[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.