To determine the effect of the subjects’ cigarette smoke exposure on SULT1C2 messenger RNA (mRNA) levels, LUAD tumor samples were split based on patients’ smoke exposure status into four major TCGA-annotated categories: never smokers (category 1), former smokers who quit more than 15 years prior (category 2), former smokers who quit less than 15 years prior (category 3), and current smokers (category 4). This evidence concerns the gene SULT1C2 and neoplasm.