First-line multiagent chemotherapy
Three randomized studies in patients with metastatic colorectal cancer demonstrated improved response rates, progression-free survival (PFS), and OS when irinotecan or oxaliplatin was combined with 5-FU/LV.[41,42,43] An intergroup study (NCCTG-N9741) then compared IFL with FOLFOX4 in first-line treatment for patients with metastatic colorectal cancer. Patients assigned to FOLFOX4 experienced improved PFS (median, 6.9 months vs. 8.7 months; P = .014; hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.61–0.89) and OS (15.0 months vs. 19.5 months, P = .001; HR, 0.66; 95% CI, 0.54–0.82) compared with patients randomly assigned to IFL.[Level of evidence: 1iiA] Subsequently, two studies compared FOLFOX with FOLFIRI, and patients were allowed to cross over after progression on first-line therapy, respectively.[44,45][Level of evidence: 1iiDiii] PFS and OS were identical between the treatment arms in both studies. Since the publication of these studies, the use of either FOLFOX or FOLFIRI is considered acceptable for first-line treatment of patients with metastatic colorectal cancer.
The Bolus, Infusional, or Capecitabine with Camptosar-Celecoxib (BICC-C) trial evaluated several different irinotecan-based regimen in patients with previously untreated metastatic colorectal cancer: FOLFIRI, mIFL, and capecitabine/irinotecan (CAPIRI). The study randomly assigned 430 patients and was closed early due to poor accrual. The patients who received FOLFIRI had a better PFS than the patients who received either mIFL (7.6 months vs. 5.9 months, P = .004) or CAPIRI (7.6 months vs. 5.8 months, P = .015). Patients who received CAPIRI had the highest (grade 3 or higher) rates of nausea, vomiting, diarrhea, dehydration, and hand-foot syndrome. After bevacizumab was approved, the BICC-C trial was amended and an additional 117 patients were randomly assigned to receive FOLFIRI/bevacizumab or mIFL/bevacizumab. Although the primary endpoint of PFS was not significantly different, patients receiving FOLFIRI/bevacizumab had a significantly better OS (28.0 months vs. 19.2 months, P = .037; HR for death, 1.79; 95% CI 1.12 to 2.88). When using an irinotecan-based regimen as first-line treatment of metastatic colorectal cancer, FOLFIRI is preferred.[Level of evidence: 1iiDiii] (Refer to the PDQ summary on Nausea and Vomiting and refer to the Diarrhea section in the PDQ summary on Gastrointestinal Complications for information on diarrhea and dehydration.)