Diagnosis Of Classic Hodgkin Lymphoma On Bone Marrow Biopsy

Classic Hodgkin lymphoma (cHL) is a malignant B cell neoplasm that primarily affects lymph nodes, with potential to spread to extranodal sites, and involves virtually any organ system - lung, liver, bone and bone marrow. Primary extranodal presentation is uncommon and primary bone marrow involvement by cHL is very rare, usually occurring in HIV positive patients and is typically EBV-associated. Here, we summarise clinical and pathological findings of 14 cases of newly diagnosed cHL in bone marrow that were discussed at the bone marrow workshop of the 19th European Association for Haematopathology (EAHP)/Society of Hematopathology (SH) meeting held in Edinburgh in 2018. In contrast to the literature, workshop cHL cases occurred in HIV negative patients and only half of them were EBV positive. Diagnosis was hampered by the absence of specific clinical findings at presentation that otherwise might have raised concern for cHL. Moreover, on microscopic evaluation typical Hodgkin and Reed Sternberg cells were few and scattered in a mixed inflammatory and/or fibrotic background. Lastly, the concurrence with inflammatory diseases and/or other haematologic malignancies have complicated the diagnosis and the therapeutic approach to such patients.