Adjuvant Chemotherapy of Stage III Colon Cancer

Over the past two decades there have been notable advances in our understanding of what constitutes optimal adjuvant chemotherapy in patients with stage III colon cancer. Retrospective analyses of stratification by nodal status, T stage, and disease grade have shown marked differences in survival among patients with stage III disease, indicating the need for prospective stratification in clinical trials of adjuvant therapy. Similarly, analysis of the effects of such genetic/biologic properties as 18q loss of heterozygosity and microsatellite instability has shown marked differences in survival outcome with adjuvant therapy, prompting incorporation of investigation of potential prognostic markers in clinical trials. Recent randomized trials in stage III disease have shown that oxaliplatin combined with 5-fluorouracil (5-FU) and leucovorin (FOLFOX) is superior to the infusional leucovorin/5-FU (LV5FU2) regimen, that oral capecitabine is at least equivalent to bolus 5-FU/LV, and that irinotecan and 5-FU/LV (IFL) is not superior to bolus 5-FU/LV. Ongoing studies are likely to provide information that will markedly improve the ability to select optimal adjuvant therapy for individual patients.