Primary cutaneous follicle center lymphoma with Hodgkin and Reed-Sternberg-like cells: a new histopathologic variant.

[hodgkin lymphoma, classical]

Primary cutaneous follicle center lymphoma (PCFCL ) is the most frequent cutaneous B-cell lymphoma . A 62 -year -old man presented with a solitary indolent subcutaneous nodule for 3 years duration , without other abnormalities . Histological examination showed lymphoproliferation with a nodular growth pattern characterized by fibrous collagen bands surrounding nodules . The nodules were composed of medium-sized centrocytes admixed with many large multilobulated and lacunar cells without eosinophils or granulomatous aspect . Hodgkin-like cells were CD 30 +, CD 15 +, PAX 5 +, OCT 2 +, BOB 1 +, MUM 1 +, Ki 67 +, Bcl 6 + and focally CD 2 0 + and EMA-, CD 7 9 a-, Bcl 2 - and CD 10 -. The medium-sized cells were CD 2 0 +, CD 7 9 a +, Bcl 2 +, Bcl 6 + and CD 10 +, enmeshed in a network of CD 2 1 -positive follicular dendritic cells . Epstein-Barr virus detection was negative . Interphase fluorescence in situ hybridization showed the absence of BCL 2 or BCL 6 rearrangement . In such a case , the presence of Hodgkin-like cells intermixed with the tumor population may result in a pitfall diagnosis of classical Hodgkin lymphoma (CHL ). Differential diagnoses to be ruled out are secondary or primary skin localization of rather CHL , or systemic follicular lymphoma . Several clinical , radiological , histological , immunohistochemical and molecular arguments indicated the diagnosis of PCFCL . To our knowledge , this is the first report of PCFCL with Hodgkin-like cells .