Klin Onkol 2025; 38(6): 484-487. DOI: 10.48095/ccko2025484.
Background: Recently, there has been interest in the CT imaging characteristics of lung cancer positive for mesenchymal-epithelial transition (MET) exon14 skipping mutation. Herein, we present a patient with MET exon 14 skipping gene-positive lung adenocarcinoma associated with multiple ground-glass opacities (GGOs) in both lungs and metachronous contralateral lung adenocarcinoma. Case: A 67-year-old man was referred to our hospital due to abnormal finding on chest radiograph. A chest CT on admission revealed a mass in the right lung. A chest CT scan showed a mass in the middle lobe of the right lung, and numerous GGO nodules of various sizes in both lungs. The mass was resected and it was diagnosed as a MET exon 14 skipping gene-positive invasive adenocarcinoma. A GGO nodule resected at the same time was pathologically diagnosed as atypical adenomatous hyperplasia (AAH). A GGO nodule in the left lung that was present at the initial consultation grew in size on a CT scan performed 1 year and 4 months after the right lung resection, and was therefore resected. The nodule was pathologically diagnosed as a MET exon 14 skipping gene-negative invasive adenocarcinoma. Genetic testing for an AAH adjacent to the second adenocarcinoma was negative for the MET exon 14 skipping gene. Conclusion: The clinical course of this patient was interesting clinical information in terms of providing insight into the morphology, imaging findings, and origin of MET exon 14 skipping gene-positive adenocarcinoma.