{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T16:59:53Z","timestamp":1780678793147,"version":"3.54.1"},"reference-count":14,"publisher":"S. Karger AG","issue":"1","license":[{"start":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T00:00:00Z","timestamp":1774828800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T00:00:00Z","timestamp":1774828800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Case Rep Oncol"],"abstract":"<jats:p>Introduction: The most effective TKI choice for NSCLC carrying non-classical compound mutations in EGFR remains unclear. The compound mutation in exon 18 G719A and exon 21 L861Q is rare, and experience with osimertinib is limited. Case Presentation: A 51-year-old male patient underwent surgery for T4N0 colon adenocarcinoma in 2015 and was followed without recurrence after eight cycles of adjuvant CapeOx, which was observed in 2025. A right lung nodule that remained stable for 7 years showed dimensional progression from 1 cm to 2 cm and metabolic progression from an SUVmax of 2.02 to 4.73. Wedge resection and IHC profiles were consistent with a diagnosis of second primary lung adenocarcinoma, and no malignancy was observed in the mediastinal lymph nodes. The patient, whose FFPE tissue NGS revealed a G719A + L861Q co-mutation and PD-L1 0%, was restaged to stage 4A (M1a) with pleural and paratracheal foci on postoperative PET-CT, and osimertinib 80 mg\/day was initiated. PET-CT performed at 3 months showed complete resolution of all FDG-enhancing target lesions, demonstrating a complete response. The response is ongoing at 7 months of follow-up, and the only side effect was a grade 1 acneiform rash. Conclusion: This case demonstrates that osimertinib can achieve an early, deep, and sustainable response in patients with a rare G719A\/L861Q co-mutation. Prospective evidence is necessary for rare EGFR subtypes.<\/jats:p>","DOI":"10.1159\/000551796","type":"journal-article","created":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T16:00:48Z","timestamp":1774886448000},"page":"639-646","source":"Crossref","is-referenced-by-count":0,"title":["Stage 4A Lung Adenocarcinoma with Rare EGFR Exon 21 L861Q and Exon 18 G719A Co-Mutations Showing Complete PET-CT Response to Osimertinib: A Case Report"],"prefix":"10.1159","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5916-6265","authenticated-orcid":false,"given":"Seray","family":"Saray","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tufan","family":"Y\u0131lmaz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hasan","family":"Bozkurt","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"127","published-online":{"date-parts":[[2026,3,30]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","DOI":"10.1016\/j.canep.2024.102693"},{"key":"ref2","doi-asserted-by":"publisher","DOI":"10.3390\/genes13081499"},{"key":"ref3","doi-asserted-by":"publisher","DOI":"10.5152\/TurkThoracJ.2022.21270"},{"key":"ref4","doi-asserted-by":"publisher","DOI":"10.1016\/j.jtocrr.2022.100459"},{"key":"ref5","doi-asserted-by":"publisher","DOI":"10.1016\/j.jtho.2024.03.016"},{"key":"ref6","doi-asserted-by":"publisher","DOI":"10.3389\/fonc.2020.01635"},{"key":"ref7","doi-asserted-by":"publisher","DOI":"10.1016\/S1470-2045(15)00026-1"},{"key":"ref8","doi-asserted-by":"publisher","DOI":"10.1016\/j.lungcan.2017.11.005"},{"key":"ref9","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa1913662"},{"key":"ref10","doi-asserted-by":"publisher","DOI":"10.21037\/tlcr-23-788"},{"key":"ref11","doi-asserted-by":"publisher","DOI":"10.1097\/JTO.0000000000000504"},{"key":"ref12","doi-asserted-by":"publisher","DOI":"10.18632\/oncotarget.26951"},{"key":"ref13","doi-asserted-by":"publisher","DOI":"10.1016\/j.jtho.2016.12.018"},{"key":"ref14","doi-asserted-by":"publisher","DOI":"10.1097\/JTO.0b013e3182781e35"}],"container-title":["Case Reports in Oncology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000551796","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,5]],"date-time":"2026-06-05T16:00:56Z","timestamp":1780675256000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000551796"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,30]]},"references-count":14,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,1,1]]}},"URL":"https:\/\/doi.org\/10.1159\/000551796","archive":["Portico"],"relation":{},"ISSN":["1662-6575"],"issn-type":[{"value":"1662-6575","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,30]]}}}