2018 Volume 93 Issue 1 Pages 128-130
A 79-year-old man was referred to our hospital for further examination of a colorectal cancer. Colonoendoscopy revealed a 0-Is type lesion of 18mm in diameter in the rectosigmoid colon, showing redness on conventional images. In magnified images, the lesion showed JNET type 3 findings on narrow band imaging (NBI) and a VI high-grade pit pattern on chromoendoscopy after crystal violet staining. We diagnosed the lesion as submucosal massively invasive cancer and surgical resection with D2 lymph node dissection was performed. Histological examination revealed well to moderately differentiated tubular adenocarcinoma with invasion into veins of the subserosa. Although advanced colorectal cancers of less than 20mm in diameter are relatively rare, we should keep in mind the difficulty of diagnosis of depth invasion of such protruded cancers.
