Dysplasia in Pediatric Patients with Inflammatory Bowel Disease Shows Distinct Clinicopathologic Features Compared to that in Adult Patients.

Abstract

Due to its rarity, there is limited information on the clinicopathologic features of dysplasia in pediatric patients with inflammatory bowel disease (IBD). The existing surveillance guidelines for these patients do not include dysplasia as a potential risk factor for colorectal cancer (CRC), and there is no clear guidance on the optimal strategy for detecting dysplasia. As such, we analyzed the clinicopathologic features of 20 IBD patients who developed at least one instance of dysplasia (n = 56) before the age of 21 years. The results were then compared with data from a previously published adult cohort, which included 315 dysplastic lesions from 167 consecutive adult IBD patients. The study group consisted of 11 males and 9 females, with a mean age of 11 years at the time of IBD diagnosis. The mean age at the time of the first dysplasia diagnosis was 18 years for the study group compared to 54 years for the adult group. The study group had a lower incidence of ulcerative colitis (65% vs. 92% in the adult group, p < 0.001), but the proportion of patients with concurrent primary sclerosing cholangitis (PSC) was nearly double that of the adult group (25% vs. 13%, p = 0.129). Dysplasia in the study group was more likely to be nonconventional (38%, p = 0.047) and invisible or flat (50%, p < 0.001) compared to the adult group (25% and 24%, respectively). High-risk nonconventional dysplastic subtypes, including crypt dysplasia (13%, p = 0.016), goblet cell-deficient dysplasia (11%, p = 0.010), and hypermucinous dysplasia (9%, p = 0.009), were more common in the study group compared to the adult group (4%, 3%, and 2%, respectively). The mean duration from IBD diagnosis to the first dysplasia diagnosis was significantly shorter in the study group (8 years) than in the adult group (16 years) (p = 0.005). While dysplastic lesions in the adult group were more likely to present as high-grade dysplasia (HGD) at initial diagnosis (17% vs. 4% in the study group, p = 0.008), the rate of advanced neoplasia (HGD or CRC) on follow-up was similar between the two groups (26% in the adult group vs. 22% in the study group, p = 1.000). In conclusion, dysplasia in pediatric IBD patients is often associated with nonconventional features (including the high-risk subtypes), an invisible/flat appearance, concurrent PSC, and early development (within 8 years of IBD diagnosis).