Nomogram Development and Validation to Predict Hepatocellular Carcinoma Tumor Behavior by Preoperative Gadoxetic Acid-Enhanced MRI

Abstract

Background: Pretreatment evaluation of tumor biology and microenvironment of hepatocellular carcinoma (HCC) are important to predict prognosis and plan treatment. We aimed to develop nomograms based on Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) to predict microvascular invasion (MVI), tumor differentiation, and immunoscore. Methods: This retrospective study included 273 patients with HCC who underwent preoperative Gd-EOB-DTPA-enhanced MRI. Patients were assigned to two groups: training (N = 191) and validation (N = 82). Univariable and multivariable logistic regression analyses were performed to investigate clinical variables and MRI features' associations with MVI, tumor differentiation and immunoscore. Nomograms were developed based on features associated with these histopathological features in the same training cohort, then validated, and evaluated. Findings: Predictors of MVI included tumor size (P = 0.002), rim enhancement (P = 0.017), percent reduction in T1 images (T1D%; P = 0.043), and standard deviation of apparent diffusion coefficient (P = 0.028), while capsule (P = 0.007), mean relaxation time on the hepatocellular phase (T1E; P < 0.001), and alpha-fetoprotein levels (P = 0.003) predicted tumor differentiation. Predictors of immunoscore included the radiologic score (P = 0.001) constructed by tumor number, intratumoral vessel, margin, capsule, rim enhancement, T1D%, relaxation time on plain scan (T1P) and T1E, and serum alpha-fetoprotein (P = 0.027) and alanine aminotransferase levels (P = 0.028). Three nomograms achieved high C-index in predicting MVI (0.754, 0.746), tumor differentiation (0.758, 0.699) and immunoscore (0.737, 0.726) in the training and validation cohorts, respectively. Interpretation:MRI-based nomograms effectively predict tumor behaviors in HCC and may assist clinicians in prognosis prediction. Funding: This work was funded by the National Natural Science Foundation of China (No. 81771908, 81571750, 81801703), the National Science Fund for Distinguished Young Scholars (No. 81825013) and the Guangdong Natural Science Foundation of Guangdong Province (No. 2018A030310282). Declaration of Interest: The authors declare that they have no competing interests. Ethical Approval: The Institutional Ethic Review Board has approved our study, and informed consent was waived due to the retrospective nature of the study.