Stram DO, et al. - Researchers focused on the disparities in lung cancer risk in the Multiethnic Cohort study. They previously reported the highest lung cancer risk among African Americans and Native Hawaiians vs Japanese Americans and Latinos; whites were in the middle in terms of risk. In this current study, they apportioned lung cancer risk into age-specific background risk (among never smokers), an excess relative risk term for cumulative smoking, and modifiers of the smoking effect (race and years-quit smoking). They used data from a urinary biomarker substudy to determine the impact of replacing self-reports of cigarettes per day (CPD) with a urinary biomarker—total nicotine equivalents. Findings revealed the persistence of racial variances in lung cancer risk in the Multiethnic Cohort study. These discrepancies were not explained easily by disparities in self-reported or urinary biomarker-measured smoking intensities. For lung cancer due to smoking for 50 years at 10 CPD (25 pack-years), the estimated excess relative risks ranged from 21.9 for Native Hawaiians to 8.0 for Latinos over the five groups. A lower risk among Japanese Americans and higher risk among African Americans, compared to whites, was not seen after adjusting for predicted total nicotine equivalents, while the prominent differences in risk between Native Hawaiians and Latinos endured.