4:21 PMAbstract No. 68 - Thermal ablation versus surgical resection for the treatment of T1 hepatocellular carcinoma in the Surveillance, Epidemiology, and End Results (SEER) Program database population

Abstract

The effectiveness of thermal ablation for small hepatocellular carcinomas (HCCs) compared to surgical resection continues to be debated. Some randomized controlled trials and meta-analyses suggest equivalence, whereas others suggest benefits to surgery. The purpose of this study was to review recent SEER data to compare the effectiveness of thermal ablation (TA) and surgical resection (SR) in the treatment of T1 HCC (<5 cm solitary tumor without vascular invasion). This study was IRB exempt. SEER data was searched for records with a histological diagnosis of T1 HCC during the years 2004-2012. Comparison was made between TA and SR as the primary treatment. Patients who underwent liver transplantation were excluded. Comparison of tumor size and patient age between groups was performed using the t-test. Comparison of survival was made using the log rank test. For the 772 patients who had <3 cm HCCs, 552 underwent TA and 220 had SR. There was no significant difference in mean patient age (TA 61.4 years, SR 61.5 years, p=0.564) or mean tumor size (2.2 cm for both groups, p=0.280). There was no significant difference in overall survival (OS; p=0.232) or disease specific survival (p=0.070). The 1, 2, 3, 4, and 5 year OS rates were 91, 77, 64, 53, and 44% for TA, and 90, 79, 71, 62, and 53% for SR. For the 267 patients who had HCCs 3.1-4 cm in size, 165 underwent TA and 102 had SR. There was no significant difference in mean patient age (TA 64.8 years, SR 62.6 years, p=0.111). Resected tumors were 1 mm larger on average (TA 3.5 cm, SR 3.6 cm, p=0.005).There were significant differences in OS (p=0.0001) and disease specific survival (p=0.038) which favored surgery. The 1, 2, 3, 4, and 5 year OS rates were 76, 62, 47, 36, and 27% for the ablation group, and 88, 79, 67, 59, and 54% for the resection group. There was no significant difference in overall survival or disease specific survival between surgical resection and thermal ablation for T1 HCCs <3 cm in the SEER population. The cohorts did not differ significantly with respect to patient age or tumor size. Significant benefit was observed with surgery for tumors measuring 3.1-4 cm.