The Basics on Breast Cancer and Young Women

 “I’m too young for breast cancer!”

This may have been one of your first thoughts when your doctor told you about your diagnosisinfo-icon. Women under 40 do develop breast cancer, although at a lower rate than older women.

While breast cancer in young women is less common and often overlooked, it is still a major health concern:

  • Five percent of new breast cancers occur in women under 40. That’s a small percentage, but it represents a lot of women.
  • Each year, about 11,330 young women are diagnosed with invasive breast cancer and 1,780 with in situ disease, according to the American Cancer Society.

Understanding more about being diagnosed at a young age can help you move forward and make decisions that are best for you.

Young Age and Breast Cancer Risk

Because your breast cancer risk increases with age, your chances of developing invasive breast cancerinfo-icon are:

  • under age 40 — 1 in 203
  • age 40 to 59 — 1 in 27
  • lifetime risk — 1 in 8

African-American women have a higher chance of being diagnosed before age 40 than non-Hispanic white women. (After age 40, non-Hispanic white women are diagnosed at a higher rate than African-American women.) Hispanic, Asian/Pacific Islander and American Indian/Alaska Native have lower rates of diagnosisinfo-icon overall, but they are increasingly diagnosed at younger ages.

It’s normal to question why you developed breast cancer. You may feel unlucky and angry, but the breast cancer is not your fault.

Some reasons you could have been at higher risk for breast cancer include:

  • Your mother, father, sister or daughter was diagnosed with breast cancer, or you have other family history of breast or ovarianinfo-icon cancers on either your mother’s or father’s side.
  • You have a mutationinfo-icon, or change, on the BRCA1 or BRCA2 geneinfo-icon. Having a BRCA mutation increases your risk of breast and ovarian cancerinfo-icon. Between 5 and 10 percent of breast cancers are due to BRCA1info-icon or BRCA2info-icon mutations.
  • You had radiation therapyinfo-icon to the chest as a child, adolescent or young adult.
  • You had a high-risk breast lesioninfo-icon or prior breast cancer.

Reasons Young Women Develop Breast Cancer

In young women, certain factors can contribute to breast cancer development or create challenges for breast cancer detection or treatment.

Some of these age-related issues include:

  • Ignoring a breast lump or dischargeinfo-icon due to young age.
    • Healthcare providers and women may think a symptominfo-icon is related to menstrual cycleinfo-icon changes, a cyst, a blocked milk ductinfo-icon or something else that is not breast cancer.
  • Greater chances of delayed diagnosisinfo-icon until symptoms can be seen, and the cancer may be a higher stageinfo-icon.  
    • Young women may be told to watch a lump instead of having it analyzed.
  • More dense breast tissueinfo-icon, common in young women.
    • Density is due to the amount of glandinfo-icon tissue compared to fat tissue. It decreases as you age.
    • Lumps are difficult to feel in dense breasts. This increases the risk of breast cancer growing without being detected.
    • Mammograms are less effective at screeninginfo-icon dense breasts.  
  • Higher incidenceinfo-icon of BRCA1info-icon or BRCA2info-icon geneticinfo-icon mutations in younger women.
    • Having one of these geneinfo-icon changes increases your breast cancer risk.
  • Higher staginginfo-icon at diagnosis for young women.
    • Higher stage breast cancer can be more difficult to treat.
  • Tumorinfo-icon biology can be more aggressiveinfo-icon and resistant to treatment.
    • A greater percentage of breast cancers in young women are hormone receptorinfo-icon-negative for either estrogeninfo-icon (ERinfo-icon-), progesteroneinfo-icon (PRinfo-icon-), human epidermal growth factor negative (HER2-), or all three ( triple-negative).
    • Doctors cannot use some of the new targeted treatment options for triple-negative, ER- and HER2- breast cancers because they are not effective against them.
    • More African-American women have triple-negative breast cancerinfo-icon than other racial groups, contributing to lower survival.
  • Lack of a good screening tool.
    • Most women younger than 40 do not have regular mammograms because it is not standard medical practice. Those who do get screening are usually at high risk for breast cancer due to family history or a BRCA1 or BRCA2 mutationinfo-icon.

Among women diagnosed with breast cancer before age 40, the five-year relative survival rateinfo-icon is lower than for those who are diagnosed when older.

  • For younger women, 84 percent survive after five years, compared to 90 percent of women diagnosed after age 40.

Support After Diagnosis at a Young Age

Breast cancer is unwelcome at any life stageinfo-icon. That’s especially true when you’re young. You may be focused on your education, job and career, dating, developing a personal relationship, building a family or making plans for the future. 

A breast cancer diagnosisinfo-icon can leave you feeling isolated as well as shocked and worried. You may be the only woman your age among your friends, co-workers or family members who has been affected.

Certain issues are of special concern to younger women after a breast cancer diagnosis, including:

In the Young Women section of and throughout the website, you’ll find helpful information about these subjects and more.

To talk with another woman who has been there and understands, call our Breast Cancer Helpline. If you wish, we can match you with a Helpline volunteer who is your age or in a similar circumstance. Call us toll-free today: (888) 753-LBBC (5222).

This article was supported by Cooperative Agreement Number DP11-1111 from The Centers for Disease Control and Prevention. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention.

August 30, 2013
Reviewed By: