Multi-centre derivation and validation of a colitis-associated cancer risk prediction web-tool
Curtius K., Kabir M., Al Bakir I., Choi C-HR., Hartono J., Johnson M., East JE., Lindsay JO., Vega R., Thomas-Gibson S., Wilson A., Graham TA., Hart A.
<jats:p><jats:bold>Background and Aims</jats:bold> Ulcerative colitis (UC) patients diagnosed with low-grade dysplasia (LGD) have increased risk of developing advanced neoplasia (AN; high-grade dysplasia or colorectal cancer). We aimed to develop and validate a predictor of AN risk in UC patients with LGD and create a visual web-tool to effectively communicate the risk. <jats:bold>Methods</jats:bold> In our retrospective multi-centre validated cohort study, adult UC patients with an index diagnosis of LGD, identified from four UK centres between 2001-2019, were followed until progression to AN. In the discovery cohort (n=248), a multivariate risk prediction model was derived from clinicopathological features using Cox regression. Validation used data from 3 external centres (n=201). The validated model was embedded in a web-based tool to calculate and illustrate patient-specific risk. <jats:bold>Results</jats:bold> Four endoscopic variables were significantly associated with future AN progression in the discovery cohort: endoscopically visible LGD > 1 cm (HR = 2.8; 95% CI 1.3-6.0), incomplete endoscopic resection (HR = 2.9; 95% CI 1.3-6.5), moderate/severe histological inflammation within 5 years of LGD diagnosis (HR = 3.0; 95% CI 1.3-6.7), and multifocality (HR = 2.8; 95% CI 1.3-6.1). In the validation cohort, this 4-variable model accurately predicted future AN cases with overall calibration Observed/Expected = 1 (95% CI 0.63-1.5), and achieved perfect specificity for the lowest predicted risk group over 13 years of follow-up. <jats:bold>Conclusion</jats:bold> Multi-cohort validation confirms that patients with large, unresected, and multifocal LGD and recent moderate/severe inflammation are at the highest risk of developing AN. Personalised risk prediction provided via the Ulcerative Colitis-Cancer Risk Estimator web-tool (www.UC-CaRE.uk) can be used to support treatment decision-making.</jats:p>