case_images: PMC9035954_01
case_images: CT views of metastatic disease with large right pleural effusion (*), pleural thickening, and intra-abdominal adenopathy (white arrow) at diagnosis. CT, computed tomography.
case_images: cro-0015-0285-g01.jpg
case_images: PMC9035954_01_cro-0015-0285-g01.jpg
case_images: F1
case_images: A chest X-ray revealed a large right-sided pleural effusion, with subsequent computed tomography scan of the thorax, abdomen/pelvis confirming the presence of the pleural effusion and additional multiple lung nodules, extensive upper retroperitoneal lymphadenopathy, and small volume ascites (Fig. 1).
case_images: Schematic outlining the mutation of the atypical K757N mutation in relation to other common sensitizing mutations in EGFR-positive lung cancer.
case_images: cro-0015-0285-g02.jpg
case_images: PMC9035954_01_cro-0015-0285-g02.jpg
case_images: F2
case_images: Targeted next-generation sequencing (NGS) revealed the absence of KRAS and BRAF mutations but was positive for an exon 19 missense mutation where a lysine residue was substituted with asparagine at position 757 (K757N) at 49% allele frequency (Fig. 2).