Cytologic findings in carotid body tumors

OBJECTIVE: To describe the cytologic findings in 13 cases of carotid body tumors (CBTs) and discuss the differential diagnoses. STUDY DESIGN: Cytologic smears were obtained from 13 cases of carotid body tumors by fine needle aspiration. All tumors were clinically suspected and later confirmed by arteriography or color Doppler ultrasonography. The cytomorphologic findings are described. RESULTS: The smears revealed hypercellularity, a bloody background, isolated and clusters of round to oval cells with indistinct cytoplasm, reticular chromatin, no prominent nucleoli, giant bare nuclei, anisocytosis, acinar structures and plasmacytoid cells. These findings suggested metastatic tumors. CONCLUSION: The cytologic diagnosis of CBTs is very difficult. The aspiration findings can be easily mistaken for those of metastatic tumors. However, when used with clinical and color Doppler findings, fine needle aspiration plays an important role in the preoperative diagnosis and management of CBTs.