Primary Mediastinal B Cell Lymphoma: Diagnosis and Treatment Approach

Primary mediastinal B-cell lymphoma (PMBCL) is a distinct B-cell lymphoma, representing only 2-3% of non-Hodgkin lymphoma (NHL).However, diagnosis can be challenging; newer diagnostic tools are required to distinguish PMBCL from overlapping B-cell lymphomas.Dysregulation of various signalling pathways and alteration of the tumour microenvironment are implicated in the pathogenesis of PMBCL.Management is challenging due to the scarcity of prospective studies.The commonly used first line immunochemotherapy regimens are R-CHOP (cyclophosphamide, doxorubicin, vincristine, prednisolone, and rituximab) and DA-EPOCH R (dose adjusted etoposide, prednisolone, vincristine, cyclophosphamide, doxorubicin, and rituximab).End-of-treatment (EOT) fluorodeoxyglucose positron emission tomography (FDG PET) scans are the recommended imaging modality to assess response.About 10-30% of PMBCL patients may develop relapsed/refractory (RR).The most common approach for RR PMBCL is salvage immunochemotherapy followed by ASCT.Unfortunately, the outcome of RR PMBCL is relatively poor.Therefore, newer therapeutic agents are being developed and evaluated under clinical trials, including CAR-T (chimeric antigen receptor T) cell therapy.