title: Erdheim-Chester Disease With Multiorgan Involvement, Following Polycythemia Vera: A Case Report.
abstract: Erdheim-Chester disease is a rare form of non-Langerhans cell histiocytosis characterized by the migration and infiltration of lipid-laden CD68, CD1a and S100 histiocytes to various target organs, which leads to the disruption of physiological tissue architecture and reactive fibrosis, and thus impairs organ function.We describe the first case of a patient with Erdheim-Chester disease with multiorgan involvement developed after 6 years from polycythemia vera diagnosis. During the follow-up, an abdominal ultrasound scan revealed the presence of dense, bilateral perinephric infiltration. A computed tomographic guided core biopsy was performed in order to identify the histological nature of this lesion, and a morphological analysis demonstrated the accumulation of foamy histiocytes surrounded by fibrosis. The BRAFV600E mutation was detected, and a diagnosis of Erdheim-Chester disease was made.The extreme rarity of Erdheim-Chester disease strongly suggests the existence of potentially common element(s) that may have contributed to the pathogenesis of both disorders. Obviously, further studies are needed to clarify the mutual roles and effects of JAK2 and BRAF mutations in this patient, as well as their possible therapeutic implications.
authors.affiliation: From the Oncohematology Division, IRCCS Ca' Granda - Maggiore Policlinico Hospital Foundation, and University of Milan (AI, DC, NO, PB, AC); Oncohematology Unit of the Elderly, IRCCS Ca' Granda - Maggiore Policlinico Hospital Foundation (AI); Unit of Medicine and Clinical Immunology, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University (LD, GC); Unit of Pathology, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University (CD); and Hematopathology Service, Division of Pathology, Department of Pathophysiology and Transplantation, University of Milan and IRCCS Ca' Granda - Maggiore Policlinico Hospital Foundation, Milan, Italy (UG).
authors.forename: Alessandra
authors.initials: A
authors.lastname: Iurlo
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Dagna
authors.forename: Daniele
authors.initials: D
authors.lastname: Cattaneo
authors.forename: Nicola
authors.initials: N
authors.lastname: Orofino
authors.forename: Paola
authors.initials: P
authors.lastname: Bianchi
authors.forename: Giulio
authors.initials: G
authors.lastname: Cavalli
authors.forename: Claudio
authors.initials: C
authors.lastname: Doglioni
authors.forename: Umberto
authors.initials: U
authors.lastname: Gianelli
authors.forename: Agostino
authors.initials: A
authors.lastname: Cortelezzi
mesh_terms: D000368:Aged; D001853:Bone Marrow / Q000473:pathology*; D031249:Erdheim-Chester Disease / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology*; D006331:Heart Diseases / Q000000981:diagnostic imaging / Q000209:etiology; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics; D007674:Kidney Diseases / Q000000981:diagnostic imaging / Q000209:etiology; D008297:Male; D011087:Polycythemia Vera / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology*; D049268:Positron-Emission Tomography; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography
chemical_list: C507924:JAK2 protein, human; D053614:Janus Kinase 2; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf