Outcome of second-line treatment after first-line chemotherapy with the GONO FOLFOXIRI regimen

PURPOSE

FOLFOXIRI demonstrated higher efficacy compared to 5-fluorouracil, leucovorin, irinotecan (FOLFIRI) as first-line treatment of metastatic colorectal cancer. We evaluated the outcome of second-line treatments among 196 patients treated with first-line FOLFOXIRI in three consecutive trials conducted by the Gruppo Oncologico Nord Ovest group.

PATIENTS AND METHODS

One hundred seventy-two of 196 patients so far progressed and 136 (79%) received second-line therapies: 32 (24%) were rechallenged with FOLFOXIRI, 52 (38%) were treated with irinotecan- or oxaliplatin-based doublets, and 52 (38%) received fluoropyrimidine plus mytomicin C or single-agent chemotherapy. Only 10 patients received bevacizumab (3) or cetuximab (7) with chemotherapy. Activity and efficacy data were collected and subgroup analyses were performed according to the regimen administered.

RESULTS

Overall response rate (RR) was 23%; median progression-free survival (PFS) and overall survival (OS) were 5.9 and 13.2 months, respectively. At an exploratory subgroup analysis, retreatment with FOLFOXIRI was associated with longer PFS (8.2 versus 6.3 months; P = .003, hazard ratio [HR] = 0.61) and OS (19.3 versus 14.0 months; P = .02, HR = 0.57) compared with doublets; single-agent chemotherapy or fluoropyrimidine plus mytomicin C was significantly lower in terms of RR (8%), PFS (3.0 months), and OS (8.7 months) compared with FOLFOXIRI or doublets.

CONCLUSIONS

First-line FOLFOXIRI does not impair the efficacy of second-line treatments. In some patients rechallenge with FOLFOXIRI may represent a valid option, although potential imbalances in prognostic factors due to better patient selection should be considered.

Randomized trial of two induction chemotherapy regimens in metastatic colorectal cancer: an updated analysis

BACKGROUND

In a randomized trial with a median follow-up of 18.4 months, 6 months of induction chemotherapy with a three-drug regimen comprising 5-fluorouracil (by continuous infusion)-leucovorin, irinotecan, and oxaliplatin (FOLFOXIRI) demonstrated statistically significant improvements in response rate, radical surgical resection of metastases, progression-free survival, and overall survival compared with 6 months of induction chemotherapy with fluorouracil-leucovorin and irinotecan (FOLFIRI).

METHODS

From November 14, 2001, to April 22, 2005, we enrolled 244 patients with metastatic colorectal cancer. To evaluate if the superiority of FOLFOXIRI is maintained in the long term, we updated the overall and progression-free survival data to include events that occurred up to February 12, 2009, with a median follow-up of 60.6 months. We performed a subgroup and a risk-stratified analysis to examine whether outcomes differed in specific patient subgroups, and we analyzed the results of treatment after progression. Survival curves were estimated by the Kaplan-Meier method. Multivariable Cox regression models were fit to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). All statistical tests were two-sided.

RESULTS

FOLFOXIRI demonstrated statistically significant improvements in median progression-free survival (9.8 vs 6.8 months, HR for progression = 0.59, 95% CI = 0.45 to 0.76, P < .001) and median overall survival (23.4 vs 16.7 months, HR for death = 0.74, 95% CI = 0.56 to 0.96, P = .026) with a 5-year survival rate of 15% (95% CI = 9% to 23%) vs 8% (95% CI = 4% to 14%). The improvements in progression-free survival and, to a lesser extent, in overall survival were evident even when the analysis excluded patients who received radical resection of metastases. With regard to the risk-stratified analysis, FOLFOXIRI results in longer progression-free survival and overall survival than FOLFIRI in all risk subgroups.

CONCLUSIONS

Six months of induction chemotherapy with FOLFOXIRI is associated with a clinically significant improvement in the long-term outcome compared with FOLFIRI with an absolute benefit in survival at 5 years of 7%.