Abstract
BACKGROUND: The aim of this study was to investigate the effectiveness of adjuvant hepatic arterial infusion pump (HAIP) chemotherapy after complete resection or ablation of recurrent colorectal liver metastases (CRLM). METHODS: A retrospective cohort study was conducted of patients from two centers who were treated with resection and/or ablation of recurrent CRLM only between 1992 and 2018. Overall survival (OS) and hepatic disease-free survival (hDFS) were estimated using the Kaplan-Meier method. The Cox regression method was used to calculate hazard ratios (HRs) with corresponding 95% confidence intervals (CI). RESULTS: Of 374 eligible patients, 81 (22%) were treated with adjuvant HAIP chemotherapy. The median follow-up for survivors was 65 months (IQR 32-118 months). Patients receiving adjuvant HAIP were more likely to have multifocal disease and receive perioperative systemic chemotherapy at time of resection for recurrence. A median hDFS of 46 months (95% CI 29-81 months) was found in patients treated with adjuvant HAIP compared with 18 months (95% CI 15-26 months) in patients treated with resection and/or ablation alone (p = 0.001). The median OS and 5-year OS were 89 months (95% CI 52-126 months) and 66%, respectively, in patients treated with adjuvant HAIP compared with 57 months (95% CI 47-67 months) and 47%, respectively, in patients treated with resection and/or ablation only (p = 0.002). Adjuvant HAIP was associated with superior hDFS (adjusted HR 0.599, 95% CI 0.38-0.93, p = 0.02) and OS (adjusted HR 0.59, 95% CI 0.38-0.92, p = 0.02) in multivariable analysis. CONCLUSION: Adjuvant HAIP chemotherapy after resection and/or ablation of recurrent CRLM is associated with superior hDFS and OS.