Key clinical point: Women who survived cancer during childhood and received ≥ 200 mg/m2 cumulative doxorubicin dose as a part of the treatment may have an increased risk of developing subsequent breast cancer (SBC).
Major finding: A ≥200 mg/m2 cumulative doxorubicin dose vs no doxorubicin treatment led to > 2-fold increase in the risk for SBC (hazard ratio [HR] for 200-299 mg/m2: 2.50, 95% CI 1.85-3.40; HR for 300-399 mg/m2: 2.33, 95% CI 1.68-3.23; and HR for ≥ 400 mg/m2: 2.78, 95% CI 1.99-3.88). Every 100 mg/m2 increase in the cumulative doxorubicin dose increased SBC risk in patients who survived cancer and either received (HR 1.11; 95% CI 1.02-1.21) or did not receive chest radiotherapy (HR 1.26; 95% CI 1.17-1.36).
<Study details: Findings are from an analysis of a pooled cohort including 17,903 females who survived cancer for ≥ 5 years, of whom 782 survivors developed SBC.
Disclosures: This study was supported by the Children Cancer Free Foundation (aka Foundation KiKa, Stichting Kinderen Kankervrij), Amsterdam. The authors declared no conflicts of interest.
Source: Wang Y et al for The International Consortium for Pooled Studies on Subsequent Malignancies after Childhood and Adolescent Cancer. Subsequent female breast cancer risk associated with anthracycline chemotherapy for childhood cancer. Nat Med. 2023;29(9):2268-2277 (Sep 11). doi: 10.1038/s41591-023-02514-1