切除術対マイクロ波焼灼療法：切除不能肝細胞癌の転換療法後

Conversion therapy may transform some unresectable hepatocellular carcinomas (uHCCs) into curable ones, but data remained limited comparing subsequent curative-intent treatment options. Therefore, we aimed to compare the efficacy and safety of surgical resection (SR) and microwave ablation (MWA) following conversion for initially uHCC.

From June 2008 to October 2022, this multi-center retrospective study included 1035 consecutive patients with treatment-naive BCLC A/B beyond-Milan uHCC receiving curative-intent SR or MWA after successful conversion from 15 tertiary-care hospitals. For the propensity score-matched cohort, overall survival (OS), recurrence-free survival (RFS), and treatment-related complications were compared; a risk-stratification Conversion-Ablation or REsection (CARE) score was developed for OS and externally compared against major prognostic models.

After matching (421 patients in each treatment group), SR was associated with similar RFS (p = 0.167), less beyond-Milan recurrence (p = 0.003), and longer OS (p < 0.001) compared with MWA. Developed as "10 × baseline AFP (>400 ng/mL,1; ≤ 400 ng/mL,0)-baseline albumin (g/L)-35 × objective response to conversion therapy per mRECIST (yes,1;no,0)," CARE outperformed major prognostic models (p values, < 0.001 to 0.025) and allowed effective stratification of OS and RFS (all p < 0.001). OS (p = 0.159) and RFS (p = 0.573) were similar between the two treatment groups for the CARE-identified low-risk patients (≤-46.6), but SR was associated with longer OS (p < 0.001) and RFS (p < 0.001) for the CARE-identified high-risk ones (>-46.6). Treatment-related complications were comparable between two groups (p values, 0.147 to >0.999).

For initially BCLC A/B uHCC beyond the Milan criteria, SR was associated with longer OS and similar RFS compared with MWA after conversion. The CARE score might assist in personalized risk stratification.