LI‐RADS Category on MRI Is Associated With Recurrence of Intrahepatic Cholangiocarcinoma After Surgery: A Multicenter Study

The Liver Imaging Reporting and Data System (LI-RADS) is a comprehensive system for standardizing the terminology and interpretation of liver imaging. The association between the LI-RADS category and tumor recurrence in patients with intrahepatic cholangiocarcinomas (iCCAs) has not yet been evaluated in a multicenter study.To retrospectively investigate the preoperative clinical and imaging features associated with recurrence-free survival (RFS) after curative resection of iCCAs and to identify the role of the LI-RADS category in at-risk patients.Retrospective, multicenter.A total of 113 patients (mean age: 61.1 years; 74 men, 39 women) who underwent preoperative contrast-enhanced MRI and curative surgical resection for a single treatment-naive iCCA between 2008 and 2021.A 3 T dual gradient-echo T1 WI with in- and opposed-phase, turbo spin-echo T2 WI, diffusion-weighted echo-planar images, and three-dimensional gradient-echo T1 WI before and after administration of contrast agent.MR imaging features were evaluated and assigned for each lesion using LI-RADS version 2018. RFS was calculated from the date of surgery to tumor recurrence or the last imaging date without evidence of recurrence. Factors affecting RFS were evaluated using clinical and imaging features.Cox proportional hazards model, Kaplan-Meier method, and log-rank test. A P-value of <0.05 was considered statistically significant.A total of 93 (82.3%) were categorized as LR-M and 20 (17.7%) were categorized as LR-4 or 5. In the multivariable analysis, LR-M category (hazard ratio [HR], 8.035; 95% confidence interval [CI], 1.096-58.931) and a tumor size >3 cm on MRI (HR, 2.690; 95% CI, 1.319-5.487) were independent factors for poor RFS. The 5-year RFS rate was significantly higher in patients with iCCA categorized as LR-4 or 5 than in those categorized as LR-M (94.4% vs. 51.9%, respectively).Patients with iCCA categorized as LR-4 or 5 may have a better RFS than those categorized as LR-M.3 TECHNICAL EFFICACY: Stage 2.