The establishment and application of a preoperative predictive nomogram for hepatocellular carcinoma with microvascular invasion

Objective To establish a preoperative nomogram model in predicting microvascular invasion (MVI) and to test its predictive effectiveness in hepatocellular carcinoma (HCC). Methods This retrospective study was conducted on 798 patients with HCC, including 690 males and 108 females, aged (49.8±10.9) years old who underwent curative hepatectomy in the Guangxi Medical University Affiliated Tumor Hospital between January 2014 and December 2017 were retrospectively analyzed. The patients were divided into the model group (n=579) and the validation group (n=219) according to the periods of the operation time. Independent risk factors of MVI were identified by univariate and multivariate logistic regression analysis in the model group, and a nomogram model was established according to the independent risk factors. The accuracy of the nomogram model in predicting MVI was detected in the two groups by the computer consistency coefficient (C-index) and calibration graph method. The predictive value was evaluated by receiver operating characteristic curve. Results Histopathological diagnosis revealed 278 patients with MVI and no MVI in the 301 patients of HCC out of the 579 patients in the model group. In the validation group, there were 119 patients with MVI and 100 patients with no MVI out of the 219 patients. Total bilirubin >15 μmol/L(OR=1.519, 95%CI: 1.041~2.217), alkaline phosphatase >60 U/L(OR=1.681, 95%CI: 1.059~2.670), alpha-fetoprotein >200 ng/L (OR=2.192, 95%CI: 1.531~3.134) and tumor maximum diameter (OR=1.120, 95%CI: 1.057~1.187) were the independent risk factors of MVI on multivariate analysis. After establishment of the nomogram model using the independent risk factors, the C-indexes were 0.680 and 0.773 respectively in the model group and the validation group. In the calibration graph, the standard curve properly fitted with the predicting calibration curve. The predicted value of MVI obtained was in good agreement with the observed value. The ROC curve analysis nomogram model predicted the low performance of MVI. Conclusion The nomogram model in predicting MVI in patients with HCC was successfully established. The model offered certain guiding significance in the clinical treatment of HCC. Key words: Carcinoma, hepatocellular; Risk factors; Microvascular invasion; Nomogram