Adding selective internal radiation therapy to FOLFOX-based (fluorouracil, leucovorin, oxaliplatin) first-line chemotherapy in patients with metastatic colorectal cancer (mCRC) and liver metastases significantly delayed disease progression in the liver, a study published in the Journal of Clinical Oncology has shown.1
SIRT is a form of radiotherapy that uses yttrium-90 resin microspheres and is typically used for patients with unresectable cancers, particularly those with liver cancer or liver metastases. For the SIRFLOX study, researchers sought to evaluate the safety and efficacy of adding SIRT to FOLFOX-based chemotherapy in treatment-naïve patients with mCRC.
Researchers enrolled 530 patients with previously untreated CRC and randomly assigned them 1:1 to receive modified FOLFOX6 ± bevacizumab with SIRT or without SIRT.
Researchers found that median progression-free survival in the liver was 20.5 months and 12.6 months, respectively (HR, 0.69; 95% CI: 0.55-0.90; P=.002). Objective response rate in the liver was improved with SIRT, as well (78.7% vs 68.8%; P=.042).
In contrast, results showed that median progression-free was 10.7 months with SIRT compared with 10.2 months without it (HR, 0.93; 95% CI: 0.77-1.12; P=.43). There was also no significant difference in objective response rates at any site between the 2 groups (76.4% vs 68.1%, respectively; P=.113).
In terms of safety, grade 3 or higher adverse events were reported in 85.4% of patients in the SIRT group and 73.4% of those in the control arm. The safety profile was consistent with previous studies.
1. van Hazel GA, Heinemann Vv, Sharma NK, et al. SIRFLOX: randomized phase III trial comparing first-line mFOLFOX6 (plus or minus bevacizumab) versus mFOLFOX6 (plus or minus bevacizumab) plus selective internal radiation therapy in patients with metastatic colorectal cancer [published online ahead of print February 22, 2016]. J Clin Oncol. doi:10.1200/JCO.2015.66.1181.