[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-456427-105":59,"doc-detail-456427-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","rosai-dorfman-disease-mimicking-testicular-malignancy-case-report","Rosai-Dorfman disease mimicking testicular malignancy - case report","","Rosai-Dorfman-Destombes disease (RDD) is a rare, typically benign histiocytic disorder that most often affects lymph nodes and can show extranodal disease in nearly half of patients. This report describes bilateral testicular RDD occurring three years after remission of extranodal marginal zone lymphoma of the lung, with imaging and clinical findings that mimicked malignancy. Bilateral orchiectomy demonstrated tan-yellow fleshy masses and histology confirmed RDD with emperipolesis and an S100+/CD68+/CD1a− phenotype. Testicular RDD is extremely uncommon, and recognition helps avoid unnecessary oncological treatment.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":35,"@type":76,"position":81},"https://docshare.wps.com/document/healthcare/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/rosai-dorfman-disease-mimicking-testicular-malignancy-case-report/456427/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/rosai-dorfman-disease-mimicking-testicular-malignancy-case-report/456427.png","ImageObject",300,407,{"name":92,"@type":93},"pop out","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-11-01","2026-09-30",true,{"@type":102,"interactionType":103,"userInteractionCount":39},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"Why was testicular RDD mistaken for malignancy in this case?","Question",{"text":112,"@type":113},"The patient developed progressive bilateral testicular enlargement, and ultrasound plus positron emission tomography/CT showed diffuse changes with metabolic activity suggestive of malignancy. The clinical and imaging overlap created diagnostic concern for recurrence of lymphoma.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"What histological and immunophenotypic findings confirmed Rosai-Dorfman disease?",{"text":117,"@type":113},"Bilateral orchiectomy showed tan-yellow fleshy masses infiltrating the testicular parenchyma. Histology confirmed RDD with emperipolesis, and immunohistochemistry demonstrated S100+ and CD68+ histiocytes negative for CD1a.",{"name":119,"@type":110,"acceptedAnswer":120},"How common is primary testicular Rosai-Dorfman disease?",{"text":121,"@type":113},"Primary testicular RDD is extremely rare, with only around 15 cases described in the literature to date.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},456427,1791101555,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":34,"category_name":35,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":39,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":19,"language":139,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":140,"faqs":141,"seo_title":142,"seo_description":67,"update_tm":143,"read_time":52,"preview_page_count":4},962090760408,"https://ap-avatar.wpscdn.com/davatar_085a072bc5b1113ac321206ff7593b45","Case report  \nRosai-Dorfman disease mimicking testicular malignancy in a patient with marginal zone lymphoma of the lung  \nEfrain Lee-Diaz,1 Victoria Claire Vaughan,2 Lian Zhang,3 Zenggang Pan,2 Francisco G La Rosa  2  \n1Universidad Peruana Cayetano Heredia, Lima, Peru 2Pathology, University of Colorado Anschutz Medical Campus School of Medicine, Aurora, Colorado, USA 3Pathology, UCHealth Highlands Ranch Hospital, Highlands Ranch, Colorado, USA  \nCorrespondence to  \nDr Francisco G La Rosa; Francisco. LaRosa@cuanschutz. edu  \nAccepted 11 December 2025  \n© BMJ Publishing Group Limited 2026. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ Group.  \nTo cite: Lee-Diaz E, Vaughan VC, Zhang L, et al. BMJ Case Rep 2026;19:e265657 . doi:10 . 