EML4 and pericardial effusion: Among them, EGFR T790M, EGFR E746_A750delELREA, EGFR L861Q, KRAS G12C, EML4-ALK (exon 18: exon 20) fusion, EML4-ALK (exon 20: exon 20) fusion, and ERBB2 Y772_A755dupYVMA were detected in both pericardial effusion-cfDNA and pericardial effusion-sDNA.