Image Description
T-cell Markers in Reed-Sternberg (RS) Cells: Like B-cell markers, the expression of T-cell markers by RS cells is weak and inconsistent. Immunoreactivity for CD3, CD4, CD45RO, and CD43 is seen in RS cells in a small percentage of cases. Rare cases diagnosed as classic Hodgkin lymphoma (cHL) and strongly expressing T-cell markers do indeed carry T cell receptor gene rearrangements and are of T cell derivation.
Since RS cells are often surrounded by mature T-cells, the interpretation of T-cell markers can be challenging. This image shows several CD3-negative Hodgkin cells.
About 10% to 20% of cHL cases show heterogenous and weak expression of cytotoxic markers, including TIA-1, granzyme B, or perforin. Diffuse strong immunoreactivity for multiple T-cell markers may indicate a peripheral T-cell lymphoma.
About the Disease
Classic Hodgkin lymphoma (cHL) is an uncommon malignant neoplasm of germinal-center B-cell origin that is primarily seen in young adults and, less commonly, in elderly patients. It usually arises in a single node or group of nodes and shows orderly spread to contiguous lymphoid tissues. The neoplastic cells - known as Hodgkin and Reed-Sternberg cells - make up only about 1% of all the cells in the involved lymph node or tissue. They express cell surface CD30 antigen and are present in a microenvironment rich in immune effectors cells. Four histologic subtypes are recognized in the current classification - nodular sclerosis, mixed cellularity, lymphocyte-rich, and lymphocyte-depleted. In about 5% of cases, a subtype cannot be specified due to insufficient material for a complete analysis. The prevalence of Epstein-Barr virus and its role in the pathogenesis depends upon the subtype. cHL is highly sensitive to radiation and chemotherapy and is characterized by a high cure rate, even in advanced stages. Several novel therapies targeting specific molecular pathways have been developed to treat refractory cases. The comments accompanying the images have been derived from the following sources: References:Jaffe, E. S. et al (2017). Hematopathology - Second Edition. Philadelphia, PA. Elsevier. Goldblum, J. R. et al (2018). Rosai and Ackerman's Surgical Pathology - 11th Edition. Philadelphia, PA. Elsevier. Kumar, V., Abbas, A. K., & Aster, J. C. (2021). Robbins and Cotran Pathologic Basis of Disease - Tenth Edition. Philadelphia, PA. Elsevier. Connors, J. M. et al. Hodgkin Lymphoma. Nature Reviews. Disease Primers (2020) 6:61. Kuppers R, Engert A, & Hansmann M. Hodgkin Lymphoma. J Clin Invest. 2012; 122(10):3439-3447.