TOPLINE:
METHODOLOGY:
- Investigators reviewed 28,649 Swedish women diagnosed with breast cancer from 1991 to 2019.
- Overall, 5,081 patients (17.7%) had at least one female first-degree relative previously diagnosed with breast cancer.
TAKEAWAYS:
- After adjusting for demographics, tumor characteristics, and treatments, a family history of breast cancer was associated with a lower risk of breast cancer–specific death in the full cohort (hazard ratio, 0.78) and in ER-negative women (HR, 0.57) within 5 years of diagnosis, after which point the association was no longer significant.
- The lower risk of death among women with a family history could mean that these women are more motivated and likely to get screened, potentially catching tumors earlier, and may be more likely to adhere to treatment recommendations.
- However, having a family history of early-onset breast cancer (before the age of 40) was associated with a higher risk of breast cancer–specific death (HR, 1.41).
IN PRACTICE:
Although the findings are reassuring for many women with breast cancer, “genetic testing of newly diagnosed patients with early-onset family history may provide useful information to aid treatment and future research,” the researchers concluded.
STUDY DETAILS:
The study was led by Yuqi Zhang, PhD, of the Karolinska Institutet, Stockholm, and published in JAMA Network Open.
LIMITATIONS:
- The main analysis did not include tumor characteristics only available within the last 20 years, including ERBB2 status.
- Relatively wide confidence intervals make the association between a family history of early-onset breast cancer and higher risk of breast cancer death somewhat uncertain.
DISCLOSURES:
- The work was funded by the Swedish Cancer Society and others.
- The investigators report no relevant financial relationships.
A version of this article originally appeared on Medscape.com.
