Colitis associated dysplasia in IBD
- Dysplasia can be flat or form a mass (dysplasia-associated lesion or mass [DALM]). Dysplasia in UC is graded as negative, indefinite, low grade, or high grade.
- The differential diagnosis of DALM is sporadic adenoma.
- The distinction between the two is difficult and requires clear communication between the pathologist and the endoscopist.
- If the lesion is isolated from the areas affected by colitis, then the diagnosis is usually a sporadic adenoma.
- A DALM lesion shows foci of dysplastic epithelium associated with areas of colitis. The pattern of dysplasia may not be uniform.
- Positive staining with beta-catenin may help in these cases that are negative for p53.
- Both DALM of any grade and flat, high-grade dysplasias are associated with the increased risk of invasive adenocarcinomas; total colectomy is usually recommended in UC cases.
