EGAGenomicsAndrew Futrealhttps://ega-archive.org/dacs/EGAC00001000223EGAEGA DAC EGAC00001000223EGAafutreal@mdanderson.orgCancers are composed of populations of cells with distinct molecular and phenotypic features, a phenomenon termed intratumor heterogeneity (ITH). ITH in lung cancers has not been well studied. We applied multiregion whole-exome sequencing (WES) on 11 localized lung adenocarcinomas. All tumors showed clear evidence of ITH. On average, 76% of all mutations and 20 out of 21 known cancer gene mutations were identified in all regions of individual tumors, which suggested that single-region sequencing may be adequate to identify the majority of known cancer gene mutations in localized lung adenocarcinomas. With a median follow-up of 21 months after surgery, three patients have relapsed, and all three patients had significantly larger fractions of subclonal mutations in their primary tumors than patients without relapse. These data indicate that a larger subclonal mutation fraction may be associated with increased likelihood of postsurgical relapse in patients with localized lung adenocarcinomas.Intratumor heterogeneity in localized lung adenocarcinomas delineated by multiregion sequencing.Zhang Jianjun J, Fujimoto Junya J, Zhang Jianhua J, Wedge David C DC, Song Xingzhi X, Zhang Jiexin J, Seth Sahil S, Chow Chi-Wan CW, Cao Yu Y, Gumbs Curtis C, Gold Kathryn A KA, Kalhor Neda N, Little Latasha L, Mahadeshwar Harshad H, Moran Cesar C, Protopopov Alexei A, Sun Huandong H, Tang Jiabin J, Wu Xifeng X, Ye Yuanqing Y, William William N WN, Lee J Jack JJ, Heymach John V JV, Hong Waun Ki WK, Swisher Stephen S, Wistuba Ignacio I II, Futreal P Andrew PAfalseAndy FutrealData Access Committee EGAC00001000223EGAC00001000223960625301631EGAS00001001542EGAS00001000930EGAD00001001692EGAD00001000985EGAD00001000984