A Quantitative MRCP-derived Score for Medium-Term Outcome Prediction in Primary Sclerosing Cholangitis.

Background: Magnetic resonance cholangiopancreatography (MRCP) is the gold standard for diagnosis of patients with primary sclerosing cholangitis (PSC). The semi-quantitative MRCP-derived Anali scores proposed for risk stratification, have poor-to-moderate inter-reader agreement. Aims: To evaluate the prognostic performance of quantitative MRCP metrics in PSC. Methods: This is a retrospective study of PSC patients undergoing MRCP. Images were processed using MRCP + software (Perspectum Ltd, Oxford) that provides quantitative biliary features, semi-automatically extracted by artificial intelligence-driven analysis of MRCP-3D images. The prognostic value of biliary fea-tures has been assessed for all hepato-biliary complications. Results: 87 PSC patients have been included in the analysis. Median follow-up from MRCP to event/censoring of 30.9 months (Q1-Q3 = 13.6-46.6). An adverse outcome occurred in 27 (31.0%) patients. The number of biliary strictures (HR = 1.05 per unit, 95%CI 1.02-1.08, p < 0.0 0 01), spleen length (HR = 1.16 per cm, 95%CI 1.01-1.34, p = 0.039), adjusted for height, age at MRCP, and time from diagnosis to MRCP predicted higher risk of hepatobiliary complications. These were incorporated into a the quantitative MRCP-derived PSC (qMRCP-PSC) score (C-statistic = 0.80). After 3-fold cross-validation, qMRCP-PSC out-performed the Anali score in our cohort (C-statistic of 0.78 vs 0.64) and enabled the discrimination of survival of PSC patients (log-rank p < 0.0 0 01).Conclusions: The qMRCP-PSC score identified patients at higher risk of hepatobiliary complications and outperformed the available radiological scores. It represents a novel quantitative biomarker for disease monitoring and a potential surrogate endpoint for clinical trials. (c) 2022 The Author(s). Published by Elsevier Ltd on behalf of Editrice Gastroenterologica Italiana S.r.l. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )