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.