PIK3CA and neoplasm: High-frequency mutation genes detected in the three sample types were consistent with previous literature[21, 38], such as TP53, CCND1, PIK3CA, CDKN2A, ROS1, and ALK etc. TP53 had the highest frequency of mutations in tumor tissue, preoperative plasma, and postoperative plasma samples, with rates of 90.3%, 56.5%, and 28.0%, respectively.