I see a nodular/follicular B-cell rich lymphoprolifertaion with some giant cells, polykaryocytes (Warthin-Finkledey)and hemophagocytosis. To obtain a specific diagnosis we need more:  
1. HIV status?  
2. Previous viral infections?  
3. EBV serology?  
4. Familial history?  
5. Peripheral blood counts? CD4/CD8 ratio in the blood? Signs of hemophagocytosis?  
6. Phenotype of the giant cells (CD20? PAX5? EMA?)  
7. Phenotype of the cells surrounding the giant cells (PD1? CD57?)  
8. Distribution of the mantle zones (IgD) and of the FDC (CD23?)  

Because of the presence of Warthin-Finkledey giant cells I consider a measles lymphadenitis.

Dear Munaf Desai, would you be so kind to update us on the clinical course and your further diagnostic steps in that case?

Thanks Dr Alexander Tzankov and Dr Bart Vrugt for your comment and sorry for late response. (I saw your second comment today only, may be the email notification not received or missed by me?  
 
The patient is HIV negative, no history of previous viral infection and no significant family history.  
 
The patient is/was asymptomatic and CBC were normal, no hemophagocytosis suspected on blood film. The initial clinical impression was of lipoma only. As all required markers are not available, the patient has been referred to oncohematology center for further work up.