To evaluate the predictive value of fibrinogen (FIB)-to-albumin (ALB) ratio (FAR) for microvascular invasion (MVI) in hepatocellular carcinoma (HCC).

Clinical data of 193 patients with liver cancer who underwent surgical treatment in Beijing Hospital from January 2013 to October 2020 were retrospectively analyzed. The informed consents of all patients were obtained and the local ethical committee approval was received. Among them, 162 patients were male and 31 female, aged (60±13) years on average. 88 cases were confirmed with MVI by postoperative pathological examination. Preoperative serum FIB, ALB and other data were collected and the FAR was calculated. The diagnostic value of FAR was analyzed by the ROC curve. The influencing factors of MVI were assessed by Logistic regression model. According to the results of multivariate analysis, the nomogram for predicting MVI was established. The prediction efficacy of this nomogram was evaluated by Unreliability test.

When the optimal cut-off value of FAR in diagnosing MVI was 0.057, all patients were divided into high group (n=130) and low FAR group (n=63). Multivariate Logistic regression analysis showed that tumor diameter ≥3 cm (OR=3.263, 95%CI: 1.300-6.261, P=0.010), AFP≥400 μg/L (OR=2.818, 95%CI:1.214-6.542, P=0.016); AFP 20-400 μg/L,(OR=2.326, 95%CI:1.026-5.271, P=0.043), total protein (OR=1.107, 95%CI:1.038-1.181, P=0.002) and FAR (OR=2.600, 95%CI:1.079-6.261, P=0.033) were independent risk factors for MVI. Tumor diameter, AFP, total protein and FAR were included in the nomogram, and the area under the ROC curve was 0.755, and the calibration curve showed high efficacy (P=0.956).

Clinical prediction model for MVI of liver cancer based on FAR is simple and reliable, which contributes to early identification of high-risk HCC patients with MVI and making more precise treatment regimens.