Screening for colorectal cancer and other GI cancers

Most of the major advances in the screening for gastrointestinal cancers this year were in the area of colorectal cancer screening. Currently, screening is recommended for the prevention of colorectal cancer in average and high-risk populations. For average risk populations, large randomized trials support the use of screening fecal occult blood testing, and case-control studies support the use of screening sigmoidoscopy. This year, several investigators have addressed issues related to the probability of identifying advanced lesions in the proximal colon following a positive screening flexible sigmoidoscopy. Similarly, two studies identified that villous histology in an index polyp was associated with an increased risk of recurrent colonic polyps. Additionally, two large trials provided new insight about the prevalence of mutations in the MLH1 or MSH2 mismatch-repair genes among patients with colorectal cancer. Lastly, a case-control study from Sweden provided the best evidence to date that surveillance colonoscopies for patients with long-standing ulcerative colitis may reduce cancer-related mortality. Although further work is needed, these studies have served to advance our knowledge of colorectal cancer screening substantially.