Primary Mediastinal (Thymic) Large B-cell Lymphoma
Primary mediastinal large B-cell lymphoma (PMBL) is a large cell lymphoma of thymic medullary B-cell origin that exhibits clinicopathologic and molecular features that are more similar to classical Hodgkin lymphoma (CHL) than conventional diffuse large B-cell lymphoma (DLBCL). PMBL typically occurs in younger patients, shows a female predominance, and demonstrates characteristic genetic and immunophenotypic features related to activation of the NF-KB and JAK-STAT pathways. In addition, PMBL shows frequent structural alterations of chromosome 9p24 leading to upregulation of the immunoregulatory proteins PD-L1 and PD-L2. Due to these unique features, PMBL is considered as a distinct diagnostic category within the World Health Organization (WHO) Classification of Tumors of Hematopoietic and Lymphoid Tissues.
PMBL comprises approximately 2–4% of incident non-Hodgkin...
References and Further Reading
- Chapuy, B. et al. (2018). Comprehensive Genomic analysis of primary mediastinal B-cell lymphoma (abstract). American society of hematology annual meeting. San Diego.Google Scholar
- Swerdlow, S. H., et al. (2017). WHO classification of tumours of haematopoietic and lymphoid tissues. World Health Organization classification of tumours of haematopoietic and lymphoid tissue 4th. Geneva. http://publications.iarc.fr/Book-And-Report-Series/Who-Iarc-Classification-Of-Tumours/Who-Classification-Of-Tumours-Of-Haematopoietic-And-Lymphoid-Tissues-2017.