Relapsed/refractory primary mediastinal large B-cell lymphoma: a structured review of epidemiology, treatment guidelines and real-world treatment practices.

Background

Primary mediastinal (thymic) large B-cell lymphoma (PMBCL) is an uncommon subtype of diffuse large B-cell lymphoma. Approximately 10-30% of patients experience refractory or relapsed PMBCL (rrPMBCL) after first-line therapy. Data and treatment guidelines for rrPMBCL are scarce, and management is based on clinical experience.

Methods

Two structured literature reviews were undertaken to determine the incidence, prevalence, and mortality rates associated with rrPMBCL, and to identify clinical practice guidelines and real-world patterns of care.

Results

Epidemiology studies included reported lymphomas (n = 1), non-Hodgkin lymphoma (n = 1), lymphoid neoplasm (n = 1), PMBCL (n = 6), and rrPMBCL (n = 1). Of 12 published treatment guidelines, only four provided recommendations for rrPMBCL. Sixteen studies provided data on real-world treatment patterns, but most were single-center studies with small patient numbers. Chemotherapy/immunochemotherapy, followed by high-dose treatment (HDT) and stem cell transplantation, was a mainstay of salvage therapy in most studies; real-world care generally followed treatment guidelines.

Conclusions

Salvage chemotherapy (often with rituximab and radiotherapy), followed by HDT and stem cell transplantation, appears to be the standard real-world treatment for rrPMBCL. However, large prospective and retrospective studies are warranted to improve our knowledge of real-world treatment patterns.