The genomic landscape and evolution of endometrial carcinoma progression and abdominopelvic metastasis

Recent studies have detailed the genomic landscape of primary endometrial cancers, but their evolution into metastases has not been characterized. We performed whole-exome sequencing of 98 tumor biopsies including complex atypical hyperplasias, primary tumors, and paired abdominopelvic metastases to survey the evolutionary landscape of endometrial cancer. We expanded and reanalyzed TCGA-data, identifying novel recurrent alterations in primary tumors, including mutations in the estrogen receptor cofactor NRIP1 in 12% of patients. We found that likely driver events tended to be shared by primary and metastatic tissue-samples, with notable exceptions such as ARID1A mutations. Phylogenetic analyses indicated that the sampled metastases typically arose from a common ancestral subclone that was not detected in the primary tumor biopsy. These data demonstrate extensive genetic heterogeneity within endometrial cancers and relative homogeneity across metastatic sites.