1136/bcr-2025- 265657  \nSUMMARY  \nRosai-Dorfman-Destombes disease (RDD) is a rare, benign histiocytic disorder, most often involving lymph nodes but showing extranodal manifestations in nearly 50% of cases, particularly in the skin and upper respiratory tract. A hallmark histological feature is emperipolesis—large CD68+ and S100+ histiocytes containing intact inflammatory cells. Wereport a unique case of bilateral testicular RDD in aman with prior extranodal marginal zone lymphoma of the lungs. Three years after lymphoma remission, he presented with bilateral testicular enlargement. Ultrasound and positron emission tomography/ CT showed diffuse hypoechoic parenchyma with metabolic activity suggestive of malignancy.  \nBilateral orchiectomy revealed tan-yellow, fleshy masses infiltrating the testicular parenchyma. Histology confirmed RDD with emperipolesis and S100+/CD68+/CD1a− phenotype. Testicular RDD is extremely uncommon, with only ~15 cases described to date, and its association with haematological malignancy remains poorly understood. Recognition of this entity is essential to avoid unnecessary oncological treatment.  \nBACKGROUND  \nRosai-Dorfman-Destombes disease (RDD), originally described by Destombes in 1965 and later by Rosai and Dorfman in 1969, is a non-Langerhans histiocytic proliferation characterised by the accumulation of distinctive histiocytes within lymph node sinuses or extranodal tissues.1  \nRDD is now classified within group R histiocytoses according to the 2016 revised classification of histiocytoses and dendritic cell neoplasms.1 It is often indolent but rarely self-resolves completely, and most patients require at least limited therapy.2 3  \nThe pathogenesis of RDD involves activating mutations in the MAPK/ERK pathway (KRAS, NRAS, MAP2K1), which are found in approximately 40% of cases.1 4 5 Immune dysregulation and autoimmunity also play significant roles, and RDD can overlap with IgG4-related disease or occur in the setting of polyclonal hypergammaglobulinaemia.6–8 Familial forms associated with SLC29A3 mutations have been documented in children with systemic histiocytosis and syndromic features.9  \nExtranodal involvement occurs in up to 50% of patients, most frequently affecting the skin, upper airway and lungs, however nearly every organ can be involved, including the kidneys  \nand genitourinary tract.10 11 Testicular RDD remains exceedingly rare, with only ~15 cases described.2–4 6 7 10 12–19  \nTherapeutic approaches depend on clinical presentation. While many localised cases are surgically managed, systemic disease may require corticosteroids, radiation or targeted therapy with MEK inhibitors in those harbouring MAPK pathway mutations.3 20 Thalidomide or lenalidomide with corticosteroids is an emerging option for refractory or cutaneous disease.21–23  \nWe present a rare case of bilateral testicular RDD occurring 3 years after successful treatment of extranodal marginal zone lymphoma of the lung.24 The case illustrates the diagnostic challenge posed by its clinical and imaging overlap with malignancy.  \nCASE PRESENTATION  \nA man in his mid-60s with a history of extranodal marginal zone lymphoma of the lung, chronic obstru","cbCaiglLgv4fOuR3","https://ap.wps.com/l/cbCaiglLgv4fOuR3","pdf",1960208,"English","# SUMMARY\n# BACKGROUND\n# CASE PRESENTATION\n# INVESTIGATIONS\n# Case report figure and immunohistochemistry description","[{\"question\":\"Why was testicular RDD mistaken for malignancy in this case?\",\"answer\":\"The patient developed progressive bilateral testicular enlargement, and ultrasound plus positron emission tomography/CT showed diffuse changes with metabolic activity suggestive of malignancy. The clinical and imaging overlap created diagnostic concern for recurrence of lymphoma.\"},{\"question\":\"What histological and immunophenotypic findings confirmed Rosai-Dorfman disease?\",\"answer\":\"Bilateral orchiectomy showed tan-yellow fleshy masses infiltrating the testicular parenchyma. Histology confirmed RDD with emperipolesis, and immunohistochemistry demonstrated S100+ and CD68+ histiocytes negative for CD1a.\"},{\"question\":\"How common is primary testicular Rosai-Dorfman disease?\",\"answer\":\"Primary testicular RDD is extremely rare, with only around 15 cases described in the literature to date.\"}]","Rosai-Dorfman disease mimicking testicular malignancy - case report | PDF",1790745990]