Breast Cancer in Young Women

Breast Cancer in Young Women

Although breast cancer is rare in young women, it can be an overwhelming diagnosis when added to this already busy time of life. However, you are not alone. More than 12,000 women under the age of 40 were diagnosed with breast cancer in 2015.

5 Facts about Breast Cancer in Younger Women:

  • The most common type of invasive breast cancer in young women is invasive ductal carcinoma, which is also the most common breast cancer in all women and men. In 2015, over 85% of young women diagnosed with invasive breast cancer had invasive ductal carcinoma. 
  • Triple Negative Breast Cancers (breast cancers that are lacking estrogen, progesterone and HER2 receptors) are more common in women under the age of 40.
  • Breast Cancers in young women are more likely to have a higher histological grade than older women.
  • Genetic mutations are more common among young women with breast cancer than among older patients with breast cancer.
  • Breast conservation therapy can be offered to many young patients with breast cancer.

Treatment Considerations

In general, treatment recommendations for young women are similar to those for any breast cancer patient with the same disease stage. Treatment decisions are usually based on the disease stage (tumor size, lymph node involvement), tumor grade, receptor status, and other tumor characteristics. Patient factors, such as menopausal status, fertility concerns, and other patient preferences may also be considered when planning the appropriate treatment. Surgery and radiation are often used to control the disease in the breast and lymph nodes (by removing and eliminating it) and to prevent recurrences in those places. Chemotherapy and other systemic therapies prevent and control disease elsewhere in the body. 


Many young women can safely undergo breast conserving surgery and radiation therapy to treat their breast cancer if their breast cancer is at an early stage. If a young woman is eligible for a lumpectomy, there is no survival benefit to choosing a mastectomy.

However, not all young women are good candidates for breast conserving therapy. One exception is young women with genetic mutations that cause breast cancer. These genetic mutations can either be inherited or a new spontaneous mutation. For these patients with genetic defects predisposing to breast cancer, bilateral mastectomies might be a better choice. If a mastectomy is recommended, most women will have the option to consider reconstructive surgery.

Factors influencing the surgical decisions include: tumor size, extent, location, cosmetic outcome, prior radiation, presence of a genetic mutation (such as BRCA), and patient preference.

Some women may also consider having the unaffected breast removed at the same time as the surgery for her breast cancer. This is called contralateral prophylactic mastectomy. While this is an option and may be recommended for some women (such as those with a BRCA mutation), it has not been shown to improve survival for women without genetic mutations.

Radiation Therapy

Young women who have a lumpectomy will require radiation therapy to the breast and possibly the nearby lymph nodes. If a mastectomy is done, most women do not need radiation. Factors influencing the radiation decisions are similar to those for surgery and may include: tumor size, extent, location, lymph node involvement, type of surgery performed, prior radiation or other contraindications to radiation, and patient preference. 


Chemotherapy recommendations for young women are based on breast cancer biology, disease stage, and the patient’s medical history. Current outcomes in treatment are similar across age groups and appear more similar regardless of age. Use of medication to suppress ovarian function in premenopausal women may also be considered so that fertility may be preserved.

Endocrine Therapy

Similar to chemotherapy, recommendations for hormone blocking therapy are based on disease stage and tumor biology, but in endocrine therapy age is considered a factor in choosing hormone blocking therapy. For example, postmenopausal women with hormone receptor positive tumors (ER/PR+) are often treated with aromatase inhibitors, but this particular treatment is not usually offered to young (premenopausal women) unless ovarian suppression is also part of treatment. Instead, most young women with hormone receptor positive (ER/PR+) disease are offered Tamoxifen, which will be recommended for five to ten years. 

Genetic Testing

Based on current guidelines, any woman diagnosed with breast cancer under the age of 45 should consider genetic testing. Genetic mutations that are associated with breast cancer are more common in young women with breast cancer. These harmful mutations account for 4-6% of all breast cancers in women under the age of 40. The most common genetic mutations causing breast cancer in young women are BRCA1 and BRCA2 mutations, although there are other mutations that are also associated with breast cancer in young women. Genetic testing is important because certain treatment decisions, such as choosing a bilateral mastectomy, may be influenced by the results. Also genetic mutations may put one at risk for other types of cancer besides breast cancer. If a patient is diagnosed with a genetic mutation, their close blood relatives (such as biological children, siblings, and parents) may also be at risk of having the genetic defect and should consider testing.

Clinical Trials

Depending on where you seek treatment, you may have the opportunity to participate in a clinical trial. Participating in a clinical trial may give you access to a treatment option that would not otherwise be available. Participation in a clinical trial is never mandatory, but may a good option for many women.

For those young women who face a breast cancer diagnosis know that you should:

Seek out the support you need. Don’t be afraid to ask questions. Get a team of caring healthcare professionals on your side. You are not alone.