Prognostic Impact of Early Treatment and Oxaliplatin Discontinuation in Patients With Stage III Colon Cancer: An ACCENT/IDEA Pooled Analysis of 11 Adjuvant Trials.

PURPOSE: Oxaliplatin-based adjuvant chemotherapy in patients with stage III colon cancer (CC) for 6 months remains a standard in high-risk stage III patients. Data are lacking as to whether early discontinuation of all treatment (ETD) or early discontinuation of oxaliplatin (EOD) could worsen the prognosis. MATERIALS AND METHODS: We studied the prognostic impact of ETD and EOD in patients with stage III CC from the ACCENT/IDEA databases, where patients were planned to receive 6 months of infusional fluorouracil, leucovorin, and oxaliplatin or capecitabine plus oxaliplatin. ETD was defined as discontinuation of treatment and EOD as discontinuation of oxaliplatin only before patients had received a maximum of 75% of planned cycles. Association between ETD/EOD and overall survival and disease-free survival (DFS) were assessed by Cox models adjusted for established prognostic factors. RESULTS: Analysis of ETD and EOD included 10,447 (20.9% with ETD) and 7,243 (18.8% with EOD) patients, respectively. Compared with patients without ETD or EOD, patients with ETD or EOD were statistically more likely to be women, with Eastern Cooperative Oncology Group performance status ≥ 1, and for ETD, older with a lower body mass index. In multivariable analyses, ETD was associated with a decrease in disease-free survival and overall survival (hazard ratio [HR], 1.61, P < .001 and HR, 1.73, P < .001), which was not the case for EOD (HR, 1.07, P = .3 and HR, 1.13, P = .1). However, patients who received < 50% of the planned cycles of oxaliplatin had poorer outcomes. CONCLUSION: In patients treated with 6 months of oxaliplatin-based chemotherapy for stage III CC, ETD was associated with poorer oncologic outcomes. However, this was not the case for EOD. These data favor discontinuing oxaliplatin while continuing fluoropyrimidine in individuals with significant neurotoxicity having received > 50% of the planned 6-month chemotherapy.

Duration of Adjuvant Chemotherapy for Stage III Colon Cancer.

BACKGROUND: Since 2004, a regimen of 6 months of treatment with oxaliplatin plus a fluoropyrimidine has been standard adjuvant therapy in patients with stage III colon cancer. However, since oxaliplatin is associated with cumulative neurotoxicity, a shorter duration of therapy could spare toxic effects and health expenditures. METHODS: We performed a prospective, preplanned, pooled analysis of six randomized, phase 3 trials that were conducted concurrently to evaluate the noninferiority of adjuvant therapy with either FOLFOX (fluorouracil, leucovorin, and oxaliplatin) or CAPOX (capecitabine and oxaliplatin) administered for 3 months, as compared with 6 months. The primary end point was the rate of disease-free survival at 3 years. Noninferiority of 3 months versus 6 months of therapy could be claimed if the upper limit of the two-sided 95% confidence interval of the hazard ratio did not exceed 1.12. RESULTS: After 3263 events of disease recurrence or death had been reported in 12,834 patients, the noninferiority of 3 months of treatment versus 6 months was not confirmed in the overall study population (hazard ratio, 1.07; 95% confidence interval [CI], 1.00 to 1.15). Noninferiority of the shorter regimen was seen for CAPOX (hazard ratio, 0.95; 95% CI, 0.85 to 1.06) but not for FOLFOX (hazard ratio, 1.16; 95% CI, 1.06 to 1.26). In an exploratory analysis of the combined regimens, among the patients with T1, T2, or T3 and N1 cancers, 3 months of therapy was noninferior to 6 months, with a 3-year rate of disease-free survival of 83.1% and 83.3%, respectively (hazard ratio, 1.01; 95% CI, 0.90 to 1.12). Among patients with cancers that were classified as T4, N2, or both, the disease-free survival rate for a 6-month duration of therapy was superior to that for a 3-month duration (64.4% vs. 62.7%) for the combined treatments (hazard ratio, 1.12; 95% CI, 1.03 to 1.23; P=0.01 for superiority). CONCLUSIONS: Among patients with stage III colon cancer receiving adjuvant therapy with FOLFOX or CAPOX, noninferiority of 3 months of therapy, as compared with 6 months, was not confirmed in the overall population. However, in patients treated with CAPOX, 3 months of therapy was as effective as 6 months, particularly in the lower-risk subgroup. (Funded by the National Cancer Institute and others.).

Randomized phase III study of panitumumab with fluorouracil, leucovorin, and irinotecan (FOLFIRI) compared with FOLFIRI alone as second-line treatment in patients with metastatic colorectal cancer.

