MP69-11 CARBONIC ANHYDRASE IX ASSAY: A PARADIGM SHIFT IN DIAGNOSIS OF MALIGNANT CYSTIC RENAL LESIONS.

Abstract

You have accessJournal of UrologyKidney Cancer: Advanced II1 Apr 2015MP69-11 CARBONIC ANHYDRASE IX ASSAY: A PARADIGM SHIFT IN DIAGNOSIS OF MALIGNANT CYSTIC RENAL LESIONS. Himesh Gandhi, Appu Thomas, Balagopal T. Nair, and Vinoth Kumar Lakshmanan Himesh GandhiHimesh Gandhi More articles by this author , Appu ThomasAppu Thomas More articles by this author , Balagopal T. NairBalagopal T. Nair More articles by this author , and Vinoth Kumar LakshmananVinoth Kumar Lakshmanan More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.2515AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Cystic renal neoplasms are always decided radiologically using Bosniak classification system for renal cysts with many times the histopathology being benign in final report. Carbonic anhydrase IX (CA IX), a known marker for solid clear cell renal cell carcinoma (CCRCC) with good sensitivity and specificity, may be useful for differentiating benign versus malignant renal cystic lesions. The purpose of the study was to demonstrated the usefulness of CAIX in these confusing scenarios and to have a new tool for definitive diagnosis in such cases before contemplating radical surgery. METHODS A total of 22 patients were included in the study prospectively. Twelve patients diagnosed with Complex renal cysts-Bosniak type IIF, III, IV on Contrast-Enhanced Computerized Tomography (CECT) Abdomen and Pelvis undergoing partial/ radical nephrectomy were analysed. Intra-operatively,the aspirates were collected from complex cystic lesions and they were subjected to western blot analysis. Similarly, aspirates were collected from 10 patients with simple renal cysts undergoing surgery for other indications and their apirates were also subjected to western blotting to act as a control. Histopathological examination (HPE)of all operated complex cyst patients was done. Immunohistochemical (IHC) staining and scoring for both intensity and extent of positivity was done on the HPE slides. Scoring was done using a composite Score with score <2 was considered negative for CAIX expression while 2-3 was considerate moderate and > 3 considered strong resp and CA IX expression detected by western blotting and IHC staining were correlated. RESULTS Majority of the cysts in the study population belongs to Bosniak category III (85%). Diagnostic accuracy of the CA IX assay using Western Blotting was 83.33% and correlated with IHC staining with a negative predictive value 100%. Below table shows the correlation between IHC staining and CA IX expression using wetsern blotting. CONCLUSIONS Positive CA IX assay reflects presence of malignancy and those with negative test can be offered an surveillance thus obviating the need for immediate radical surgery as in this era renal preservation should be the main goal. CAIX should be considered a promising molecular marker to differentiate such complex cystic renal tumors (malignant versus benign cysts) and play role in definitive management. Correlation of CA IX expression profile using western blotting with IHC staining in complex cysts aspirates IHC* staining of HPE slides CA IX# positive CA IX # negative Total Positve (C.S.: >/= 2) 10 (83.33%) 2 (16.67%) 12 (100%) Negative (C.S.: < 2) 0 (0) 0 (0) 0 Total 10 (83.33%) 2 (16.67%) 12 (100%) *IHC- Immunohistochemical staining , # CA IX = Carboinc Anhydrase IX , $ C.S. = composite score (Intensity + Extent of staining on IHC). © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e870-e871 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Himesh Gandhi More articles by this author Appu Thomas More articles by this author Balagopal T. Nair More articles by this author Vinoth Kumar Lakshmanan More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...