Oncotype DX for colon cancer: Are we ready for prime time in personalized medicine?

Significant advances have been made in the treatment of patients with early-stage colon cancer during the last several decades. However, a substantial number of patients with early-stage disease will not be cured by surgery alone. Although adjuvant chemotherapy has been well accepted for the treatment of stage III disease, the precise role of adjuvant chemotherapy in stage II disease remains a subject of debate. Although patients with high-risk stage II disease derive significant benefit from adjuvant chemotherapy, it remains unclear whether patients with average or low-risk stage II disease should receive adjuvant therapy. Significant efforts have been made to develop molecular biomarkers to further define the subset of stage II disease patients who would derive a substantial benefit from adjuvant chemotherapy. Herein, we review the current status of molecular biomarker research in the treatment of colorectal cancer with respect to the specific role of the Oncotype DX gene expression profiling method in patients with stage II disease.