Sociodemographic Factors Associated With Developing Head And Neck And Esophageal Cancers Following Breast Cancer.

e13063Background: Breast cancer survivors may develop other primary malignancies due to several factors. However, sociodemographic factors associated with the development of head and neck (HN) and esophageal second primary malignancies (SPMs) following management of primary breast cancer (BC) have not been well studied. This study examined the association between BC patients’ sociodemographic characteristics and the development of an esophageal or HN SPM. Methods: Patients (n= 505,641) diagnosed with breast cancer between 1973 and 2013 in the Surveillance, Epidemiology, and End Results (SEER) 9 program were used for this analysis. HN SPMs included oral cavity, pharynx, larynx, and sinuses. Cox proportional hazards regression was used to evaluate estimators of survival based on age at diagnosis, race, marital status, treatment type, and year of diagnosis. Results: A total of 284 BC patients developed an esophageal SPM, and 969 developed HN SPM. In the adjusted model, increased age at BC diagnosis was a sig...