“…Furthermore, a number of factors potentially mediate the race-survival association, including histologic type, smoking, and comorbidities. Studies have reported racial differences in lung cancer histologic type, 28,31 which is strongly associated with smoking, 20,33 and common lung cancer comorbidities such as COPD. 34,35 Although we adjusted for these factors, which is often lacking in other studies, we could not account for details such as packyears, smoking duration, and severity of comorbidities, which are more relevant predictors of survival.…”