Kudo's pit pattern classification for in vivo optical diagnosis and discrimination of advanced colorectal polyps

Colonoscopy is currently the basic diagnostic tool for the large intestine. The size of lesions assessed during the investigation is one criterion for assessing the risk of polyps transforming into colorectal cancer. The techno-logical development of endoscopes and the possibility of direct assessment of lesion's surface during the endoscopic examination and to use appropriate treatment. The aim of this study is to analyze the consistency between the histopathological assessment of high-risk lesions in colonoscopy and the determination according to Kudo's pit pattern classification.

The analysis included the results of colonoscopies performed over a 2-year period, in which polyps were diagnosed endoscopically and either polypectomies were performed, or sections were taken from these polyps and a pit pattern analysis was done according to Kudo's classification.

A total of 1038 patients (age, 67.2 ± 12.7 years) were enrolled in the study. Of the 1981 samples taken in total, polyps larger than 1 cm were found in 96 cases, laterally spreading tumors (LSTs) were found in 48 cases, and macroscopic infiltration or tumors were found in 110 cases. The results of the histopathological examination were obtained in 248 cases. A value of 4 or higher in the Kudo classification turned out to be the best parameter to differentiate malignant lesions from benign ones for lesions larger than 1 cm and laterally spreading tumors, with a sensitivity of 91.2% and a specificity of 70.4%.

The assessment of polyps according to Kudo's classification is a useful tool for assessing the malignancy of lesions as part of a routine colonoscopy.