Dietary patterns in young lung cancer: mutation-specific environmental associations

Following peak tobacco incidence in the mid-1980's there has been a large reduction in lung cancer incidence among men that has not been seen among women. Lung cancer at a young age is now more common among women than men, reversing a decades long pattern. We sought to characterize environmental exposures among young lung cancer patients to understand potential drivers of this change in the epidemiologic profile of young lung cancer patients. We analyzed 187 patients (157 females, 84%) from the Epidemiology of Young Lung Cancer (YLC) study (ClinicalTrials.gov identifier: NCT04640259) using mutation-based grouping by shared biological mechanisms: EGFR Pathway (EGFR+ERBB2), Fusion Positive (ALK+ROS1+RET+NTRK), and Other/Mixed Mutations (including MET exon 14 skipping, TP53, KRAS, BRAF, and additional alterations). Of these, 166 patients (138 females, 83.1%) completed validated food frequency questionnaires. Dietary quality was assessed using the Healthy Eating Index-2015 (HEI-2015) and compared to U.S. reference values from NHANES. Dietary categories with elevated contaminant residue potential were identified using published literature. Statistical comparisons employed one-sample t-tests against reference means and chi-square tests for categorical variables. The EGFR groups and ALK groups had tobacco use history in 32.8% and 13.4% of patients respectively. All groups had similarly high levels of oral contraceptive exposure among women (75-100%). Dietary analysis revealed that EGFR Pathway, Fusion Positive, and Other/Mixed Mutations patients demonstrated HEI-2015 scores (out of 100) of 64.9 ± 10.7, 65.5 ± 9.8, and 63.5 ± 9.5 respectively, compared with the US reference of 58. YLC women demonstrated higher dietary quality scores than men (65.6 ± 9.7 vs. 61.8 ± 11.3), both exceeded U.S. reference values of 60 for females and 56 for males. These YLC patients also consumed more foods from dietary categories associated with elevated contaminant exposure potential, as reflected by higher HEI-2015 component scores (out of 5) for total vegetables (4.2 vs. 3.5), fruits (3.3 vs. 2.5), and whole grains (3.9 vs. 2.6). YLC patients have a diet pattern of higher diet quality, with higher exposure to whole fruits, vegetables and whole grains. While these food groups are presumed to have good health benefits, there is an emerging, under-appreciated literature that produce based whole foods often contain high pesticide/herbicide contaminants. Further investigation of the role of pesticide contaminated fruits/vegetables/whole grains is timely to assess its role, if any, in the changing lung cancer prevalence over the last 4 decades.