Issues

In the foreground are photographic images of clinical Barrett’s esophagus (BE; top; photo courtesy of Brian J. Reid, M.D., Ph.D.) and of the histology of Barrett’s esophagus (bottom; image courtesy of Elizabeth Montgomery, M.D.). BE involves early genome-wide chromosomal deletions that progress and increase in size with increasing histopathological severity; the number of larger copy losses is significantly higher in advanced BE and esophageal adenocarcinoma compared with that in early BE lesions. See articles by Wistuba and Meyerson (beginning on page 404 and Li et al. (beginning on page 413) for more information. The background image is an Illumina BeadChip scan depicting sequence variations in several microRNA-related genes. Genetic variations within microRNAs and their processing pathways are important to esophageal cancer risk, which dramatically increases with an increasing number of variants. Genetic variants in the normal esophagus progress through microRNA pathway changes to esophageal adenocarcinoma, presumably progressing through Barrett’s esophagus prior to cancer. These findings may lead to the development of tools for identifying high-risk patients and ultimately to better prevention. See article by Ye et al. (beginning on page 460) for more information.