The current invention relates to the method to detect early stage pre-symptom cancer with enhanced accuracy. The claimed methods use anti-tumor agent to cause lysis of any existing cancer cells in a person, and causing release of genetic material from the lysed cancer cells into the blood stream of the person. The claimed methods further utilize a PCR method to amplify cancer gene in released generic material from a blood plasma sample of the person. The claimed methods further perform genetic sequencing on the blood plasma sample after PCR to identify existence of the cancer genes, thereby confirming existence of cancer.