Abstract
Background and study aims Ulcerative colitis (UC) and Crohn’s disease (CD) have higher risk of colorectal cancer
(CRC). Guidelines recommend dysplasia surveillance with dye-spraying chromoendoscopy
(DCE). The aim of this systematic review and meta-analysis was to review all randomized
clinical trials (RCTs) available and compare the efficacy of different endoscopic
methods of surveillance for dysplasia in patients with UC and CD.
Methods Databases searched were Medline, EMBASE, Cochrane and SCIELO/LILACS. It was estimated
the risk difference (RD) for dichotomous outcomes (number of patients diagnosed with
one or more dysplastic lesions, total number of dysplastic lesions diagnosed and number
of dysplastic lesions detected by targeted biopsies) and mean difference for continuous
outcomes (procedure time).
Results This study included 17 RCTs totaling 2,457 patients. There was superiority of DCE
when compared to standard-definiton white light endoscopy (SD-WLE). When compared
with high-definition (HD) WLE, no difference was observed in all outcomes (number
of patients with dysplasia (RD 0.06; 95 % CI [–0.01, 0.13])). Comparing other techniques,
no difference was observed between DCE and virtual chromoendoscopy (VCE – including
narrow-band imaging [NBI], i-SCAN and flexible spectral imaging color enhancement),
in all outcomes except procedure time (mean difference, 6.33 min; 95 % CI, 1.29, 11.33).
DCE required a significantly longer procedure time compared with WLE (mean difference,
7.81 min; 95 % CI, 2.76, 12.86).
Conclusions We found that dye-spraying chromoendoscopy detected more patients and dysplastic lesions
than SD-WLE. Although no difference was observed between DCE and HD-WLE or narrow-band
imaging, the main outcomes favored numerically dye-spraying chromoendoscopy, except
procedure time. Regarding i-SCAN, FICE and auto-fluorescence imaging, there is still
not enough evidence to support or not their recommendation.
