Endoscopic diagnosis of colorectal serrated lesions: Current status and future perspectives based on the results of a questionnaire survey

Serrated lesions, especially sessile serrated adenoma/polyps (SSA/P) are considered one of the most important precursors of colorectal cancers. However, it is still difficult to endoscopically differentiate SSA/P from hyperplastic polyps. In the present review, we mainly focus on the current status and future perspectives of endoscopic diagnosis of colorectal serrated lesions based on the results of a questionnaire survey and report from the Endoscopic Forum Japan (EFJ) 2015 held in Tokyo in August 2015. The proposed diagnostic strategy recommended for colorectal serrated lesions is as follows. (i) For detection, use of an updated image-enhanced endoscopy system including autofluorescence imaging (AFI) and narrow-band imaging (NBI) may be promising. (ii) For differential diagnosis (hyperplastic polyp or SSA/P) of diminutive, small and large serrated lesions, NBI with magnification and magnifying chromoendoscopy using both indigocarmine and crystal violet should be applied, respectively. (iii) For differential diagnosis of SSA/P (with or without cytological dysplasia), magnifying chromoendoscopy, endocytoscopy and updated AFI system modalities might be promising.