Reed-Sternberg Cells : CD30
Immunophenotype of Reed-Sternberg (RS) Cells: The immunophenotype of diagnostic Reed-Sternberg (RS) cells and variants is constant across the four subtypes of classic Hodgkin lymphoma (cHL) despite their morphologic differences. Since RS cells make up only 0.1% to 0.2% of all cells in the involved tissues and are surrounded by a reactive inflammatory infiltrate, interpretation of immunostains can be quite challenging. RS cells and variants express activation-associated antigens such as CD30, CD25, CD40, CD71, and HLA-DR. They are negative for CD45 and show variable expression of lineage-specific markers as discussed in subsequent slides. CD30: CD30 belongs to the TNF-nerve growth factor receptor family and is expressed by RS cells and variants in more than 90% of cHL cases. There is strong cytoplasmic and membranous staining with dot-like accentuation of Golgi in the perinuclear zone. The LP cells of nodular lymphocyte-predominant Hodgkin lymphoma are CD30 negative but may rarely show weak, heterogenous staining. In reactive lymph nodes, CD30 positivity is often seen in perifollicular blasts. This should not be interpreted as interfollicular Hodgkin lymphoma. Other CD30-positive neoplasms include: anaplastic large cell lymphoma, a subset of peripheral T-cell lymphomas, lymphomatoid papulosis, some large B-cell lymphomas, and embryonal carcinoma.