Risk of male breast cancer after Hodgkin lymphoma.

Female Hodgkin lymphoma (HL) survivors treated with chest radiotherapy have a strongly increased risk of breast cancer (BC), but the treatment-specific risk of BC in male HL survivors has not been evaluated. We assessed BC risk in a cohort of 3,077 male five-year HL survivors treated at age ≤51 years in 20 Dutch hospitals between 1965- 2013. We estimated standardized incidence ratios (SIRs), absolute excess risks per 10,000 person-years, and cumulative BC incidences. After a median follow-up of 20 years, we observed eight male BC cases. Male HL survivors experienced a 23-fold (95%CI: 10.1-46.0) increased BC risk compared with the general population, representing 1.6 (95%CI: 0.7-3.3) excess BCs per 10,000 person-years. The 20- and 40-year cumulative BC incidences after HL treatment were 0.1% (95%CI: 0.02-0.3), and 0.7% (95%CI: 0.3-1.4), respectively. Treatment with chest radiotherapy without alkylating chemotherapy yielded a strongly increased SIR (20.7; 95%CI: 2.5-74.8); the SIR for chest radiotherapy and alkylating chemotherapy was not significantly different (41.1; 95%CI: 13.4-96.0). Males treated with chest radiotherapy and anthracyclines had a SIR of 48.1 (95%CI: 13.1-123.1). Two patients died from BC (median follow-up 4.7 years). To ensure early diagnosis and treatment, clinicians should be alert to BC symptoms in male HL survivors.