Women diagnosed with breast cancer who carry germline pathogenic variants (PVs) in BRCA1, BRCA2, CHEK2, and PALB2 have an elevated risk for contralateral breast cancer (CBC), according to a study published in the Journal of Clinical Oncology. Siddhartha Yadav, MD, and colleagues prospectively followed 15,104 women treated with ipsilateral surgery for invasive breast cancer. The risk for CBC was estimated for women with versus without PVs in ATM, BRCA1, BRCA2, CHEK2, and PALB2. CBC risk was significantly elevated for germline BRCA1, BRCA2, and CHEK2 PV carriers with breast cancer (HRs, >1.9), while elevated risk was only seen for PALB2 carriers with estrogen receptor (ER)-negative breast cancer (HR, 2.9). No significant increased risk for CBC was seen for ATM carriers. Similarly elevated risks for CBC were seen for African-American and non-Hispanic White PV carriers. The 10-year cumulative incidence rates for CBC among premenopausal women were estimated at 33%, 27%, and 13% for
BRCA1, BRCA2, and CHEK2 PV carriers with breast cancer, respectively, and 35% for PALB2 carriers with ER-negative breast cancer.
