Somatic mutation profiling in ovarian Brenner and associated mucinous tumors.

e16585 Background: Benign ovarian Brenner tumors are often associated with mucinous cystadenomas (MCA) or mucinous borderline tumors (MBT) and hypothesized to share a histogenic origin and progression, yet limited molecular characterization has been conducted that might support this. Here, we describe targeted next generation sequencing of Brenner and ipsilateral mucinous tumors to identify molecular mechanisms linking these tumor types which may contribute to pathogenic progression. Methods: DNA from histologically diagnosed tumor FFPE samples (7 Brenner, 3 MCA, and 2 MBT (including 4 sets of paired samples)) was sequenced using a 358-gene next-generation sequencing assay. Sequenced samples were subjected to an in-house bioinformatic pipeline, partially annotated using SnpEff/SnpSift, and interpreted by mapping high/medium impact variants to an in-house manually curated clinical knowledgebase. Variant calls were compared within tumor groups to assess somatic mutation profiles. Results: 213 different high...