When combined methylation with FIT, KRAS and m3, respectively, the AUC values were 0.803, 0.824 and 0.903 in all patients (Figures 3J, M, P), respectively; For stage I CRC, the values were 0.779, 0.829 and 0.909 (Figures 3K, N, Q), which were 0.814, 0.811 and 0.886 in advanced CRC once combined methylation with FIT, KRAS and m3 (Figures 3L, O, R). The gene discussed is KRAS; the disease is colorectal carcinoma.