title: A case of Castleman's disease that presented as a retroperitoneal mass.
abstract: BACKGROUND
  A 35-year -old man presented to a local emergency room with acute left-flank pain and a medical history of nephrolithiasis. There were no aggravating or relieving factors for the left-flank pain and no other presenting symptoms, and the physical examination was unremarkable.
  
  
  METHODS
  Complete blood count, urinalysis, serum tumor markers, scrotal ultrasonography, CT scan of the abdomen (with and without contrast), MRI of the abdomen.
  
  
  METHODS
  Unicentric Castleman's disease (hyaline-vascular type).
  
  
  RESULTS
  Surgical exploration and excision. Pathologic and immunohistochemical work-up confirmed the diagnosis. CT scan after 7 months was normal with no evidence of recurrence.
authors.affiliation: Department of Surgery, Division of Urology, Memorial Sloan Kettering Cancer Center, New York, NY 10021, USA.
authors.forename: Kinjal
authors.initials: K
authors.lastname: Vora
authors.forename: Atreya
authors.initials: A
authors.lastname: Dash
authors.forename: Ariadne
authors.initials: A
authors.lastname: Bach
authors.forename: Anuradha
authors.initials: A
authors.lastname: Gopalan
authors.forename: Paul
authors.initials: P
authors.lastname: Russo
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D005871:Castleman Disease / Q000175:diagnosis* / Q000601:surgery*; D003937:Diagnosis, Differential; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D008297:Male; D012186:Retroperitoneal Neoplasms / Q000175:diagnosis* / Q000601:surgery*; D018570:Risk Assessment; D014057:Tomography, X-Ray Computed