MP44-16 PREDICTORS OF NON-DIAGNOSTIC RENAL MASS BIOPSY

Abstract

You have accessJournal of UrologyKidney Cancer: Evaluation and Staging II1 Apr 2015MP44-16 PREDICTORS OF NON-DIAGNOSTIC RENAL MASS BIOPSY Michael Blute, Joel Prince, Eric Bultman, Louis Hinshaw, Anna Drewry, Sara Best, Fred T. Lee, Timothy Ziemlewicz, Meghan Lubner, Fangfang Shi, Stephen Y. Nakada, and E. Jason Abel Michael BluteMichael Blute More articles by this author , Joel PrinceJoel Prince More articles by this author , Eric BultmanEric Bultman More articles by this author , Louis HinshawLouis Hinshaw More articles by this author , Anna DrewryAnna Drewry More articles by this author , Sara BestSara Best More articles by this author , Fred T. LeeFred T. Lee More articles by this author , Timothy ZiemlewiczTimothy Ziemlewicz More articles by this author , Meghan LubnerMeghan Lubner More articles by this author , Fangfang ShiFangfang Shi More articles by this author , Stephen Y. NakadaStephen Y. Nakada More articles by this author , and E. Jason AbelE. Jason Abel More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1558AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Percutaneous renal mass biopsy (RMB) may be used to guide treatment decisions in small renal masses (SRM). However, approximately 15% of patients receive no benefit from RMB because findings are non-diagnostic. The objective of this study is to identify patient and tumor characteristic s that are associated non-diagnostic RMB. METHODS After IRB approval, data were reviewed for all RMB for masses ≤7cm from 2000 to 2014. Univariable and multivariable analysis was performed to identify predictors of indeterminate RMB including: imaging modality, type of biopsy, laterality, proximity to adjacent organs, tumor diameter, presence of radiologic enhancement, fat, calcification, necrosis, or cystic features, position within the kidney, body mass index, and skin to tumor distance. RESULTS In 83/565 (14.7%) overall and 72/413 (17.4%) with SRM ≤4cm, the biopsy findings were non-diagnostic. There were no differences in age, BMI, Charlson comorbidity score, or gender between diagnostic and non-diagnostic biopsy patient cohorts. Independent predictors of non-diagnostic biopsy overall included: cystic features, radiologic enhancement <20HU, tumor diameter, and skin-to-tumor distance (table). A total of 83 masses were classified as cystic, including 4/1/10/18 Bosniak category 2/2f/3/4 lesions. The non-diagnostic rate for RMB of cystic masses was 39.8%. Of 38 tumors with ≤20HU enhancement, non-diagnostic findings were noted in 16 (42.1%) including 9 pseudo-enhancing and 7 non-enhancing masses. Median skin-to-tumor distance was 10 cm (IQR 8.5 cm – 11 cm). Among 52 tumors with a skin-to-tumor distance ≥13 cm, 14 (26.9%) of biopsies were non-diagnostic. In patients with initial non-diagnostic biopsy, repeat biopsy non-diagnostic rate was not different from initial biopsy, 20.8% vs. 14.7%, (p=0.38). There was no there was no association between radiologist or pathologist experience and non-diagnostic rate, (p=0.76, 0.67). In 462 procedures where a resident or fellow was involved, there was no difference in non-diagnostic rate, p=0.80. In 7/565 (1.2%) patients, hospital admission was required after RMB for biopsy complications. CONCLUSIONS Non-diagnostic RMB is more common in masses that are cystic, have radiographic enhancement ≤20 HU, diameter ≤4 cm, or skin to tumor distance of ≥13 cm. These criteria can be used to improve patient selection for RMB. Multivariate Analysis of 413 renal masses >= 4cm for predictors of non-diagnostic biopsy Variable OR (95% CI) p-value Axial diameter per cm 0.59 (0.39-0.90) 0.01 Cystic features 4.85 (2.42-9.72) <0.0001 Radiographic enhancement <= 20HU 3.57 (1.49-8.52) 0.004 Skin to tumor distance >= 13cm 2.62 (1.17-5.85) 0.02 © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e532-e533 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Michael Blute More articles by this author Joel Prince More articles by this author Eric Bultman More articles by this author Louis Hinshaw More articles by this author Anna Drewry More articles by this author Sara Best More articles by this author Fred T. Lee More articles by this author Timothy Ziemlewicz More articles by this author Meghan Lubner More articles by this author Fangfang Shi More articles by this author Stephen Y. Nakada More articles by this author E. Jason Abel More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...