Age at lung cancer diagnosis in females versus males who never smoke by race and ethnicity

Abstract

Background: We characterized age at diagnosis and estimated sex differences for lung cancer and its histological subtypes among individuals who never smoke. Methods: We analyzed the distribution of age at lung cancer diagnosis in 33,793 individuals across 8 cohort studies and two national registries from East Asia, the United States (US) and the United Kingdom (UK). Student’s t-tests were used to assess the study population differences (Δ years) in age at diagnosis comparing females and males who never smoke across subgroups defined by race/ethnicity, geographic location, and histological subtypes. Results: We found that among Chinese individuals diagnosed with lung cancer who never smoke, females were diagnosed with lung cancer younger than males in the Taiwan Cancer Registry (n = 29,832) (Δ years = −2.2 (95% confidence interval (CI):−2.5, −1.9), in Shanghai (n = 1049) (Δ years = −1.6 (95% CI:-2.9, −0.3), and in Sutter Health and Kaiser Permanente Hawaiʽi in the US (n = 82) (Δ years = −11.3 (95% CI: −17.7, −4.9). While there was a suggestion of similar patterns in African American and non-Hispanic White individuals. the estimated differences were not consistent across studies and were not statistically significant. Conclusions: We found evidence of sex differences for age at lung cancer diagnosis among individuals who never smoke.