Primary mediastinal B-cell lymphoma

Primary mediastinal B-cell lymphoma is an established subtype of non-Hodgkin Lymphoma with distinguishable histopathological and clinical features. It characteristically presents with a bulky mediastinal mass and in a younger, predominantly female population. Advanced age, high LDH levels, and poor performance status are associated with poorer prognosis. Endobronchial ultrasound-guided transbronchial needle aspiration may be a valuable tool for establishing the diagnosis. At a molecular level, it has overlapping traits with nodular sclerosis classical Hodgkin Lymphoma. There is a variety of treatment options, with no standardized regimen. The use of rituximab combined with chemotherapy has correlated with good outcomes. The use of consolidative radiotherapy is controversial, with questionable benefit and established long-term toxicity, including secondary malignancy and cardiovascular disease. An FDG-PET scan is indicated when monitoring for response, because a residual mediastinal mass is commonly seen upon treatment completion but does not always indicate active disease. Relapse usually occurs within the first year, but overall survival is similar to that for diffuse large B-cell lymphoma.