Colorectal cancer (CRC) originates in cells of the colon or rectum. CRC is the third most common cancer worldwide. Surgery, radiation and chemotherapy remained the mainstream care of treatment. CRC is one of the major disease problems in Nepal. Patients not only die of loco-regional disease but also due the recurrent disease. There is an urgent need for biomarkers that allow early detection of relapse in colorectal cancer. We here propose that one such biomarker may be Circulating Cell-free DNA (CCFDNA) measurement. Recently, circulating cell-free DNA has attracted considerable interest in the cancer biomarker field. Increased levels of CCFDNA have been observed in cancer patients as compared to healthy donors. In a developing country like Nepal, finding a cancer biomarker using high throughput technology is challenging due to financial and human resources reasons. In addition to that, biomarkers should be easily isolated and should have a clinical utility. CCFDNA can easily be isolated from the plasma of cancer patients indicating a promising candidate as a non-invasive biomarker of cancer. Measurement of CCFDNA over time may allow oncologists to detect and treat recurrence early enough to improve disease outcomes. However, it has not been evaluated whether monitoring CCFDNA has any diagnostic, predictive /prognostic utility in context of colorectal cancer patients from Nepal. In addition, KRAS mutation is one of the most  frequent molecular abnormalities in colorectal cancer. KRAS mutation presence in CCFDNA associates with shorter survival of CRC patients. This study will also evaluate KRAS mutation in CRC using CCFDNA.