PPIG and pancreatic neoplasm: Although several molecular epidemiologic studies have examined the associations between variants of the genes encoding CYP, GST, and NAT enzymes and pancreatic cancer risk, most of the important findings regarding the main effects of genetic variations or gene–environment interactions were reported by 2 case–control studies: an ongoing hospital-based case–control study at MD Anderson Cancer Center21 and a population-based case–control study in 6 areas of San Francisco Bay from 1994 to 20018 (Table 1).