EGFR and metastatic neoplasm: EGFR mutations (such as one INDEL p.K746_A750del), PIK3CA (such as p.E545K), RB1 (p.R320*) and TP53 mutations (such as p.T155I) were only shared between the liver metastatic tumor and CTCs; gain region in chromosome 8q contains the c-Myc gene; gain in chromosome 5p, which contains the telomerase reverse transcriptase (TERT) gene; chromosomal regions, including 3q29, 17q22, 17q25.3 and 20p13, had significant gain in all 19 CTCs of patients