Binucleate cells in cytosmears: What do they signify?

Background: Although the classic Reed-Sternberg (RS) cell is considered a diagnostic of Hodgkin's disease, RS-like cells have been noted in various benign and malignant conditions. The presence of these cells can be a diagnostic challenge. Aims: Our aim was to see if cells morphologically resembling or identical to RS cells occur in conditions other than Hodgkin lymphoma (HL) and what proportion of cases show binucleate cells in various benign and malignant conditions. We also want to discuss the diagnostic utility of cytomorphological features in predicting HL. Material and Methods: This study is a retrospective analysis of 2086 cytology cases. The cytosmears were screened for the presence of binucleate cells. A detailed cytomorphological analysis of cytosmears with binucleate cells was performed, and the diagnostic utility of cytomorphological criteria in delineating HL was examined. Results: Out of 2086 smears, 55 (2.6%) cytosmears showed binucleated RS/RS-like cells. Out of these 55 cases, 6 were HL, 3 cases were non-HL (NHL), 3 were sarcoma, 32 were carcinoma, and 11 were benign/inflammatory lesions. The presence of prominent eosinophilic nucleoli, granulomas, and eosinophils had good sensitivity and specificity in predicting the diagnosis of HL. Conclusion: A detailed cytomorphological analysis is of limited value in categorizing the RS and RS-like cells. However, few cytomorphological features such as prominent eosinophilic nucleoli, eosinophils, granulomas, and lack of clustering of atypical cells can help us in predicting HL.