Analyzing qualitatively and quantitatively genetic alterations with an efficient, simple and cost-effective test from blood samples could optimize therapeutic decision-making and personalized cancer care. Cell-free DNA (ccfDNA) levels in the plasma of CRC patients are significantly higher than in healthy patients. These levels decrease progressively in tumor-free patients during the follow-up period and increase in patients with recurrence or metastasis. In the near future, the detection of circulating DNA (ccfDNA) could therefore represent a technology breakthrough for diagnosis, prognosis, detection of tumor growth and cancer patient follow up.