Shedding Light on the Prognostic and Predictive Value of Circulating Tumor DNA for Management of Patients with Early-Stage Colon Cancer.

The management of early-stage colon cancer involves surgical resection of the primary tumor with or without chemotherapy, depending on pathological staging. The benefit of adjuvant chemotherapy for stage II and III colon cancer is approximately 5% and 15%, indicating the need for optimization for risk stratification and patient selection. Several studies have revealed that current clinicopathological factors lack precision. Circulating tumor DNA (ctDNA) is cell-free DNA originating from cancer cells and can be detected even in the absence of radiologically detectable disease among patients with colon cancer. Recent cohort studies revealed that ctDNA is one of the most significant prognostic factors for patients with early-stage colon cancer, surpassing pathological and clinical risk factors. Prospective cohort studies also suggest there may be a predictive role for ctDNA on the decision for consideration of adjuvant therapy. Currently, randomized clinical trials are enrolling to better define this role. In this review article, we review recent literature on ctDNA and its role in patients with colon cancer. We also elaborate on the future clinical utility of ctDNA in clinical practice and the unmet need for research to optimize currently available ctDNA assays.