Special ArticlesBest Practices Recommendations in the Application of Immunohistochemistry in the Kidney Tumors Report From the International Society of Urologic Pathology Consensus ConferenceReuter, Victor E. MD*; Argani, Pedram MD†; Zhou, Ming MD, PhD‡; Delahunt, Brett MD, FRCPA§ Members of the ISUP Immunohistochemistry in Diagnostic Urologic Pathology GroupAuthor Information *Department of Pathology, Memorial Sloan-Kettering Cancer Center ‡Department of Pathology, New York University, New York, NY †Departments of Pathology and Oncology, The Johns Hopkins Medical Institutions, Baltimore, MD §Department of Pathology and Molecular Medicine, University of Otago, Wellington, New Zealand Members of the ISUP Immunohistochemistry in Diagnostic Urologic Pathology Group: Mahul B. Amin, Jonathan I. Epstein, Thomas M. Ulbright, Peter A. Humphrey, Lars Egevad, Rodolfo Montironi, David Grignon, Kiril Trpkov, Antonio Lopez-Beltran, Daniel M. Berney, John R. Srigley, Satish K. Tickoo. Conflicts of Interest and Source of Funding: The authors have disclosed that they have no significant relationships with, or financial interest in, any commercial companies pertaining to this article. Correspondence: Victor E. Reuter, MD, Department of Pathology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021 (e-mail: [email protected]). The American Journal of Surgical Pathology: August 2014 - Volume 38 - Issue 8 - p e35-e49 doi: 10.1097/PAS.0000000000000258 Buy Metrics Abstract Primary renal neoplasms comprise multiple distinct entities, some of which are well understood and others that are not. It is not uncommon for some of these entities to have overlapping morphologic features. Their clinical behavior is varied, ranging from highly malignant to benign, and metastatic renal cell carcinoma oftentimes enters into the differential diagnosis of tumors of unknown primary. In this age of personalized medicine, identifying biomarkers that can better predict clinical outcome and response to therapy is a pressing need. In 2013 the International Society of Urological Pathology held a meeting in which best practices recommendations on the use of immunohistochemical markers in urologic malignancies were discussed. In this review we make recommendations regarding immunohistochemical markers that are best suited to aid in establishing a diagnosis of renal primary, panels of antibodies that are most useful in classifying renal tumors, and the current status of prognostic and predictive biomarkers. Although no prognostic or predictive marker and set of markers have yet to be validated, ongoing research suggests that this fact is likely to change in the near future. © 2014 by Lippincott Williams & Wilkins.