[Study on preoperative prediction of microvascular invasion based on contrast-enhanced ultrasound habitat imaging combined with peritumoral radiomics in hepatocellular carcinoma].

Objective: Hepatocellular carcinoma has a poor prognosis, and microvascular invasion (MVI) is an important indicator for guiding surgical decisions and influencing long-term survival. This study aims to explore the application value of habitat imaging combined with peritumoral radiomics in the preoperative assessment of MVI based on contrast-enhanced ultrasound (CEUS) images in hepatocellular carcinoma. Methods: The contrast-enhanced ultrasound images and clinical data of 186 patients with pathologically confirmed hepatocellular carcinoma at the First Affiliated Hospital of Guangxi Medical University were retrospectively analyzed and randomly divided into a training group (n=130) and a test group (n=56) in a 7∶3 ratio. Eleven clinical indicators, such as patient age and alpha-fetoprotein (AFP) were extracted. Microvascular invasion (MVI)-independent risk factors were screened to construct clinical prediction models for tumors. Peritumoral and intratumoral regions of interest (ROIs) were depicted at 5 mm and 10 mm on arterial and delayed CEUS phase images. Traditional radiomic features were extracted. Corresponding prediction models were constructed. The above-mentioned depicted intratumoral regions of interest were concurrently applied using K-means clustering to divide the tumor habitat subregions, habitat features, and establish an intratumoral habitat model. Furthermore, a combined model was constructed by integrating a habitat with 5 mm peritumoral features. The predictive efficacy of each model was comprehensively evaluated using indicators such as the area under the receiver operating characteristic (AUC), calibration curve, and decision curve. Results: The clinical model had poorly performed predictions for MVI (training set AUC=0.762; validation set AUC=0.668). The 5 mm peritumoral radiomics model showed better generalization ability and stability than the 10 mm peritumoral and intratumoral models (training set AUC=0.785 vs. 0.786, 0.802; validation set AUC=0.727 vs. 0.672, 0.708). The intratumoral habitat model (training set AUC=0.824; validation set AUC=0.753) was more effective in predicting MVI than both the clinical and the traditional radiomics models in hepatocellular carcinoma. Furthermore, the predictive efficacy of MVI with the selection of a constructed intratumoral habitat combined with 5 mm peritumoral was improved (training set AUC=0.888; test set AUC=0.843), with accuracy, sensitivity, specificity, and clinical net benefit all significantly higher than those of other models. The classification ability had a positive improvement effect. Conclusion: Intratumoral habitat analysis can effectively assess the MVI status based on contrast-enhanced ultrasound in patients with hepatocellular carcinoma. In addition, the combined 5-mm peritumoral radiomics model can more accurately assess the MVI status in patients with hepatocellular carcinoma.