Surgical Management and Contralateral Breast Cancer Risk in Women with History of Radiation Therapy for Hodgkin Lymphoma: Results from a Population-Based Cohort

Background Women with history of chest irradiation for Hodgkin lymphoma are at increased risk of developing bilateral breast cancer, although contralateral breast cancer risk estimates in this population remain undefined. Methods We queried the SEER database for women treated with radiation therapy for Hodgkin lymphoma prior to age 30 years and were diagnosed with a subsequent breast cancer between 1990–2016. Trends in surgical management and the 5- and 10-year cumulative incidence of contralateral breast cancer were evaluated. Results The cohort included 295 women with a median age of 22 years (range 8–30 years) at Hodgkin lymphoma diagnosis, and 42 years (range 22–65 years) at breast cancer diagnosis. Overall, 263 (89.2%) presented with unilateral breast cancer, while 32 (10.8%) presented with synchronous bilateral breast cancer. Breast-conserving surgery was performed in 17.3% of patients, while mastectomy was performed in 82.7%. In 263 patients presenting with unilateral breast cancer, 50 (19.0%) underwent breast-conserving surgery and 213 (81.0%) underwent mastectomy. Subgroup analysis of mastectomy patients demonstrated a 40.5% bilateral mastectomy rate. The 5-year incidence of contralateral breast cancer in women who underwent unilateral surgery was 9.4% [95% confidence interval (CI), 5.6–15.4%], increasing to 20.2% (95% CI, 13.7–29.2%) at 10-year and 29.9% (95% CI, 20.8–41.9%) at 15-year follow-up. Conclusions Women with a history of prior chest radiation for Hodgkin lymphoma with a diagnosis of breast cancer have a 10-year contralateral breast cancer risk of 20%. These findings support consideration of contralateral prophylactic mastectomy during surgical decision-making for management of this high-risk patient population.