Adjuvant Therapy for Stage II Colon Cancer: A Systematic Review From the Cancer Care Ontario Program in Evidence-Based Care’s Gastrointestinal Cancer Disease Site Group

Purpose To develop a systematic review that would address the following question: Should patients with stage II colon cancer receive adjuvant therapy? Methods A systematic review was undertaken to locate randomized controlled trials comparing adjuvant therapy to observation. Results Thirty-seven trials and 11 meta-analyses were included. The evidence for stage II colon cancer comes primarily from a trial of fluorouracil plus levamisole and a meta-analysis of 1,016 patients comparing fluorouracil plus folinic acid versus observation. Neither detected an improvement in disease-free or overall survival for adjuvant therapy. A recent pooled analysis of data from seven trials observed a benefit for adjuvant therapy in a multivariate analysis for both disease-free and overall survival. The disease-free survival benefits appeared to extend to stage II patients; however, no P values were provided. A meta-analysis of chemotherapy by portal vein infusion has also shown a benefit in disease-free and overall survival...