Breast cancer and cardiovascular outcomes after breast cancer in survivors of Hodgkin lymphoma

Background: Hodgkin lymphoma (HL) survivors treated with chest radiotherapy have an increased risk of breast cancer (BC). Prior HL treatment and associated cardiovascular disease (CVD) risk may limit BC treatment options. It is unknown how treatment adaptations affect BC and CVD outcomes. Methods: The authors compared 195 BC patients treated with chest/axillary radiotherapy for HL (BC-HL) with 5988 age- and calendar year-matched patients with first primary BC (BC-1). Analyses included cumulative incidence functions and Cox regression models, accounting for tumor characteristics and BC treatment. Results: Compared to BC-1 patients, BC-HL patients received anthracycline-containing chemotherapy (23.7% vs. 43.8%, p <.001) and breast-conserving surgery followed by radiotherapy (7.1% vs. 57.7%, p <.001) less often. BC treatment considerations were reported for 71% of BC-HL patients. BC-HL patients had a significantly higher risk of 15-year overall mortality than BC-1 patients (61% vs. 23%). Furthermore, risks of BC-specific mortality and nonfatal BC events were significantly increased among BC-HL patients, also when accounting for tumor and treatment characteristics (2.2- to 4.5-fold). BC-HL patients with a screen-detected BC had a significantly reduced (61%) BC-specific mortality. One-third of BC-HL patients had CVD at BC-diagnosis, compared to