Microscopic description and IHC:
The fine needle aspiration (FNA) shows polymorphic lymphoid population with scattered atypical (larger) cells. Flow cytometric analysis from the FNA specimen is non-contributory.
The resection specimen shows nodular hyperplasia of small lymphoid cells. admixed with scattered and clustered large atypical lymphoid cells with pleomorphic features and mononucleated or Reed-Sternberg-like cells. Eosinophiles are virtually absent. Nodular fibrotic bands are occasionally present.
The immunohistochemistry results show the large atypical cells are positive for CD45, CD20 and PAX5, and they are negative for the rest stains. CD20 shows both membrane and Golgi staining.
Flow cytometric analysis for the resection specimen is again non-contributory.
Discussion:
Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is an uncommon type of Hodgkin lymphoma (HL). Like the HL, it typically presents in young men with cervical or axillary adenopathy. However, it is typically not considered as a form a classic form of HL. It is composed of vague nodules of numerous reactive lymphocytes admixed with large popcorn-shaped Reed-Sternberg cells (RSC). Differing from classic RSC, the popcorn cells are CD15 and CD30 negative while positive for the B cell marker CD20. They may have follicular B cell origin and have potential for diffuse large B cells transformation (DLBCL) in 3 to 5% of the cases.
Clinically, NLPHL behaves indolently but recurrences are frequent. Treatment approaches range from conservative to aggressive and Rituximab maybe used.