Chromoendoscopy and high-magnification colonoscopy in early detection of colorectal cancer.

Flat and depressed lesions in the colons are difficult to detect with conventional colonoscopic techniques, and chromoendoscopy with high magnification has consequently gained wide application for early detection of colorectal cancer and its precursors. These techniques allow targeted in vivo luminal treatments and make possible earlier and more accurate diagnosis on the basis of pit pattern classification as proposed by Kudo Sinei. According to studies conducted by Japanese researchers, magnification chromoendoscopy can be used to assess the histology and invasive depth of the cancer, and thus help in the detection of flat and depressed colonic lesions and the subsequent surgical treatment of these lesions by way of endoscopic mucosal resection (EMR) or endoscopic piecemeal mucosal resection (EPMR). Due attention should be given to the clinical significance of high-magnification chromoendoscopy in the identification of the lesions.