Early experience with 70-150 m irinotecan drug-eluting beads (M1-DEBIRI) for the treatment of unresectable hepatic colorectal metastases

Aim: To report our early experience on the feasibility and safety of 70-150 m drug-eluting beads loaded with irinotecan (M1-DEBIRI) for treating unresectable hepatic colorectal metastases. Patients and Methods: An Institutional Review Board-approved, prospectively maintained, multi-institutional registry was evaluated from 2/2009 to 8/2013. Fifteen consecutive patients presenting with liver-dominant metastatic colorectal cancer were treated with M1-DEBIRI. Kaplan-Meier statistics was used to evaluate hepatic progression-freesurvival and overall survival. Results: Fifteen patients underwent 32 DEBIRI treatments. The mean prescribed dose was 100 mg of irinotecan (range=100-200 mg). In 75% of treatments (n=24), 100% of the prescribed dose was delivered before complete stasis. In 97% of treatments (n=31), at least 50% (median 100 mg, range 25-150 mg) of the prescribed dose was delivered. There was grade 2 abdominal pain after one treatment (3%). In another patient, increased total bilirubin (1.1 to 3.1 mg/dl) was seen after one treatment. There was 42% reduction in median carcinoembryonic antigen level and 33% (5/15 patients) with Response Evaluation Criteria in Solid Tumors (RECIST) objective response (complete and partial). Modified RECIST and European Association for the study of the Liver (EASL) objective response rates were both 73% (11/15 patients). The disease control rate was 93% (14/15 patients). Hepatic progression-free-survival and overall survival were 8 and 13 months respectively. Disease in one patient was down-staged to resection (6%). Conclusion: M1-DEBIRI appears to be safe and feasible in the treatment of metastatic colorectal cancer. Smaller beads also provide efficient irinotecan dose delivery. Larger studies are needed to validate these findings.