Abstract 47: Mutation in homologous recombination as a prognostic factor independent of TCGA molecular subtypes in endometrial cancer

Background: Endometrial cancers have been categorized into four genomic classes by The Cancer Genome Atlas Research Network (TCGA) with comprehensive genomic analysis. However, TCGA molecular subtypes are hard to utilize in clinic as the expensive cost and a simply version of POLE, TP53 genes cannot fully differentiate the four subtypes. Therefore, more convenient and reliable biomarkers need to be identified for clinical practice. Methods: Whole-exome sequencing and RNA sequencing data for 529 patients with endometrial carcinomas were downloaded from TCGA. Mutations in 62 genes of homologous recombination repair (HR) signaling were defined as HR mutation. Associations between HR mutation and survival and RNA expression were analyzed. Results: HR mutation was associated with a prolonged disease specific survival (DSS) (HR, 0.47; 95% CI, 0.28-0.79; P Conclusion: HR mutation was related with a favorable prognosis through increasing T cells signature. Identification of HR mutation by genomic profiling provides a potentially novel and convenient approach for endometrial cancer patients to predict the prognosis independent of TCGA four subtype classifications Citation Format: Luyang Zhao, Yibo Dai, Yuanjing Hu, Zhiqi Wang, Chengcheng Li, Guoqiang Wang, Jianliu Wang. Mutation in homologous recombination as a prognostic factor independent of TCGA molecular subtypes in endometrial cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 47.