African American race as a risk factor associated with a second primary lung cancer after initial primary head and neck cancer

Background Initial primary head and neck cancer (IPHNC) is associated with second primary lung cancer (SPLC). We studied this association in a population with a high proportion of African American (AA) patients. Methods Patients with IPHNC and SPLC treated between 2000 and 2017 were reviewed for demographic, disease, and treatment-related characteristics and compared to age-and-stage-matched controls without SPLC. Logistic and Cox regression models were used to analyze the relationship of these characteristics with the development of SPLC and overall survival (OS). Results Eighty-seven patients and controls were compared respectively. AA race was associated with a significantly higher risk of developing SPLC (OR 2.92, 95% CI 1.35-6.66). After correcting for immortal time bias, patients with SPLC had a significantly lower OS when compared with controls (HR 0.248, 95% CI 0.170-0.362). Conclusions We show that AA race is associated with an increased risk of SPLC after IPHNC; reasons of this increased risk warrant further investigation.