Is yttrium-90 radioembolization a viable treatment option for unresectable, chemorefractory colorectal cancer liver metastases? A large single-center experience of 302 patients.

INTRODUCTION: We report the largest series to date on the safety and efficacy of yttrium-90 (90Y) radioembolization for the treatment of unresectable, chemorefractory colorectal cancer liver metastases (CRCLM).
METHODS: A total of 302 patients underwent resin-based 90Y radioembolization for unresectable, chemorefractory CRCLM between 2006 and 2013 in Sydney, Australia. All patients were followed up with imaging studies at regular intervals until death. Radiologic response was evaluated with the response criteria in solid tumors criteria. Clinical toxicities were prospectively recorded. Survival was calculated by the Kaplan-Meier method, and potential prognostic variables were identified on univariate and multivariate analysis.
RESULTS: Median follow-up in the complete cohort was 7.2 months (range 0.2-72.8), and the median survival after 90Y radioembolization was 10.5 months with a 24-month survival of 21%. On imaging follow-up of 293 patients who were followed up beyond 2 months, complete response to treatment was observed in 2 patients (1%), partial response in 111 (38%), stable disease in 96 (33%), and progressive disease in 84 (29%). Four factors were independently associated with a poorer prognosis: extensive tumor volume, number of previous lines of chemotherapy, poor radiological response to treatment, and low preoperative hemoglobin. One hundred fifteen (38%) developed clinical toxicity after treatment; most complications were minor (grade I/II) and resolved without active intervention.
CONCLUSIONS: 90Y radioembolization is a safe and effective treatment for unresectable, chemorefractory CRCLM.