title: Classical Hodgkin lymphoma masquerading as chronic recurrent multifocal osteomyelitis: a case report.
abstract: BACKGROUND
  Hodgkin lymphoma is a hematologic malignancy usually confined to lymphatic structures and commonly associated with constitutional symptoms. Bony involvement and musculoskeletal symptoms are uncommon and typically seen in advanced disease. In this case, we report an unusual presentation of classical Hodgkin lymphoma and highlight diagnostic challenges leading to the misdiagnosis and treatment as chronic recurrent multifocal osteomyelitis.
  
  
  METHODS
  A 38-year-old white man presented with lower extremity musculoskeletal pain. Imaging studies revealed multifocal lytic and sclerotic osseous axial lesions. Multiple core needle bone marrow and excisional lymph node biopsies were non-diagnostic. Having met the criteria, a tentative diagnosis of chronic recurrent multifocal osteomyelitis was given. He was treated with non-steroidal anti-inflammatory medications with partial clinical response but had persistent symptoms. A second medical opinion was pursued. An open bone marrow biopsy was performed and yielded a diagnosis of classical Hodgkin lymphoma after 13 months of diagnostic uncertainty. A chemotherapy regimen of doxorubicin, bleomycin, vinblastine, and dacarbazine was instituted with complete symptomatic and radiologic response.
  
  
  CONCLUSIONS
  This case illustrates diagnostic difficulties of a musculoskeletal presentation of Hodgkin lymphoma, challenges of non-diagnostic bone marrow and lymph node biopsies, and resultant diagnostic delays in delivering a potentially curative therapy. Had the additional open bone marrow biopsy not been performed, the diagnosis and treatment of Hodgkin lymphoma would have been missed.
authors.affiliation: Division of Internal Medicine, Mayo Clinic, Phoenix, AZ, USA. pham.michael@mayo.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Pham
authors.affiliation: Division of Internal Medicine, Mayo Clinic, Phoenix, AZ, USA.
authors.forename: Steven
authors.initials: S
authors.lastname: Ressler
authors.affiliation: Division of Hematology and Oncology, Mayo Clinic, Phoenix, AZ, USA.
authors.forename: Allison
authors.initials: A
authors.lastname: Rosenthal
authors.affiliation: Division of Hematopathology, Mayo Clinic, Phoenix, AZ, USA.
authors.forename: Katalin
authors.initials: K
authors.lastname: Kelemen
mesh_terms: D000328:Adult; D001706:Biopsy; D001853:Bone Marrow / Q000473:pathology; D019046:Bone Marrow Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003951:Diagnostic Errors; D006689:Hodgkin Disease / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D008297:Male; D010019:Osteomyelitis / Q000175:diagnosis* / Q000473:pathology
keywords: CRMO; Chronic recurrent multifocal osteomyelitis; Classical Hodgkin lymphoma; Osseous lymphoma