Plasmablastic Lymphoma Versus EBV-Positive Myeloma

Excerpt

Hematolymphoid neoplasms with plasmablastic lymphoma (PBL) and plamablastic/anaplastic myeloma (PBM) show significant morphological and/or immunophenotypic overlap which may make it very difficult for pathologists to make a definite and specific histopathological diagnosis [1]. Features such as renal dysfunction, significant paraprotein, osteolytic bony lesions, hypercalcemia and diffuse bone marrow involvement favor a diagnosis of PBM. In contrast, EBER expression in neoplastic cells, HIV coinfection and high proliferative index support a diagnosis of PBL. When myeloma-defining signs are incomplete or absent, the presence of oropharyngeal soft tissue lesion or lymphadenopathy favor a diagnosis of PBL, regardless of bone marrow disease. The distinction is very important as the treatment of these entities differ remarkably. PBL is an aggressive disease with relapsing clinical course and has higher rates of disease progression and fatality despite use of state of the art treatment modalities. Current guidelines recommend intensive regimens such as EPOCH (infusional etoposide, vincristine, doxorubicin with bolus cyclophosphamide and prednisolone) and Hyper-CVAD (hyperfractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone alternating with methotrexate and cytarabine). On the other hand, myeloma is managed with Bortezomib-based regimens followed by autologous stem cell transplantation (ASCT). Despite extensive work-up, few cases remain to be classified into any of the two categories and thus are labelled as Indeterminate [2, 3]. We present one such case with overlapping features thereby making the diagnosis very intriguing. …