Synchronous occurrence of different polyp types during colonoscopy

Summary Background and Aims The general probabilities of finding different types of hyperplastic or neoplastic colon lesions clustering in the same patient are unknown. We hypothesised that a systematic analysis of polyp clustering would reveal a high frequency of different concurrent types and that such clustering would be influenced by the underlying histopathology of the individual polyps. Methods Using an electronic database of histopathologic records, a cross‐sectional study of 2,910,174 colonoscopies evaluated the concordant occurrence of hyperplastic and neoplastic mucosal lesions. Results Amongst patients harbouring any colon polyp, one can expect to find another histopathologic type in about 22%. Being the most prevalent type of polyp, tubular adenoma was the most common type of colonic polyp to be associated with other lesions. For instance, 31% of all colonoscopies with sessile serrated adenomas or hyperplastic polyps also revealed tubular adenomas. Hyperplastic polyp, the second most prevalent type of colonic polyp, was also the second most common type of polyp to be found associated with other types of neoplasia. For instance, 25% of all colonoscopies with sessile serrated adenomas and 31% of those with tubular adenomas also revealed hyperplastic polyps. Conclusions Different types of colon polyps commonly coincide in individual patients. The present set of data from a large nationwide database may provide guidance for the endoscopist of what variety in colon polyps to expect during colonoscopy.