Dysplasia in Ulcerative Colitis
Introduction: The incidence of colorectal cancer is increased in patients with inflammatory bowel disease (IBD). Malignant transformation is seen in 2% of cases. Risk Factors: The risk of dysplasia/carcinoma in IBD is associated with several factors. 1) Duration of the disease: Patients with early disease onset are at a greater risk of malignant transformation. The risk increases rapidly 7-10 after the initial diagnosis. 2) Extent of the disease: Patients with pancolitis are at greater risk than those with more limited involvement. 3) Patients with coexistent primary sclerosing cholangitis are at a higher risk as well. 4) Type of inflammatory response: The greater the extent of acute inflammatory response, greater the risk of developing malignancy. Surveillance for Malignancy in Ulcerative Colitis: Surveillance colonoscopy to detect dysplasia/carcinoma is usually initiated 8 years after the diagnosis of UC. If a patient with UC has coexistent primary sclerosing cholangitis, they are enrolled in surveillance programs at the time of diagnosis due to higher risk of developing cancer. Surveillance is done every 1-2 years and ideally done when the disease is inactive. This colonoscopic image shows a transverse colon polyp that was discovered in a 55-year old man who was under surveillance due to a 15-year history of ulcerative colitis. A biopsy showed it to be a tubular adenoma with low-grade dysplasia. Image courtesy of: Bjorn Rembacken, MD; used with permission.