Original ArticlesAre Sporadic Eosinophilic Solid and Cystic Renal Cell Carcinomas Characterized by Somatic Tuberous Sclerosis Gene Mutations?Parilla, Megan MD; Kadri, Sabah PhD; Patil, Sushant A. PhD; Ritterhouse, Lauren MD; Segal, Jeremy MD, PhD; Henriksen, Kammi J. MD; Antic, Tatjana MDAuthor Information Department of Pathology, University of Chicago, Chicago, IL Supported by the University of Chicago Faculty Diversity Career Advancement Grant. 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: Tatjana Antic, MD, Department of Pathology, The University of Chicago Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637 (e-mail: [email protected]). The American Journal of Surgical Pathology: July 2018 - Volume 42 - Issue 7 - p 911-917 doi: 10.1097/PAS.0000000000001067 Buy Metrics Abstract Eosinophilic solid and cystic renal cell carcinomas (ESC RCC) is a rare, unique tumor type not yet included in the World Health Organization classification of renal neoplasia. Separately, RCCs found in patients with tuberous sclerosis complex (TSC) have recently been categorized into 3 morphologic groups: RCC with a tubulopapillary architecture separated by smooth muscle stroma, chromophobe-like, and eosinophilic-microcytic type. The third classification has been identified in ∼11% of TSC-associated RCC and have histology identical to ESC RCCs. The sporadic form of ESC RCC, not associated with TSC, have only been characterized on the cytogenetic level and the full molecular underpinnings have yet to be examined. Using next-generation sequencing we present 2 cases of sporadic ESC RCC in patients without clinical features of tuberous sclerosis, which demonstrate pathogenic somatic TSC2 gene mutations. These mutations are without other alterations in any other genes associated with RCC, suggesting that sporadic ESC RCC may be characterized by somatic tuberous sclerosis gene mutations (TSC2). Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.