Khandekar, A.; Hoang, P. H.; Luebeck, J.; Diaz-Gay, M.; Zhao, W.; McElderry, J. P.; Hartman, C.; Miraftab, M.; Lee, O. W.; Barnao, K. M.; Bergstrom, E. N.; Yang, Y.; Nowak, M. A.; Rothman, N.; Homer, R.; Yang, S.-R.; Lan, Q.; Wedge, D. C.; Yang, L.; Chanock, S. J.; Zhang, T.; Alexandrov, L. B.; Landi, M. T.

The role of extrachromosomal DNA (ecDNA) in lung cancer, particularly in subjects who never smoked (LCINS), remains unclear. Examination of 1,216 whole-genome-sequenced lung cancers identified ecDNA in 18.9% of patients. Enrichment of MDM2 and other oncogenes amplification via ecDNA possibly drives a LCINS subset. Tumors harboring ecDNA or other focal amplifications showed similarly poor survival. A strong association with whole-genome doubling suggests most ecDNA reflects genomic instability in treatment-naive lung cancer.