family history of breast cancer doesn’t affect your risk as much as your mother’s.

Reality: Your father’s family history of breast cancer is just as important as your mother’s in understanding your risk. If you have a female relative with breast cancer, this seems to increase your risk more than if you have a male relative with breast cancer. However, it doesn’t matter whether the relative is on your mother’s side or on your father’s.5

While men do get breast cancer, women are more vulnerable to it. Associated cancers in men (such as early-onset prostate or colon cancer) on either side are also important to factor in when doing a full family-tree risk assessment.

12. Myth: Caffeine causes breast cancer.

Reality: No causal connection has been found between drinking caffeine and getting breast cancer; in fact, some research suggests that caffeine may actually lower your risk. So far it’s inconclusive whether breast soreness may be linked to caffeine.

13. Myth: If you’re at risk for breast cancer, there’s little you can do but watch for the signs.

Reality: There’s a lot that women can do to lower their risk, including losing weight if they’re obese, getting regular exercise, lowering or eliminating alcohol consumption, being rigorous about examining their own breasts, and having regular clinical exams and mammograms. Quitting smoking wouldn’t hurt either.

Some high-risk women also choose to have a prophylactic mastectomy to decrease their risk by roughly 90 per cent. They can take other proactive steps such as having regular MRIs, exploring chemoprevention with treatments such as tamoxifen, and participating in clinical trials.

14. Myth: Women with lumpy breasts (also known as fibrocystic breast changes) have a higher risk of developing breast cancer.

Reality: In the past, women with lumpy, dense, or fibrocystic breasts were believed to be at higher risk of getting breast cancer. These women should be aware that their mammograms may be difficult to read and interpret, but there doesn’t appear to be a connection after all. When you have lumpy breasts, it can be trickier to differentiate normal tissue from cancerous tissue during traditional mammograms, so you may experience false alarms. John Hopkins Medicine recommends women with lumpy, dense, or fibrocystic breasts often follow up their mammograms with an ultrasound. It is recommended women with fibrocystic breast tissue choose a breast center that offers digital mammography. Digital mammograms address breast tissue density by allowing the radiologist to change the contrast of light and dark on the computer. It also allows the radiologist to enlarge an area of the breast tissue on the screen to more closely examine any areas of concern.

15. Myth: Annual mammograms expose you to so much radiation that they increase your risk of cancer.

Reality: While it’s true that radiation is used in mammography, the amount is so small that any associated risks are tiny when compared to the huge preventive benefits reaped from the test. Mammograms can detect lumps well before they can be felt or otherwise noticed, and the earlier that lumps are caught, the better one’s chances for survival.

Whatever your age, it is important to pay close attention to your breasts for any changes. The frequency of mammograms and the recommended age to receive them is a controversial topic – the Canadian Cancer Society recommends:

  • If you are 40 to 49, talk to your doctor about your risk of breast cancer, along with the benefits and risks of mammography.
  • If you are 50 to 69, have a mammogram every 2 years.
  • If you are 70 or older, talk to your doctor about how often you should have a mammogram.

16. Myth: Needle biopsies can disturb cancer cells and cause them to spread to other parts of the body.

Reality: There’s no conclusive evidence for this claim. A study of more than 2,000 cancer patients by researchers at Mayo Clinic’s campus in Jacksonville, Florida, has dispelled the myth that cancer biopsies cause cancer to spread. In the Jan. 9, 2015 online issue of Gut, they show that patients who received a biopsy had a better outcome and longer survival than patients who did not have a biopsy. The benefits of being diagnosed early far outweigh the risks of having a biopsy. If you have any questions or concerns about having a biopsy, ask your health care provider beforehand.

17. Myth: After heart disease, breast cancer is the nation’s leading killer of women.

Reality: Breast cancer kills roughly 5,000 women a year in Canada; however, lung cancer, heart disease, stroke, and chronic lower respiratory disease are each responsible for more deaths annually.

It is projected that 5,100 women will die from breast cancer in 2020. For comparison, 10,200 women are projected to die from lung cancer in 2020;6 heart disease was the cause of death for 23,437 women in 2013, stroke for 7,857 women, and chronic lower respiratory disease for 5,946 women.7

18. Myth: If your mammography report is negative, there is nothing else to worry about.

Reality: Despite their importance for breast cancer screening and diagnosis, mammograms fail to detect around 10 per cent to 20 per cent of breast cancers. This is why clinical breast exams and, to some extent, breast self-exams are crucial pieces of the screening process.

