Genetic alterations in esophageal cancer and their relevance to etiology and pathogenesis: a review.

Cancer of the esophagus exists in 2 main forms with different etiological and pathological characteristics-squamous cell carcinoma (SCC) and adenocarcinoma (ADC). This review focuses on the occurrence of genetic alterations in SSC and ADC of the esophagus and on their possible implications for the elucidation of the etiology and pathogenesis of these cancers. The most common alterations found in esophageal cancers include allelic losses at chromosomes 3p, 5q, 9p, 9q, 13q, 17p, 17q and 18q, as well as mutations of p53 (mostly missense), Rb (deletions), cyclin DI (amplifications) and c-myc (amplifications). The sequence of occurrence of these alterations with respect to histopathological tumor progression is discussed. Our findings underscore the different etiology and pathogenesis of SCC vs. ADC and suggest that the genetic alterations observed may represent molecular fingerprints of critical risk involved in the development of these 2 cancers.