A rare case of double primary lung adenocarcinomas with uncommon complex EGFR G719X and S768I mutations and pleomorphic carcinoma.

Epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI)-targeted therapy has emerged as a viable treatment for patients with advanced non-small cell lung cancer with common EGFR mutations. The uncommon G719X and S768I mutations can co-occur as complex mutations in the same tumor. Here we report a case of a 72-year-old male patient with double lung carcinoma, with G719X and S768I complex mutations detected in the right upper lung lobe along with brain metastases.

Fatal limbic encephalitis as paraneoplastic neurological syndrome in a patient with lung adenocarcinoma positive for antiamphiphysin antibody after durvalumab treatment.

A 69-year-old Japanese male with advanced lung adenocarcinoma developed neurological symptoms after chemoradiotherapy and durvalumab maintenance therapy. He was positive for serum antiamphiphysin antibody, which is rarely seen in patients with lung adenocarcinoma. Additionally, his brain magnetic resonance images showed limbic encephalitis which led to the diagnosis of classic paraneoplastic neurological syndrome (PNS).