Tournigand, Christophe

PurposeProgression-free survival (PFS) has previously been established as a surrogate for overall survival (OS) for first-line metastatic colorectal cancer (mCRC). Because mCRC treatment has advanced in the last decade with extended OS, this surrogacy requires re-examination.MethodsIndividual patient data from 16,762 patients were available from 22 first-line mCRC studies conducted from 1997 to 2006; 12 of those studies tested antiangiogenic and/or anti–epidermal growth factor receptor agents. The relationship between PFS (first event of progression or death) and OS was evaluated by using R2statistics (the closer the value is to 1, the stronger the correlation) from weighted least squares regression of trial-specific hazard ratios estimated by using Cox and Copula models.ResultsForty-four percent of patients received a regimen that included biologic agents. Median first-line PFS was 8.3 months, and median OS was 18.2 months. The correlation between PFS and OS was modest (R2, 0.45 to 0.69). Analyses limited to trials that tested treatments with biologic agents, nonstrategy trials, or superiority trials did not improve surrogacy.ConclusionIn modern mCRC trials, in which survival after the first progression exceeds time to first progression, a positive but modest correlation was observed between OS and PFS at both the patient and trial levels. This finding demonstrates the substantial variability in OS introduced by the number of lines of therapy and types of effective subsequent treatments and the associated challenge to the use of OS as an end point to assess the benefit attributable to a single line of therapy. PFS remains an appropriate primary end point for first-line mCRC trials to detect the direct treatment effect of new agents.

PurposeProgression-free survival (PFS) is not an optimal end point to evaluate therapeutic strategies in advanced colorectal cancer (ACRC). Therefore, composite end points have been proposed to evaluate a chemotherapy strategy when sequential treatments are available: duration of disease control (DDC) and time to failure of strategy (TFS). The goal of this study was to evaluate these alternative end points and their potential surrogacy for overall survival (OS).MethodsWe pooled individual patient data from three randomized trials evaluating chemotherapy strategy, which accrued 1,042 patients with previously untreated ACRC. In these trials, first-line treatment was either oxaliplatin- or irinotecan-based chemotherapy. Compared with TFS, DDC included neither time interval between progression and next sequence of treatment nor time to progression if the best result of the next sequence of treatment was progression.ResultsThere was good correlation between DDC and OS (correlation of median: r, 0.62; correlation of hazard ratio [HR]: adjusted copula R2, 0.72) and between TFS and OS (correlation of median: r, 0.59; correlation of HR: adjusted copula R2, 0.67). There was no correlation between PFS and OS (correlation of median: r, 0.45; correlation of HR: adjusted copula R2, 0.47).ConclusionDDC and TFS roughly achieved the same results. Both are acceptable new end points to evaluate a therapeutic strategy in ACRC. Although TFS achieved a pragmatic evaluation of a multiline strategy, DDC captured the effect of a specific sequence in a therapeutic strategy.

Purpose Oxaliplatin, fluorouracil, and leucovorin are commonly used to treat advanced and resected colorectal cancer. This analysis compares the safety and efficacy of oxaliplatin plus fluorouracil/leucovorin administered bimonthly (FOLFOX4) in patients age younger than and at least 70 years. Patients and Methods This retrospective analysis included 3,742 colorectal cancer patients (614 age ≥ 70) from four clinical trials testing FOLFOX4 in the adjuvant, first-, and second-line settings. End points included grade ≥ 3 adverse events, response rate (in advanced disease), progression or relapse-free survival, dose-intensity, and overall survival in the studies with mature survival data. Results Grade ≥ 3 hematologic toxicity (neutropenia [43% v 49%; P = .04] and thrombocytopenia [2% v 5%; P = .04]) were significantly higher in older patients. Older age was not associated with increased rates of severe neurologic adverse events, diarrhea, nausea/vomiting, infection, overall incidence of grade ≥ 3 toxicity (63% v 67%; P = .15), or 60-day mortality (1.1% v 2.3%; P = .20). The relative benefit of FOLFOX4 versus control did not differ by age for response rate, progression or recurrence free-survival (hazard ratio, 0.70 for FOLFOX4 v control for age < 70, 0.65 for age ≥ 70; P = .42), or overall survival (hazard ratio, 0.77 age < 70, 0.82 age ≥ 70; P = .79). Dose-intensity did not differ by age at cycles 1, 3, 6, or 12. Conclusion FOLFOX4 maintains its efficacy and safety ratio in selected elderly patients with colorectal cancer. Its judicious use should be considered without regard to patient age, although scant data are available among patients older than 80 years.