Application of magnifying chromoendoscopy in endoscopic mucosal resection of colorectal neoplasms

Abstract

Objective To evaluate the clinical efficacy and safety of endoscopic mucosal resection (EMR) assisted with magnifying chromoendoscopy in treatment of colorectal neoplasms. Methods Patients who met criteria for EMR including appropriate flat or depressed type and sessile lesions were enrolled. The association of morphology of colorectal lesions with histopathology was observed and the accuracy of estimation of invasive depth by magnifying chromoendoscopy was evaluated. Results Ninety lesions of 81 patients were reseeted by EMR (25 being sessile and 65 being flat or depressed). The histological results revealed low-grade dysplasia (LGD) in 58 lesions, high-grade dysplasia (HGD) in 20 lesions, and adenocarcinoma in 12 lesions. The average size of lesions was (1.4±0.5) cm in HGD, (1.6±0.5) cm in cancer and (1.0±0.4) cm in LGD with no significant difference (P> 0.05). It was shown that the flat and depressed lesions were more likely to be HGD or cancer as compared to sessile lesions, but with no statistical difference [41.5 % (27/65)vs. 20.0% (5/25), P= 0.084]. Moreover, the lesion with central depression was more likely to be HGD or cancer as compared to those without depressed surface [51.0% (25/49) vs. 17.1 % (7/41), P<0.01)]. The accuracy of estimating invasive depth by magnifying chromoendoscopy was 97.8% (86/90). Complete resection was confirmed histologically in 95.8% (88/90) of all lesions. Conclusions Colorectal lesions of depressed and flat types with central depression are more likely to be malignant. Estimation of invasive depth of colorectal neoplasia by magnifying chromoendoscopy in EMR treatment makes it more effective and safer. Key words: Colorectal neoplasms; Endoscopic mucosal resection; Magnifying chromoendoscopy