Reed-Sternberg-like cells in lymph node aspirates in the absence of Hodgkin's disease: pathologic significance and differential diagnosis.

We discuss nine cases identified at our institution with prominent Reed-Sternberg-like cells in fine-needle aspiration of lymph nodes in patients without Hodgkin's disease. Cytomorphology was studied using Diff-Quik and Papanicolaou-stained smears and flow cytometric analysis was performed in all cases. Clinical and/or histopathologic follow-up was reviewed. Of the nine cases, all were diagnosed as "atypical lymphoid proliferation" despite a negative flow cytometric analysis. Clinicopathologic follow-up revealed that three cases evolved into malignant non-Hodgkin's lymphoma and one case into a posttransplant lymphoproliferative disorder. The remaining five cases were benign in the follow-up period also, of which one case was later diagnosed as an inflammatory pseudotumor. In two cases of reactive hyperplasia and in the inflammatory pseudotumor case, an in situ hybridization stain for Epstein Barr virus (EBV) was positive. The significance and differential diagnosis of Reed-Sternberg-like cells in lymph nodes in the absence of Hodgkin's disease is discussed. Copyright 2002 Wiley-Liss, Inc.