MP29-13 IMPROVING RENAL NEEDLE-BIOPSY ACCURRACY WITH RCC-SPECIFIC DNA METHYLATION MARKERS

Abstract

You have accessJournal of UrologyKidney Cancer: Basic Research II1 Apr 2014MP29-13 IMPROVING RENAL NEEDLE-BIOPSY ACCURRACY WITH RCC-SPECIFIC DNA METHYLATION MARKERS Mehrdad Alemozaffar, Clayton Coolings, Sameer Chopra, Sumeet Syan, Brian Hu, Inderbir Gill, and Gangning Liang Mehrdad AlemozaffarMehrdad Alemozaffar More articles by this author , Clayton CoolingsClayton Coolings More articles by this author , Sameer ChopraSameer Chopra More articles by this author , Sumeet SyanSumeet Syan More articles by this author , Brian HuBrian Hu More articles by this author , Inderbir GillInderbir Gill More articles by this author , and Gangning LiangGangning Liang More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.755AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The detection of small renal masses (SRMs) <4cm in size have risen given the widespread use of abdominal imaging. 20-30% of SRMs are benign and workup and management remains controversial with advocates for biopsy, surveillance, or surgical treatment. Thus, accurate characterization of SRMs is needed to determine treatment. Needle biopsy of SRMs have high false negative rates on standard microscopic examination (10–20%) since small amounts of tissue are sometimes obtained. We aimed to identify epigenetic markers to improve the diagnostic value of renal needle biopsies. METHODS Through an IRB approved protocol, needle biopsies were obtained ex-vivo following partial nephrectomy for 100 patients with SRMs. Each lesion underwent 3 pairs of biopsies: 2 from tumor regions and 1 from adjacent normal tissue; one was examined and other was used for DNA extraction. The methylation levels of these samples at select CpG dinucleotides throughout the genome were detected using the Infinium 450K array technology. To elucidate tissue-specific DNA methylation markers, these biological values were then compared to Infinium 450K data derived from 300 categorized renal samples from The Cancer Genome Atlas (TCGA). RESULTS Sixty SRMs have been examined to date. We isolated 9,432 candidate markers of differential DNA methylation with average beta value difference between two sample groups is >0.4 (Figure 1). Current efforts have been made to create an algorithm that allows us to predict the type of tissue based on methylation markers. To date, the algorithm has shown to successfully predict normal and cancerous tissue at a sensitivity rate of 91% and 90%, respectively. CONCLUSIONS Preliminary results suggest significant differences in DNA methylation levels exist at specific sites in the human genome among normal and aberrant kidney tissues. It's likely these biomarkers can be used to distinguish tissue types. We are using statistical approaches to identify a panel of DNA methylation markers to improve predicting phenotype and develop an economically efficient method for distinguishing between benign and cancer tissues. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e309-e310 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Mehrdad Alemozaffar More articles by this author Clayton Coolings More articles by this author Sameer Chopra More articles by this author Sumeet Syan More articles by this author Brian Hu More articles by this author Inderbir Gill More articles by this author Gangning Liang More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...