Effectiveness of Hepatic Artery Infusion (HAI) Versus Selective Internal Radiation Therapy (Y90) for Pretreated Isolated Unresectable Colorectal Liver Metastases (IU-CRCLM)

Background: In the era of modern effective systemic chemotherapy, the comparative effectiveness of hepatic artery infusion (HAI) versus selective internal radiation therapy (yttrium-90 [Y90]) for pretreated patients with isolated unresectable colorectal liver metastasis (IU-CRCLM) remains unknown. This study sought to compare the overall survival (OS) after HAI versus Y90 for IU-CRCLM patients treated with modern chemotherapy and to perform a cost analysis of both regional methods. Methods: This study retrospectively reviewed patients receiving HAI or Y90 in combination with modern chemotherapy as second-line therapy for IU-CRCLM. Overall survival was calculated from the time of IU-CRCLM diagnosis. Uni- and multivariate models were constructed to identify independent predictors of survival. Results: The inclusion criteria were met by 97 patients (48 HAI patients and 49 Y90 patients). Both groups were similar in terms of age, gender, body mass index (BMI), synchronous disease, carcinoembryonic antigen (CEA), liver tumor burden, and chemotherapy-related characteristics including use of biologics and lines of chemotherapy (all p > 0.05). The HAI group had a better OS than the Y90 group (31.2 vs. 16.3 months; p < 0.001). A trend toward reduced cost favored the HAI group (median, $29,479 vs. $39,092; p = 0.296). The multivariate analysis showed that receipt of HAI (hazard ratio 0.465) and number of chemotherapy lines (HR 0.797) were associated with improved OS from the date of IU-CRCLM diagnosis. Conclusions: This is the first study to evaluate the comparative effectiveness of HAI versus Y90 in the era of modern chemotherapy, and the findings suggests that HAI is associated with better survival than Y90 for patients with pretreated IU-CRCLM.