Conversion to complete surgical treatment using hepatic artery infusional chemotherapy in patients with unresectable liver metastases from colorectal cancer.

Abstract

472 Background: Hepatic artery infusional (HAI) chemotherapy effectively treats colorectal liver metastases (CRLM). This study analyzes the combination of HAI and systemic chemotherapy for treating unresectable CRLM, focusing on the conversion to complete resection and/or ablation (R/A) and long term outcomes. Methods: All patients with initially unresectable CRLM treated with HAI and systemic chemotherapy from 2000-2009 were included. Patients who responded sufficiently to undergo complete R/A were compared to those who did not convert. Results: 373 patients were included. 296 (79 %) were previously treated and 77 (21 %) were chemo naïve. 115 (31 %) were on protocol and 258 (69 %) were not on protocol. 93 patients (25%) subsequently underwent complete R/A (conversion group). Of the 115 protocol patients, 47 (41 %) underwent complete R/A. The percentage of patients submitted to complete R/A increased from 16% during 2000-2003 to 30% during 2004-2009. 43% of patients who were chemotherapy-naïve prior to HAI therapy eventually underwent complete R/A, compared to 15% who were initially treated with systemic therapy (p<0.001). Factors associated with conversion on multivariate analysis were more recent treatment (2004-2009), no prior chemotherapy, and a clinical risk score < 3. Overall survival was greater in the conversion group, with a median and predicted 5-year survival from the time of HAI pump placement of 54 months and 49%, compared to 19 months and 6%, respectively (p<0.001). Conclusions: One-quarter of patients with unresectable CRLM responded sufficiently to undergo complete R/A following HAI plus systemic chemotherapy. Conversion was more likely in patients who were chemotherapy-naïve (43 %), had a clinical risk score < 3, and were treated in the more recent era. Survival in the conversion group was significantly better.