Prognostic Implications of CT- and MRI-Based LI-RADS Category M Features in Intrahepatic Cholangiocarcinoma: An
Yong Jun Jung1, Eun Sun Choi1, Dong Hwan Kim2
1Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Republic of Korea.
Objective:
Liver Imaging Reporting and Data System category M (LR-M) is associated with a poor prognosis in intrahepatic cholangiocarcinoma (iCCA). However, the prognostic value of individual LR-M features across imaging modalities remains unclear. We aimed to determine, through intraindividual comparisons, whether the prognostic value of individual LR-M features differs between CT and MRI in patients with iCCA at risk for hepatocellular carcinoma.
Materials And Methods:
This retrospective study included consecutive patients with cirrhosis or chronic hepatitis B who underwent curative-intent resection for iCCA and preoperative multiphasic CT and MRI between 2010 and 2019. CT and MRI images were reviewed in separate sessions ≥4 weeks apart. Cox proportional hazards regression analyses with and without adjustment for LI-RADS categorization (non-LR-M vs. single-modality LR-M or dual-modality LR-M) were performed to evaluate the associations of CT- and MRI-based targetoid and non-targetoid LR-M features and other variables with recurrence-free survival (RFS) and overall survival (OS).
Results:
A cohort of 122 patients (mean age, 57.9 ± 10.4 years) was included. MRI demonstrated significantly higher frequencies than CT for targetoid (84.4% vs. 73.8%, P = 0.007) and non-targetoid features (43.4% vs. 20.5%, P < 0.001), resulting in a higher rate of LR-M categorization (90.2% vs. 81.1%, P = 0.003). In the multivariable analysis, CT-based targetoid features (hazard ratio [HR] = 2.31 for RFS, P = 0.010; HR = 1.85 for OS, P = 0.043) and MRI-based non-targetoid features (HR = 2.15 for RFS, P = 0.005; HR = 2.09 for OS, P = 0.008) were independently associated with poorer survival. After adjustment for LI-RADS categorization, MRI-based non-targetoid features remained independently associated with poorer RFS (HR = 1.76, P = 0.041) and OS (HR = 1.79, P = 0.038). Dual-modality LR-M designation was independently associated with poorer RFS (HR = 8.02, P = 0.042).
Conclusion:
The prognostic implications of LR-M features in iCCA vary by imaging modality and feature type. CT-based targetoid and MRI-based non-targetoid features were associated with poorer survival, and the associations between MRI-based non-targetoid features and survival remained significant after adjustment for LI-RADS categorization.
