Key clinical point: The risk for non-breast second primary cancer (SPC) at many sites was significantly elevated in female breast cancer (BC) survivors, particularly those who were first diagnosed with BC before the age of 50 years.
Major finding : The summary standardized incidence ratio (SIR) for non-breast SPC was estimated to be 1.24 (95% CI 1.14-1.36), with the risk being significantly higher among patients diagnosed with BC before vs after the age of 50 years (SIR 1.59 vs 1.13; P < .001). The risk for non-breast SPC was the highest at the thyroid (SIR 1.89; 95% CI 1.49-2.38), followed by corpus uteri, ovary, kidney, esophagus, skin (melanoma), blood (leukemia), lung, stomach, and bladder.
Study details: Findings are from a meta-analysis of one prospective and 27 retrospective studies.
Disclosures: This study was funded by the CRUK Catalyst Award CanGene-CanVar, UK. The authors declared no conflicts of interest.
Source: Allen I et al. Risks of second non-breast primaries following breast cancer in women: A systematic review and meta-analysis. Breast Cancer Res. 2023;25(1):18 (Feb 10). Doi: 10.1186/s13058-023-01610-x