19. Myth: Hair straighteners and hair relaxers cause breast cancer in African-American women.

Reality: Researchers from Boston University and Howard University Cancer Center found no increase in breast cancer risk due to the use of hair straighteners or relaxers. Study participants included 48,167 African-American women who had used straighteners seven or more times a year for 20 years or longer. You can find the full study here: Hair Straightening Chemicals Not Linked To Breast Cancer Risk In African-Americans.

20. Myth: Removing the entire breast gives you a better chance of surviving cancer than having a lumpectomy with radiation therapy.

Reality: Survival rates are about the same for women who have mastectomies and for women who choose the breast-conserving option of removing only part of the breast (lumpectomy) and following the surgery with radiation therapy. However, there are some cases—such as with very ductal carcinoma in-situ (DCIS), the presence of BRCA gene mutations, or especially large tumours—where lumpectomy and radiation may not be an appropriate treatment option.

21. Myth: Overweight women have the same breast cancer risk as other women.

Reality: Being overweight or obese does increase your breast cancer risk—especially if you’re past menopause or if you gained weight later in life. More information on breast cancer risk factors related to body weight: Healthy Body Weight (Sunnybrook Health Sciences Centre).

22. Myth: Fertility treatments increase the risk of getting breast cancer.

Reality: Given estrogen’s connection to breast cancer, fertility treatments have come under suspicion. But several studies have found that women who receive fertility treatments seem not to have a higher risk of breast cancer. As yet, no large, long-term, randomized studies have eliminated this concern entirely; more research is warranted. There is a need for studies that follow women who have undergone IVF for longer periods of time. Moreover, it is very difficult in clinical research to control for the possibly different effects of different fertility treatments and the additional potential risk factors associated with reasons for seeking fertility treatment. For more information, read ‘Does Fertility Treatment Raise Breast Cancer Risk?’ ( See also this editorial in the JNCI: Breast Cancer Risk After Use of Fertility Drugs: Stimulating New Controversy.

23. Myth: Living near power lines can cause breast cancer.

Reality: There is no conclusive evidence of a relation between the electro-magnetic fields from power lines and cancer. What little evidence exists is very weak. There is a kind of radiation that can cause cancer, namely ionizing radiation, but power lines do not emit this kind. It’s also important to note that you would have to be very near a power line to get much exposure to its electro-magnetic field, because the strength of the field decreases very rapidly as distance from the source increases. In any case, there is no basis for any claims that living near power lines can cause breast cancer. You can read more from the U.S. National Cancer Institute about electro-magnetic fields and cancer. See also this booklet on electro-magnetic fields from the U.S. National Institute of Environmental Health Sciences.

24. Myth: Having an abortion raises your risk of getting breast cancer.

Reality: Because abortion is believed to disrupt hormone cycles during pregnancy and breast cancer is linked to hormone levels, numerous studies have investigated a causal link—but found no conclusive evidence for one. For example, a French cohort study of more than 100,000 women, “Induced and spontaneous abortion and breast cancer risk: Results from the E3N cohort study published in 2003, found no link between induced abortion and breast cancer risk. “Incomplete pregnancy is not associated with breast cancer risk: the California Teachers Study” also reported on more than 100,000 women in 2008. Researchers had asked the women in 1995 about past induced and spontaneous abortions. There was no difference in breast cancer risk between the group who had either spontaneous or induced abortions and those who had not had an abortion. Other cohort studies have looked specifically at the possible link between abortion and breast cancer in African-American women and in women who are at increased risk of breast cancer because they have mutations in the BRCA genes. These studies also did not find a link.

25. Myth: Breast cancer is preventable.

Reality: Alas, no. Although it is possible to identify risk factors (such as family history and inherited gene mutations) and make lifestyle changes that can lower your risk (such as by reducing alcohol consumption, losing weight, getting regular exercise, and quitting smoking), roughly 70 per cent of women diagnosed with breast cancer have no identifiable risk factors, meaning that the disease occurs largely by chance and according to as-yet-unexplained factors.

26. Myth: Family history is the biggest risk factor for cancer (via BC Cancer Agency).

Reality: Age is the biggest risk factor for most types of cancer. About seven of ten cancers occur in people aged 60 years or older.

More from How to help a loved one cope with breast cancer


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