PURPOSE: Panitumumab is a fully human anti-epidermal growth factor receptor (EGFR) monoclonal antibody that improves progression-free survival (PFS) in chemotherapy-refractory metastatic colorectal cancer (mCRC). This trial evaluated the efficacy and safety of panitumumab plus fluorouracil, leucovorin, and irinotecan (FOLFIRI) compared with FOLFIRI alone after failure of initial treatment for mCRC by tumor KRAS status. PATIENTS AND METHODS: Patients with mCRC, one prior chemotherapy regimen for mCRC, Eastern Cooperative Oncology Group performance status 0 to 2, and available tumor tissue for biomarker testing were randomly assigned 1:1 to panitumumab 6.0 mg/kg plus FOLFIRI versus FOLFIRI every 2 weeks. The coprimary end points of PFS and overall survival (OS) were independently tested and prospectively analyzed by KRAS status. RESULTS: From June 2006 to March 2008, 1,186 patients were randomly assigned 1:1 and received treatment. KRAS status was available for 91% of patients: 597 (55%) with wild-type (WT) KRAS tumors, and 486 (45%) with mutant (MT) KRAS tumors. In the WT KRAS subpopulation, when panitumumab was added to chemotherapy, a significant improvement in PFS was observed (hazard ratio [HR] = 0.73; 95% CI, 0.59 to 0.90; P = .004); median PFS was 5.9 months for panitumumab-FOLFIRI versus 3.9 months for FOLFIRI. A nonsignificant trend toward increased OS was observed; median OS was 14.5 months versus 12.5 months, respectively (HR = 0.85, 95% CI, 0.70 to 1.04; P = .12); response rate was improved to 35% versus 10% with the addition of panitumumab. In patients with MT KRAS, there was no difference in efficacy. Adverse event rates were generally comparable across arms with the exception of known toxicities associated with anti-EGFR therapy. CONCLUSION: Panitumumab plus FOLFIRI significantly improved PFS and is well-tolerated as second-line treatment in patients with WT KRAS mCRC.

Randomized phase III trial comparing biweekly infusional fluorouracil/leucovorin alone or with irinotecan in the adjuvant treatment of stage III colon cancer: PETACC-3.

PURPOSE The primary objective of this randomized, multicenter, phase III trial was to investigate whether the addition of irinotecan to the de Gramont infusional fluorouracil (FU)/leucovorin (LV) adjuvant regimen (LV5FU2) would improve disease-free survival (DFS) in patients with stage III colon cancer. PATIENTS AND METHODS After curatively intentioned surgery, patients with stage II and III colon cancer were randomly allocated surgery to receive LV5FU2 (LV 200 mg/m(2) as a 2-hour infusion, followed by FU; as a 400 mg/m(2) bolus and then a 600 mg/m(2) continuous infusion over 22 hours, days 1 and 2, every 2 weeks for 12 cycles: de Gramont regimen) with or without irinotecan (180 mg/m(2) as a 30- to 90-minute infusion, day 1, every 2 weeks). In total, 260 (7.9%) of 3,278 patients received an alternative high-dose infusional FU/LV regimen (Arbeitsgemeinschaft Internische Onkologie regimen) with or without irinotecan. Results The principal efficacy analysis was based on 2,094 treated patients with stage III disease, randomly allocated in the LV5FU2 strata. After a median follow-up of 66.3 months, the 5-year DFS rate was 56.7% with irinotecan/LV5FU2 and 54.3% with LV5FU2 alone (primary end point: log-rank P = .106). Combining irinotecan with LV5FU2 did not significantly improve overall survival in this patient group compared with LV5FU2 alone (5-year rate 73.6% v 71.3%, respectively; log-rank P = .094). The addition of irinotecan to LV5FU2 was associated with an increased incidence of grade 3 to 4 GI events and neutropenia. CONCLUSION Irinotecan added to LV5FU2 as adjuvant therapy did not confer a statistically significant improvement in DFS or overall survival in patients with stage III colon cancer compared with LV5FU2 alone.

Capecitabine/oxaliplatin, a safe and active first-line regimen for older patients with metastatic colorectal cancer: post hoc analysis of a large phase II study.

PURPOSE: The tumor-activated fluoropyrimidine capecitabine achieves response rates superior to those of bolus 5-fluorouracil/leucovorin (5-FU/LV) as first-line treatment for metastatic colorectal cancer (CRC), with favorable safety and fewer hospitalizations. Capecitabine is also at least as effective as bolus 5-FU/LV in the adjuvant setting, again with a favorable safety profile. Improved outcomes with capecitabine versus bolus 5-FU/LV in the adjuvant setting have been shown in overall trial populations and in patients aged >or= 70 years. Capecitabine/oxaliplatin (XelOx) is a safe and active combination for the first-line treatment of metastatic CRC. PATIENTS AND METHODS: This post hoc analysis of a large phase II trial compared data from older and younger patients treated with first-line XelOx: oxaliplatin 130 mg/m(2) intravenously on day 1 followed by oral capecitabine 1,000 mg/m(2) twice daily for 14 days every 3 weeks. RESULTS: The median age of the overall population (N = 96) was 64 years (range, 34-79 years), including 52 younger patients (< 65 years of age) and 44 older patients (>or= 65 years of age). Both age groups received a median of 8 cycles (range, 1-26 cycles) of XelOx. The XelOx regimen had similar high activity in both groups, with response rates of 58% (95% CI, 43%-71%) and 52% (95% CI, 37%-68%) in younger and older patients, respectively. In addition, time to disease progression and overall survival were similar in both groups (P > 0.5 for both outcomes). The XelOx regimen also had a favorable safety profile, with no clinically relevant differences between older and younger patients. The overall incidence of adverse events (including grade 3/4), dose reductions, and withdrawals because of adverse events were similar in both groups. CONCLUSION: In the context of an aging population, XelOx provides a highly effective and tolerable first-line treatment for patients with metastatic CRC.