The case for surveillance in ulcerative colitis

Patients with ulcerative colitis are at increased risk over an unaffected population for developing colorectal cancer. For more than 20 years, surveillance programs throughout the world have studied high-risk patients by offering colonoscopy with extensive biopsy and colectomy for the detection of high grade dysplasia or asymptomatic cancer. In general, surveillance programs have failed to document a decreased cancer-related mortality compared to what would be expected. Since cancer surveillance in ulcerative colitis patients is now the 'standard of care' it cannot be abandoned as being ineffective. Alternative strategies need to be tested to increase effectiveness. One way to improve effectiveness of cancer surveillance is to identify alternative markers of malignancy that would complement dysplasia. Such an ideal marker may be expected to increase the number of cancer deaths prevented without inordinately increasing the number of unnecessary colectomies performed. Of the candidate alternative markers of malignancy - global DNA demethylation, DNA aneuploidy, suppressor gene mutations and loss of heterozygosity, oncogene mutations and abnormal mucin production - certain suppressor gene mutations (p53 in particular) offer the most promise as being the most effective at a reasonable cost.