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Examining the Role of Extrachromosomal DNA in 1,216 Lung Cancers

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June 12, 2025

Abstract

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-naïve lung cancer.

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