Neutrophilic phagocytosis by tumor cells. A feature to consider in the differential diagnosis in fine needle aspiration smears.

Objective: To analyze neutrophilic phagocytosis by tumor cells in fine needle aspirate (FNA) smears from different types of tumor.
Study Design: A retrospective review of a total of 7 cases showing prominent neutrophilic phagocytosis by tumor cells in FNA smears during the period July 2003-December 2004.
Results: This feature was seen in malignant fibrous histiocytoma and poorly differentiated renal cell carcinoma in addition to giant cell carcinoma of the lung.
Conclusion: Neutrophilic phagocytosis by tumor cells is seen in FNA smears and on cytomorphology. The differential diagnoses should include both pleomorphic sarcomas and carcinomas.