HD-WLE COLONOSCOPY AND CHROMOENDOSCOPY IN THE DETECTION OF DYSPLASIA IN LONG-STANDING ULCERATIVE COLITIS

Aims Improving approaches to the endoscopic diagnosis of ulcerative colitis (UC)-associated dysplasia includes improvement in the detection of dysplasia and labour intensity reduction of the diagnosis process. In this regard, the study aimed to determine the effectiveness of HD-WLE colonoscopy and chromoendoscopy in the detection of dysplasia in long-standing UC.

Methods A single-centre prospective study (November 2017-June 2019) involving 140 treated patients with an average duration of UC about 16 years (8–44) conducted. All patients underwent HD-WLE colonoscopy, chromoendoscopy (indigo carmine), targeted biopsy, the subsequent histological study. We analyzed the endoscopic data (Paris classification, SCENIC, Kudo’s pit pattern), and the histological data (Ridell’s classification), evaluated the effectiveness of endoscopic diagnostic.

Results HD-WLE colonoscopy revealed dysplasia in 27 patients (19.29%): 20 (74.07%) −1 lesion, 7 (25.93%) – 2 lesions. A total of 34 lesions with sings of dysplasia were detected. Concomitant colon cancer diagnosed in 2 (7.41%) cases. Chromoendoscopy verified dysplasia in the same 34 cases. The histological examination revealed: low-grade dysplasia in 20 (58.82%) cases, indefinite for dysplasia – 7 (20.59%), sporadic adenomas – 7 (20.59%), and there were no cases of high-grade dysplasia. In 2 (100%) cases colon cancer was confirmed (adenocarcinoma). Cases of histologically indefinite for dysplasia were excluded from further analysis. Comparative analysis showed the same rate of true-positive and false-positive results for both HD-WLE colonoscopy and сhromoendoscopy, and the effectiveness of both methods in the detection of dysplasia was amount to 74%.

Conclusions Our study shows similar effectiveness for HD-WLE colonoscopy and chromoendoscopy in detection of dysplasia in long-standing UC. So, in choosing an approach for endoscopic diagnosis of long-standing UC-associated dysplasia, preference may give to the reduction in the time of endoscopic examination with HD-WLE colonoscopy. Therefore, we emphasize the need to continue research aimed at improving the labour-intensive endoscopic process of identifying UC-associated dysplasia.