Imaging-based surrogate classification for risk stratification of hepatocellular carcinoma with microvascular invasion to adjuvant hepatic arterial infusion chemotherapy: a multicenter retrospective study

Background: Patients with microvascular invasion (MVI)-positive hepatocellular carcinoma (HCC) have shown promising results with adjuvant hepatic arterial infusion chemotherapy (HAIC) with FOLFOX after curative resection. We aim to develop an imaging-derived biomarker to depict MVI-positive HCC patients more precisely and promote individualized treatment strategies of adjuvant HAIC. Materials and Methods: Patients with MVI-positive HCC were identified from five academic centers and utilized for model development (n=470). Validation cohorts were pooled from a previously reported prospective clinical study conducted (control cohort (n=145), adjuvant HAIC cohort (n=143)) (NCT03192618). The primary endpoint was recurrence-free survival (RFS). Imaging features were thoroughly reviewed, and multivariable logistic regression analysis was employed for model development. Transcriptomic sequencing was conducted to identify the associated biological processes. Results: Arterial phase peritumoral enhancement, boundary of the tumor enhancement, tumor necrosis stratification, and boundary of the necrotic area were selected and incorporated into the nomogram for RFS. The imaging-based model successfully stratified patients into two distinct prognostic subgroups in both the training, control, and adjuvant HAIC cohorts (median RFS, 6.00 vs. 66.00 mo, 4.86 vs. 24.30 mo, 11.46 vs. 39.40 mo, all P <0.01). Furthermore, no significant statistical difference was observed between patients at high-risk of adjuvant HAIC and those in the control group ( P =0.61). The area under the receiver operating characteristic curve at two years was found to be 0.83, 0.84, and 0.73 for the training, control, and adjuvant HAIC cohorts respectively. Transcriptomic sequencing analyses revealed associations between the radiological features and immune-regulating signal transduction pathways. Conclusion: The utilization of this imaging-based model could help to better characterize MVI-positive HCC patients and facilitate the precise subtyping of patients who genuinely benefit from adjuvant HAIC treatment.