External validation of the Paddington International Virtual Electronic ChromoendoScopy ScOre as a good endoscopic score to define mucosal healing and predict long‐term clinical outcomes in ulcerative colitis

Abstract

Objectives To define endoscopic and histological remission in ulcerative colitis (UC) accurately, several scoring systems have been established. A novel virtual electronic chromoendoscopy score, the Paddington International Virtual ChromoendoScopy ScOre (PICaSSO), was developed, validated, and reproduced to assess inflammation grade and predict patient prognosis. We externally verified and validated the clinical value of PICaSSO in UC patients. Methods This prospective study enrolled 63 UC patients. The Mayo endoscopic score (MES), UC Endoscopic Index of Severity (UCEIS), and PICaSSO were adopted for endoscopic evaluation. All biopsy samples were scored using the Robarts histological index (RHI), Nancy histological index (NHI), and “Extent, Chronicity, Activity, Plus additional findings” (ECAP) score. Patients with an endoscopic MES of 0–1 at baseline were followed up during a median time of 23.5 months. Results PICaSSO was strongly correlated with other endoscopic and histological scoring systems. PICaSSO ≤3 had advantages in assessing histological remission (HR), with the highest accuracy of 88.9% for ECAP‐HR. Relapse‐free survival rates were significantly different between patients with MES 0 and MES 1 and patients with PICaSSO ≤3 and >3 (P = 0.010 and 0.018, respectively). Conclusions PICaSSO was externally validated with strong correlations with other endoscopic and histological scoring systems in UC, and PICaSSO‐ER might potentially predict a better long‐term clinical outcome in UC patients.

Present and future of endoscopy precision for inflammatory bowel disease

“…57 In the external validation study, a PICaSSO score ≤3 was associated with increased relapsefree survival rates than a score >3 (hazard ratio 0.189). 58 Moreover, the endoscopic remission by VCE-PICaSSO alone has been similar to combined endoscopic and HR for predicting specified clinical outcomes at 12 months in UC patients. 59 Notably, a recent work by Hayashi et al 60 evaluated the usefulness of texture and color enhancement imaging (TXI) (Olympus) in predicting UC relapse.…”

“…A large prospective real‐life international study evaluating a cohort of 307 UC patients showed that a PICaSSO score ≤3 predicted major adverse outcomes (MAOs) at 6 and 12 months better than a PICaSSO >3 (hazard ratio 0.19 and 0.22, respectively) and similarly to HR 57 . In the external validation study, a PICaSSO score ≤3 was associated with increased relapse‐free survival rates than a score >3 (hazard ratio 0.189) 58 . Moreover, the endoscopic remission by VCE‐PICaSSO alone has been similar to combined endoscopic and HR for predicting specified clinical outcomes at 12 months in UC patients 59 .…”