Non-Hodgkin's lymphoma with extensive emperipolesis mimicking Rosai-Dorfman disease: A rare case report.

Emperipolesis is the hallmark finding for Rosai-Dorfman disease. Till now many studies in literatures have shown emperipolesis as a finding in other benign as well as malignant conditions. Very few cases of malignant lymphoma have this phenomenon. Herewith, we put forward a rare case of lymphoma with clinical presentation showing involvement of spleen, liver, lymph nodes as well as lleo-cecal region. Light microscopy revealed large to medium sized lymphoid cells with intervening plenty of histiocytes showing evidence of emperipolesis that mimics Rosai Dorfmann disease. Due to atypical clinical presentations we thought of lymphoma as a differential diagnosis. Further immunohistochemistry was performed using histiocytic as well as lymphoid markers. To our surprise, it turns out to be Non Hodgkin Lymphoma with extensive emperipolesis which is extremely rare in thorough literature search. This case is presented due to its unique clinical as well as histological presentations.