SOURCE:
This study, led by Kristen D. Brantley, PhD, from Harvard T. H. Chan School of Public Health, Boston, was published online in JAMA Oncology.
LIMITATIONS:
A small number of second breast cancer events limited the authors’ ability to assess the effects of multiple risk factors together. Data on risk factors might be incomplete. About 9% of participants completed abbreviated questionnaires that did not include information on body mass index, alcohol, smoking, and family history. Frequencies of pathogenic variants besides BRCA1 and BRCA2 may be underestimated.
DISCLOSURES:
This study received no external funding. Four authors reported receiving grants or royalties outside this work. Other reported no competing interests.
A version of this article appeared on Medscape.com.