Women who develop breast cancer when they’re relatively young – under age 45 – face a variety of issues unique to their stage of life. Questions about how the disease may affect their careers, relationships, sexual functioning, and ability to have and raise children often become pressing in the aftermath of a diagnosis.
Because breast cancer is relatively rare in young women – the average age at which the disease is diagnosed in the United States is 61 – there has been little research focused on young women, and such research is needed, ranging from the biology of the disease in younger patients to the particular challenges they encounter. To begin to fill in that gap, we launched the Young Women’s Breast Cancer Study in 2006, the first multi-institutional effort to track the medical and psychosocial issues faced by a large group of young women with breast cancer in the U.S.
The study enrolled more than 1,300 women across the country. Participants were surveyed at the time of their diagnosis and treatment, and continue to be surveyed post-treatment about issues such as fertility concerns, sexual functioning, body image, genetic testing, treatment decisions, and family planning. Participants were also asked to provide blood and tissue samples for analyses to better understand the biology of breast cancer in young women.

Data collected by the study have significantly increased our understanding of the nature of the disease in younger women and how it impacts their lives. Research based on the data may help change not only the way breast cancer is treated in these patients, but also the support services they receive.
Here are some of the most intriguing findings to date from studies using the Young Women’s Breast Cancer Study data.*
- A substantial portion of young women with hormone receptor-positive breast cancer had high grade, more aggressive tumors.
- A higher percentage of breast tumors in young women were HER2-positive versus those in older women. The HER2 protein spurs cancer cell growth and is a target for some drugs.
- There was no association between the age at which participants were last pregnant, or were ever pregnant, and the molecular subtype of cancer they developed.
- Participants sought care in a timely fashion. The median period between detecting a suspicious breast lump, or other symptom, and seeking care from a physician was only two weeks.
- Genetic testing rates are increasing. Seventy-seven percent of participants diagnosed with breast cancer in 2006 agreed to be tested for mutations in the BRCA genes, which increase the risk of future breast and/or ovarian cancer. By 2013, that figure had risen to 95 percent.
- An increasing percentage of young women with cancer in one breast are choosing to have the unaffected breast removed. The vast majority of study participants who chose this option said they did so to decrease the chance of developing cancer in the second breast, but many believe it will improve their survival. Research has shown that for women with breast cancer on one side, having the other breast removed does not improve survival.
- Thirty-eight percent of participants said that, prior to their diagnosis, they’d been interested in having children. At the time of diagnosis, twenty-six percent indicated such an interest. Although the percentage declined in succeeding years, it remained in the 25 percent range for the first three or four years after diagnosis.
- 11 percent of participants had taken steps to preserve their fertility by freezing embryos, freezing eggs, or other techniques.
- Other studies have sought to gauge young women’s fertility following breast cancer treatment, using menstrual periods as a marker of their ability to have children. Among patients under 30, 87 percent continued to have periods, as did 64 percent of those aged 36-40. All patients not treated with chemotherapy continued to have periods in the initial years after diagnosis, as did 60 percent of those who did receive chemotherapy.
- Of the participants who tried to get pregnant following treatment, the vast majority succeeded.
*Some of the earliest of these studies were based on data from only a portion of the 1,300 women who eventually enrolled. Follow-up studies will use data from the entire cohort.
Learn more from the Young and Strong Program for Young Women with Breast Cancer at Dana-Farber Cancer Institute.