Cancer Biomarkers are substances that act as indicators of the cancer site in the body. Usually biomarkers are computable indicators of the biological state in the body, a molecule that is unleashed by the tumor or in response to the presence of tumor. Biomarkers are used for the assessment of risk in cancer patients. They are specifically related with genetic mutations or epigenetic alterations that show a measurable way to find the tumor cells. The advantages of biomarkers are that they can be used as a diagnostic tool, and can also determine whether the tumor is localized or metastatic in nature. Cancer prognosis can be determined by biomarkers. Cancer recurrence is also being examined by the biomarkers.