Hereditary nonpolyposis colorectal cancer (Lynch syndromes I and II): a common genotype linked to oncogenes?

We hypothesize that: hereditary nonpolyposis colorectal cancer (HNPCC) accounts for a significant proportion of the colon cancer burden; the premalignant colonic mucosa in HNPCC patients may be comparable in many respects to the premalignant polyps in its hereditary multiple adenomatous polyposis counterpart; and finally, study of HNPCC colonic mucosa may harbor important clues for elucidation of the multistep process of carcinogenesis, including relationships between activated oncogenes, genetics, and environmental perturbations.