%0 Journal Article %T Is transformed small cell lung cancer (SCLC) different from de novo SCLC? %A Park, Cheol-Kyu %A Oh, In-Jae %A Kim, Young-Chul %J Translational Cancer Research %D 2019 %B 2019 %9 %! Is transformed small cell lung cancer (SCLC) different from de novo SCLC? %K %X Small cell lung cancer (SCLC) transformation is one of the mechanisms for acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors ( EGFR -TKIs) in non-small cell lung cancer (NSCLC) (1-5). Although two types of histology are commonly thought to be different diseases, Oser et al . suggested that both combined histology tumors and SCLC transformation are possible because the type II alveolar cells, which are the cells of origin of some EGFR -mutant adenocarcinomas (ADC), may be transformed into SCLC (1). SCLC transformation from ADC has been sometimes observed in EGFR -wild type lung cancers that lack other mutations (6,7) or during anaplastic lymphoma kinase ( ALK )-targeted therapy (8-10) and programed cell death-1 (PD-1) immunotherapy (11,12). In addition, SCLC transformation has sometimes been reported in cancers other than lung cancer probably as a result of frequent repeat biopsies (13,14). %U https://tcr.amegroups.org/article/view/28004 %V 8 %N 2 %P 346-349 %@ 2219-6803