High rates of treatment stage migration for early hepatocellular carcinoma and association with adverse outcomes: An Australian multicenter study

Background and Aim: The rate of contraindications to percutaneous ablation (PA) for inoperable early hepatocellular carcinoma (HCC) and subsequent outcomes is not well described. We investigated the prevalence and outcomes of inoperable early HCC patients with contraindications to PA, resulting in treatment stage migration (TSM). Methods: Barcelona Clinic Liver Cancer (BCLC) 0/A patients diagnosed between September 2013 and September 2019 across five hospitals were identified. Primary endpoint was proportion of BCLC 0/A HCCs with contraindications to PA. Secondary endpoints included overall survival (OS), local tumor control (LTC), and recurrence-free survival (RFS). The causal effects of PA versus TSM were assessed using a potential outcome means (POM) framework in which the average treatment effects (ATEs) of PA were estimated after accounting for potential selection bias and confounding. Results: Two hundred twenty patients with inoperable BCLC 0/A HCC were identified. One hundred twenty-two patients (55.5%) had contraindications to PA and received TSM therapy, 98 patients (44.5%) received PA. The main contraindication to PA was difficult tumor location (51%). Patients who received TSM therapy had lower median OS (2.4 vs 5.3 years), LTC (1.0 vs 4.8 years), and RFS (0.8 vs 2.9 years); P < 0.001, respectively, compared with PA. The ATE for PA versus TSM yielded an additional 1.11 years (P = 0.019), 2.45 years (P < 0.001), and 1.64 years (P < 0.001) for OS, LTC, and RFS, respectively. Three-year LTC after PA was suboptimal (65%). Conclusion: Our study highlights high rates of contraindication to PA in early HCCs, resulting in TSM and poorer outcomes. The LTC rate for PA appears suboptimal despite being considered as curative therapy. Both findings support the exploration of improved treatment options for early HCCs.