Researchers from the United Kingdom have reported that chemotherapy produces a small (1%-5%) survival benefit for patients with stage B colorectal cancer. These results were presented in an oral session of the 40th annual meeting of the American Society of Clinical Oncology held in New Orleans, Louisiana, June 4-8, 2004.

This study compared adjuvant chemotherapy versus observation in 3,238 patients with colorectal cancer who were apparently cured with resection. Patients were randomized to receive fluorouracil/folinic acid or observation. Chemotherapy consisted of six 5-day, four-weekly or 30 once-weekly courses of intravenous fluorouracil (370mg/m2) with either high-dose (175mg) or low-dose (25mg) L-folinic acid, and with either levamisole or placebo.

With a median follow-up of 4.2 years, risk of death with CT versus control was 0.88 (95%CI 0.75-1.05; p=0.15) and recurrence 0.82 (0.70-0-97; p=0.02). Treatment efficacy did not differ significantly by stage, site or age but efficacy of the 4-weekly schedule was significantly (p=0.04) greater than once-weekly, a prior hypothesis.

The researchers concluded that the small (1-5%) survival benefit of adjuvant chemotherapy sufficiently outweighed the inconvenience and cost for high-risk and younger patients (under 70 years).

Reference: Gray RG, Barnwell J, Hills R, McConkey C, et al. QUASAR: A randomized study of adjuvant chemotherapy (CT) vs observation including 3258 colorectal cancer patients. Proceedings from the 40th annual meeting of the American Society of Clinical Oncology held in New Orleans LA, June 5-8, 2004; Abstract #3501.