title: Pediatric cystic nephromas: distinctive features and frequent DICER1 mutations.
abstract: Cystic nephromas (CNs) are uncommon benign renal neoplasms that present with a bimodal age distribution, affecting either infants/young children or adult females. Although differences between these age groups have been suggested, large studies of pediatric CN have not been conducted. As a result, the nomenclature and diagnostic criteria for these lesions remain controversial. In addition, the morphological overlap seen between CN and cystic partially differentiated nephroblastoma (CPDN) can result in diagnostic dilemmas. This study reviews the morphologic and radiographic features of 44 pediatric CN prospectively enrolled on a Children's Oncology Group protocol from 2007 to 2013. Although the typical multicystic architecture with thin septa described in adult CN was present in all of our pediatric cases, differences were also identified. We report distinctive features that add to the morphological spectrum of CN in children. Of the 44 cases, 16 had been previously analyzed and reported for DICER1 mutation, and either loss of function or missense mutations or both were identified in 15 of 16. In contrast, we analyzed 10 cases of adult CN, and all were negative for DICER1 mutations; similarly, 6 CPDNs previously analyzed and reported were negative for DICER1 mutations. Therefore, the clinical, morphological, and genetic differences between pediatric and adult CN, as well as between CN and CPDN, suggest that these 3 lesions represent distinct entities.
authors.affiliation: Department of Pathology and Laboratory Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago and Northwestern University Feinberg School of Medicine, Chicago, IL 60611. Electronic address: mcajaiba@luriechildrens.org.
authors.forename: Mariana M
authors.initials: MM
authors.lastname: Cajaiba
authors.affiliation: Department of Radiology, Washington University School of Medicine, St Louis, MO 63110.
authors.forename: Geetika
authors.initials: G
authors.lastname: Khanna
authors.affiliation: Departrment of Radiology, University of Michigan Health System, Ann Arbor, MI 48109.
authors.forename: Ethan A
authors.initials: EA
authors.lastname: Smith
authors.affiliation: Department of Pathology, Vanderbilt University Medical Center, Nashville, TN 37232.
authors.forename: Lan
authors.initials: L
authors.lastname: Gellert
authors.affiliation: Department of Biostatistics, University of Florida, Gainesville, FL 32611.
authors.forename: Yueh-Yun
authors.initials: YY
authors.lastname: Chi
authors.affiliation: Department of Pediatric Oncology, Children's Hospital Boston/Dana-Farber Cancer Institute, Boston, MA 02115.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Mullen
authors.affiliation: Department of Pathology, Children's National Medical Center, Washington, DC 20010.
authors.forename: Dana A
authors.initials: DA
authors.lastname: Hill
authors.affiliation: Division of Pediatric Oncology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229.
authors.forename: James I
authors.initials: JI
authors.lastname: Geller
authors.affiliation: Division of Pediatric Oncology, Children's National Medical Center, Washington, DC 20010.
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Dome
authors.affiliation: Department of Pathology and Laboratory Medicine, Ann & Robert H. Lurie Children's Hospital of Chicago and Northwestern University Feinberg School of Medicine, Chicago, IL 60611.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Perlman
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003560:Cysts / Q000473:pathology; D053487:DEAD-box RNA Helicases / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007680:Kidney Neoplasms / Q000235:genetics* / Q000473:pathology*; D008297:Male; D009154:Mutation; D043244:Ribonuclease III / Q000235:genetics*
chemical_list: C408087:DICER1 protein, human; D043244:Ribonuclease III; D053487:DEAD-box RNA Helicases
keywords: Cystic nephromas; DICER1; Pediatric renal tumors; Renal cystic lesions; Renal development