| [ Summary ] |
The work of Prof. Shin-ei Kudo and his colleagues played a major role in changing the status of colorectal IIc lesions from "illusory" to "actual" neoplastic lesions in Japan and the world at large. In the 30 years that followed, however, these lesions have remained poorly characterized. One possible reason is that while sessile serrated adenomas/polyps (SSA/Ps) or non-granular type laterally spreading tumors (LST-NGs) are readily detectable and provide material for discussion at congress meetings, colorectal IIc lesions are far less detectable and less likely to be the subject of discussion. Colorectal IIc lesions remain poorly detectable because they inherently grow slowly and undergo rapid morphological changes after achieving deep submucosal invasion, from IIa+IIc to Is+IIc to advanced cancer, while retaining morphological characteristic of IIc lesions for a brief duration in which they remain unlikely to be recognized. To improve the rate of IIc lesion detection, therefore, the number of patients who undergo initial colonoscopies needs to increase, and these examinations must be substantiated by high-quality colonoscopic observations focused on IIc lesion detection. In the near future, I expect to see the advent of an age in which novel colonoscopy devices will be made available to enable all endoscopists to easily detect IIc lesions. |