Moreover, the frequencies of mutated genes in plasma ctDNA of patients with CRC in our study were inconsistent with those in tissue DNA which had been reported in mutation database including The Cancer Genome Atlas.53, 54 Although the mutation frequency of APC gene in CRC tissue has been reported to be ~80%,53, 55 it revealed only 23.7% in our data (plasma), which was significantly lower frequency than that in tissue. The gene discussed is APC; the disease is colorectal carcinoma.