Classification and Significance of Serrated Colorectal Polyps in Inflammatory Bowel Disease
Huaibin M Ko, Noam Harpaz, Alexandros D Polydorides. Mount Sinai School of Medicine, New York, NY
Background: Serrated colorectal polyps (SCPs) encompass pathologically distinct entities with different prognostic and management implications, but the significance of corresponding polyps in patients with IBD has not been thoroughly studied.
Design: We retrospectively identified 78 patients (47 male, 31 female, mean age 55.9 y) with longstanding ulcerative, Crohn, or indeterminate colitis (N=56, 19 and 3, respectively) who were diagnosed at surveillance colonoscopy with SCPs other than conventional hyperplastic polyps (HPs). Slides of the index SCPs were evaluated by 2 pathologists and classified as follows: (A) sessile serrated adenoma/polyp (SSA/P)-like (negative for cytologic dysplasia), (B) traditional serrated adenoma (TSA)-like (positive for low-grade dysplasia), and (C) cytologically atypical HP-like (indefinite for dysplasia). The patients' pathology results from all prior and subsequent surveillance examinations were reviewed and the presence of any synchronous or metachronous dysplasia (exclusive of sporadic adenomas) or carcinoma was recorded.
Results: We identified 29 patients with type A, 30 type B, and 19 type C SCPs (Table). Compared to type B and C SCPs, type A SCPs predominated in females (62% vs. 30% and 21%, respectively, p=0.007) and were more frequently right-sided (59% vs. 23% and 21%, respectively, p=0.006). None of the 29 patients with only type A SCPs was diagnosed with synchronous or metachronous dysplasia over a mean duration of 91.0 months and mean 6.3 examinations per patient, compared with 23 of 30 (77%) and 10 of 19 (53%) patients with type B and C SCPs, respectively (p=1x10-8), evaluated over statistically comparable intervals and numbers of examinations. Type B and C SCPs were associated with 21 low-grade dysplasias, 7 high-grade dysplasias, and 5 invasive adenocarcinomas.
|SCP (N)||Surveillance (mean, mo)||Exams (mean, #)||Age (mean, y)||Sex (M:F)||IBD (UC:CD:IC)||Site (R:L)||Neoplasia|
|Type A (29)||91.0||6.3||53.2||11:18||19:9:1||17:12||0/29|
|Type B (30)||83.6||8.3||58.4||21:9||22:6:2||7:23||23/30|
|Type C (19)||102.2||9.1||56.1||15:4||15:4:0||4:15||10/19|