Hepatic Artery Infusion Chemotherapy Compared to Transarterial Radioembolization For Unresectable Colorectal Liver Metastases

Abstract

Objective: This study evaluates outcomes for patients with unresectable colorectal liver metastases (CRLM) undergoing hepatic artery infusion chemotherapy (HAI) and transarterial radioembolization (TARE).

Summary background data: The most common liver-directed therapies for unresectable CRLM include HAI and TARE.

Methods: In this retrospective cohort study, patients with unresectable CRLM treated with HAI at one high-volume center were compared with patients treated with TARE at five other institutions. Propensity score matching was performed within lines of chemotherapy received prior to treatment (treatment-naïve; 1-line; 2-lines; 3-4 lines) using baseline demographics, extrahepatic disease (EHD), prior chemotherapy, disease-free interval, and interval from primary diagnosis to HAI/TARE. Overall survival (OS) analysis was conducted to compare the matched groups.

Results: A total of 708 HAI patients and 481 TARE patients were identified. The majority of patients (84%) received chemotherapy prior to HAI/TARE. HAI patients were younger (median age:54 vs. 62) and more likely to have evidence of EHD at time of treatment (65% vs. 60%). Of the 493 patients who received 1-line of chemotherapy, 166 (34%) were matched. Among matched patients who received 1-line (HAI:83, TARE:83) or 2-lines of chemotherapy (HAI:80, TARE:80), TARE patients had a significantly increased risk of all-cause mortality compared to HAI [HR:1.46 (95%CI:1.02-2.08) and HR:1.96 (95%CI:1.32-2.89)]. More frequent conversion to resection and use of concurrent systemic chemotherapy were also seen in the HAI cohort. Among matched patients who received 3-4 lines of chemotherapy (HAI:50, TARE:50), there was no difference in OS between HAI and TARE [HR:0.88 (95%CI:0.57-1.35)] and rate of conversion to surgery was 4% for both groups.

Conclusions: Within matched cohorts stratified by lines of therapy, there appear to be differences in survival for patients treated with HAI and TARE after first or second-line chemotherapy. Outcomes after TARE and HAI are not significantly different in the refractory setting.

Keywords: HAI; TARE; colorectal liver metastases.