Objectives: Serrated polyps of the colorectum are a histologically and genetically heterogeneous group of lesions, which include classic hyperplasic polyps, sessile serrated adenomas (SSAs), and traditional serrated adenomas. Accumulating evidence suggests that they may have different malignancy potentials. This study sought to determine the association between the presence of large serrated colorectal polyps and synchronous advanced colorectal neoplasia.
Methods: Among 4,714 asymptomatic subjects who underwent screening colonoscopy, cases of advanced colorectal neoplasia (tubular adenoma > or =1 cm, adenoma with any villous histology, adenoma with carcinoma in situ / high-grade dysplasia, or invasive adenocarcinoma) were compared with controls without advanced neoplasia with respect to candidate predictors, including age, sex, family history of colorectal cancer, body mass index, the presence and number of small tubular adenomas (<1 cm), the presence of multiple small serrated polyps (<1 cm), and the presence of large serrated polyps (> or =1 cm). Independent predictors of advanced neoplasia were determined by multivariate logistic regression analysis.
Results: Among 467 cases and 4,247 controls, independent predictors of advanced colorectal neoplasia were increasing age (odds ratio (OR)=4.51; 95% confidence interval (CI), 1.43-14.3; P=0.01 for subjects > or =80 years vs. 50-54 years of age); non-advanced tubular adenomas (OR=2.33; 95% CI 1.37-3.96, P=0.0017 for 3 or more); and large serrated polyps (OR=3.24; 95% CI 2.05-5.13, P<0.0001). In total, 109 subjects (2.3% of the study population) had large serrated polyps. Right- and left-sided large serrated polyps had a similar association with advanced colorectal neoplasia (OR=3.38 vs. 2.66, P=0.62).
Conclusions: Large serrated polyps are strongly and independently associated with synchronous advanced colorectal neoplasia. Our results suggest that large serrated polyps may be a marker for advanced colorectal neoplasia. Further studies are needed to determine whether the association with advanced neoplasia differs among subsets of serrated polyps, particularly SSAs and classic hyperplastic polyps.