PTCL : Lymphoepithelioid Variant (Lennert's)
Three histologic variants of PTCL, NOS, have been recognized : 1) Lymphoepithelioid variant (Lennert's Lymphoma), 2) T-zone variant, and 3) Follicular variant. These variants are rare and their prognostic significance is uncertain. Lymphoepithelioid variant is characterized by nodular or diffuse collections of pink epithelioid histiocytes creating a granulomatous appearance. The histiocytes may be abundant and obscure the neoplastic process. Majority of the neoplastic T-cells are small with only minimal nuclear irregularities. In addition, there may be some large cells, Reed-Sternberg-like cells, plasma cells, and eosinophils. The lymphoepithelioid variant tends to remain confined to the lymph node.