Value of green sign and chicken skin aspects for detecting malignancy of colorectal neoplasia in a prospective characterization study.

Abstract

Background and study aim: Accurate endoscopic characterization of colorectal lesions is essential for predicting histology but is difficult even for experts. Simple criteria could help endoscopists to detect and predict malignancy. The aim of this study was to evaluate the value of the green sign and chicken skin aspects in the detection of malignant colorectal neoplasia. Patients and methods: We prospectively characterized and evaluated the histology of all consecutive colorectal lesions detected during screening or referred for endoscopic resection (Pro-CONECCT study). We evaluated the diagnostic accuracy of the green sign and chicken skin aspects for the detection of superficial and deep invasive lesions. Results: 461 patients with 803 colorectal lesions were included. The green sign had a negative predictive value of 89.6% [95% CI: 87.1-91.8%] and 98.1% [95% CI: 96.7-99.0%] for superficial and deep invasive lesions, respectively. In contrast to chicken skin, the green sign showed additional value for the detection of both lesion types compared with the CONECCT classification and chicken skin (adjusted OR for superficial lesions: 5.9 [95% CI: 3.4-10.2], p<0.001, adjusted OR for deep lesions: 9.0 [95% CI: 3.9-21.1], p<0.001). Conclusions: The green sign may be associated with malignant colorectal neoplasia. Targeting these areas before precise analysis of the lesion could be a way of improving the detection of focal malignancies and the prediction of the most severe histology.