Evaluation of Medium-Term Efficacy of Y90 Radiation Segmentectomy vs Percutaneous Microwave Ablation in Patients with Solitary Surgically Unresectable < 4 cm Hepatocellular Carcinoma: A Propensity Score Matched Study

Abstract

Objective: To evaluate the efficacy and safety of Y90 radiation segmentectomy (RS) vs. percutaneous microwave ablation (MWA) in patients with solitary HCC ≤ 4 cm.

Methods: From 2014 to 2017, 68 consecutive treatment naïve patients were included (34 per treatment arm). Chi-square and t-test were used to evaluate differences in baseline demographics between groups. Objective response was evaluated using mRECIST and toxicity using CTCAE. Overall survival (OS) and progression free survival (PFS) in the targeted tumor and the remainder of liver from initial treatment was calculated using Kaplan-Meier estimation. Propensity score matching was then performed with n = 24 patients matched in each group. Similar outcome analysis was then pre-formed.

Results: In the overall study population, both groups had similar baseline characteristics with the exception of larger lesions in the RS group. There was no difference in toxicity, objective tumor response, OS and non-target liver PFS between the MWA and RS group (p's > 0.05). In the matched cohort, the objective tumor response was 82.6% in MWA vs. 90.9%% in RS (p = 0.548). The mean OS in the MWA group (44.3 months) vs RS (59.0 months; p = 0.203). The targeted tumor mean PFS for the MWA groups was 38.6 months vs. 57.8 months in RS group (p = 0.005). There was no difference overall PFS and toxicity between the 2 matched groups.

Conclusions: Our data suggest Y90 RS achieves similar tumor response and OS with a similar safety compared to MWA in the management of HCC lesions ≤ 4 cm. Additionally, targeted tumor PFS appears to be prolonged in the RS group with similar non-target liver PFS between RS and MWA group.

Keywords: HCC hepatocellular carcinoma; Percutaneous microwave ablation; Y90 radiation segmentectomy.