The majority of RCCs occur within the 7th decade of life, uncommonly arising in adults ≤46years. We reviewed the clinicopathologic features of early-onset renal cell carcinoma (RCC) and evaluated the role of immunohistochemistry (IHC) in potentially identifying diagnoses of newly recognized RCC subtypes that may have been previously misclassified. A retrospective review was performed from 2011-2016 for cases of RCC. Early-onset RCC was defined as ≤46years of age. Clinicopathologic findings and hematoxylin and eosin (H&E) slides were reviewed on early-onset RCC patients. IHC was performed on all cases previously diagnosed as unclassified or papillary. Clinicopathologic findings were compared to a control group of RCC patients >46years over the same time period. We identified 98/598 (16.4%) early-onset RCCs. The median age in the early-onset RCC and control group was 38.4 and 62.8years, respectively. The early-onset RCC group contained 33/96(34.3%) females and 63/96(65.6%) males, including 52/96(54.2%) Caucasians, 39/96(40.6%) African Americans, 4/96(4.2%) Hispanics, and 1/96(1%) Asian. Non-Caucasians were significantly more likely to develop early-onset RCC (P=.004). Early-onset RCCs included 52% clear cell, 28.6% papillary, 8.2% unclassified, 5.1% chromophobe, 3.1% clear cell papillary(CCP), and 3 other rare tumors. Six unclassified and 26 papillary RCCs had tissue available for IHC. 2/6(33.3%) unclassified RCCs were reclassified (1 CCP, 1 Xp11 translocation). 1/26(3.8%) papillary RCCs was reclassified as CCP. Early-onset RCCs were more likely to occur in non-Caucasians (P=.004), be lower stage (P=.03), and undergo partial nephrectomy (P=.002). Few unclassified and papillary tumors were reclassified with IHC.
Human pathology. 2017 Nov 10 [Epub ahead of print]
Tyler Clemmensen, Andres Matoso, Tiffany Graham, Win Shun Lai, Soroush Rais-Bahrami, Jennifer Gordetsky
Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA., Department of Pathology, Hopkins Hospital, Baltimore, MD, USA., Department of Urology, University of Alabama at Birmingham, Birmingham, AL, USA., Department of Urology, University of Alabama at Birmingham, Birmingham, AL, USA; Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA., Department of Pathology, Hopkins Hospital, Baltimore, MD, USA; Department of Urology, University of Alabama at Birmingham, Birmingham, AL, USA. Electronic address: .