Efficacy of combined modality conversion therapy for HCC with portal vein tumor thrombus: a retrospective cohort study.

BACKGROUND

Unresectable hepatocellular carcinoma (uHCC) patients with portal vein tumor thrombus (PVTT) have a substandard prognosis. This study elucidated whether conversion therapy can alleviate unresectable tumors and increase the rate of salvage hepatectomy, as well as identify predictors of better prognosis.

METHODS

This retrospective study analyzed 159 patients with uHCC and PVTT who underwent conversion therapy, predominantly combining systemic treatments with transarterial chemoembolization (TACE). Primary endpoints were progression-free survival (PFS) and overall survival (OS). Secondary endpoints included tumor response, surgical conversion rate, and outcomes in the surgical cohort.

RESULTS

The data showed that the objective response rates (ORR) for the entire cohort (n = 159) were 42.1%, while the disease control rate was 62.3%. The median PFS and OS were respectively determined to be 9.6 and 17.7 months. Moreover, 40 patients (25.2%) were successfully converted and underwent salvage hepatectomy. In addition, the surgical subgroup indicated a markedly improved median recurrence-free survival (RFS; 10.1 months) and OS (30 months). Multivariate analysis revealed that salvage hepatectomy was an independent protective factor for both PFS (95% CI: 0.341 - 0.845, HR = 0.537, p = 0.007) and OS (95% CI: 0.273 - 0.777, HR = 0.460, p = 0.004). Whereas for poorer outcomes, an independent predictor was advanced Cheng's PVTT classification (OS: HR = 1.719, p < 0.001). Multivariate logistic regression showed that a single tumor (OR = 0.402, p = 0.024) and a lower baseline aspartate aminotransferase level (OR = 0.453, p = 0.038) were independent predictors of successful conversion to surgery. Of the 40 surgical patients, 11 (27.5%) attained a pathologic complete response (pCR). Although patients with pCR showed a numerically favorable survival trend (median RFS of 14.0 months vs. 4.5 months for major pathological response), this difference did not reach statistical significance. Adverse events associated with treatment were manageable, with grade ≥ 3 adverse events observed in 19.5% of patients.

CONCLUSION

This retrospective study evaluated the combined effect of systemic therapy and TACE as an efficient conversion therapy for uHCC patients with PVTT. The findings revealed a substantial response rate, facilitating curative-intent surgery in a substantial percentage of patients. Salvage hepatectomy was associated with improved survival in selected patients who responded to conversion therapy.