Primary effusion lymphoma

It is a large B-cell lymphoma which presents as a pleural, pericardial or peritoneal effusion. There is no associated mass lesion or lymphadenopaty. Most cases arise in the setting of HIV infection. The prognosis is poor.

Cytologic diagnostic features

• Dispersed large cells
• Round or irregular nuclei, prominent nucleoli
• Abundant basophilic cytoplasm (Romanowsky stain)

Flow Cytometry on a fresh sample confirms the morphological findings