Genomic mutation profiles of paired ovarian cancers (OC) across time.

5521Background: Prior studies demonstrate the clonal heterogeneity of ovarian tumors but do not address the relationship between genomic alteration profiles and treatment selection. We analyzed comprehensive genomic profiling (CGP) results from paired recurrent OC tumor samples to identify changes in somatic mutations over time. Methods: DNA from two or more FFPE tumor samples collected serially during the course of clinical care from 49 OC patients in the Clearity Foundation Data Repository was analyzed for genomic mutations (Mut), microsatellite instability (MSI), tumor mutation burden (TMB), and loss of heterozygosity (LOH) by hybrid-capture, next-generation sequencing of up to 315 genes (Foundation Medicine, Cambridge, MA). Genomic profiles were compared between samples from the same patient excluding sub-clonal mutations and genes/biomarkers not assessed across assays. 5 pairs were excluded due to poor quality metrics. Results: 22 sample pairs compared primary tumor to recurrence (PR) and 22 pairs co...