Rate of Curative Surgery in Real-world Patients with Unresectable Metastatic Colorectal Cancer Treated with FOLFOXIRI ± Bevacizumab: A Western Canadian Province Experience

Background Recent evidence from randomized trials suggests that FOLFOXIRI (fluorouracil, oxaliplatin, and irinotecan) ± bevacizumab is associated with higher response rates, with the potential for conversion of unresectable to resectable disease in metastatic colorectal cancer (mCRC). However, limited evidence is available on the efficacy and safety of this regimen in real-world patients with mCRC. The current study aims to evaluate the conversion rate and safety of FOLFOXIRI ± bevacizumab in real-world patients with unresectable mCRC. Methods In this retrospective multicenter population-based cohort study, patients who were diagnosed with unresectable mCRC between January 2015 and December 2018 in Saskatchewan and received FOLFOXIRI ± bevacizumab were assessed. Kaplan-Meier survival methods and the log-rank test were performed. Results A total of 28 eligible patients with a median age of 51 years (interquartile range 39-60) and a male:female ratio of 11:17 were identified; 39% had rectal cancer, 46% had extrahepatic disease, and 46% had bilobar liver metastases. Overall, 63% of the patients had a positive response to FOLFOXIRI ± bevacizumab and 53% underwent metastasectomy. Of all patients 60% had grade 3/4 toxicity and 32% required hospital admission. No treatment-related mortality was noted. After 4 years, 50% of the patients were alive. Median progression-free survival of patients who underwent surgery was 18 months (95% CI 11.3-24.7) versus 11 months (4-18.1) without surgery (p = 0.28). Median overall survival of patients with surgery was 33 months (17.5-48.5) versus 16 months (8.3-23.7) without surgery (p = 0.03). Conclusion The current study suggests that FOLFOXIRI ± bevacizumab therapy in real-world patients with mCRC is associated with a high rate of conversion from unresectable to resectable metastatic disease. Patients with metastasectomy had better survival.