Background. The role of adjuvant chemotherapy in patients with stage IIA colorectal cancer (CRC) remains questionable, since this treatment strategy does not lead to an increase in overall survival. However, if at least one unfavorable prognosis factor is present, postoperative chemotherapy is still recommended. Currently, the global oncology community recognizes that this approach is not reliable and has a low level of evidence. Thus, the search for new predictive factors that can become a reliable tool when deciding whether to prescribe or refuse adjuvant chemotherapy continues. Determination of circulating tumor DNA (ctDNA) is one of the most promising areas. The article presents current literature data on the possibility and feasibility of determining ctDNA in patients with stage IIA colorectal cancer, which will allow optimizing postoperative treatment tactics.
Conclusion. Today, the ctDNA determination has become an important prognostic marker, which in the future can influence the management strategy of cancer patients both in the direction of escalation and de-escalation of treatment, protect some patients from overtreatment and, conversely, accurately select patients for more intensive treatment options.

Keywords: circulating tumor DNA, colorectal cancer, adjuvant chemotherapy