As reported in the Journal of Clinical Oncology by Iveson et al, final results of the UK-based noninferiority phase III SCOT trial have shown noninferiority of 3 vs 6 months of adjuvant oxaliplatin plus fluoropyrimidine chemotherapy in overall survival among patients with colorectal cancer. Noninferiority was achieved with 3 vs 6 months of capecitabine and oxaliplatin (CAPOX) but not for 3 vs 6 months of fluorouracil, leucovorin, and oxaliplatin (FOLFOX).
Study Details
In the trial, 6,088 patients were randomly assigned between March 2008 and November 2013 to receive 3 months (n = 3,044) vs 6 months (n = 3,044) of adjuvant oxaliplatin plus fluoropyrimidine. Among these, 4,109 (67.5%; 2,053 vs 2,056) received CAPOX and 1,979 (32.5%; 991 vs 988) received FOLFOX. The original report from the trial showed noninferior disease-free survival with reduced toxicity and improved quality of life with 3 vs 6 months of adjuvant treatment. The current report provides overall survival outcomes after extended follow-up.
Key Findings
Among all patients, 5-year overall survival was 82.4% (95% confidence interval [CI] = 80.9%–83.8%) in the 3-month group vs 82.4% (95% CI = 81.0%–83.8%) in the 6-month group (hazard ratio [HR] = 0.96, 95% CI = 0.86–1.07, noninferiority P = .0033).
Among patients receiving CAPOX, 5-year overall survival was 82.5% (95% CI = 80.8%–84.2%) in the 3-month group vs 81.4% (95% CI = 79.7%–83.2%) in the 6-month group (HR = 0.90, 95% CI = 0.79–1.03, noninferiority P = .00052).
Among patients receiving FOLFOX, 5-year overall survival was 82.0% (95% CI = 79.6%–84.6%) in the 3-month group vs 84.4% (95% CI = 82.0%–86.8%) in the 6-month group (HR = 1.10, 95% CI = 0.90–1.34, noninferiority P =.38354).
Among 1,101 patients with rectal cancer, 5-year overall survival in the 3-month group vs the 6-month group was 88.6% vs 87.3% among all patients, 89.8% vs 88.1% among those receiving CAPOX, and 86.4% vs 85.6% among those receiving FOLFOX.
The investigators concluded: “…SCOT has shown noninferiority for [overall survival] with 3 months of adjuvant chemotherapy treatment, which should be recommended for most patients.”
David Church, MBChB, FRCP, DPhil, of the Department of Oncology, University of Oxford, Oxford, UK, is the corresponding author for the Journal of Clinical Oncology article.
DISCLOSURE: The study was supported by Cancer Research UK and others. For full disclosures of the study authors, visit ascopubs.org.
