Fine-needle aspiration cytology of adrenal masses in noncancer patients - Clinicoradiologic and histologic correlations in functioning and nonfunctioning tumors

BACKGROUND. Image-guided, fine-needle aspiration (FNA) cytology is performed currently in patients with malignant disease who have suspected adrenal metastases. The objective of this study was to evaluate the usefulness and safety of FNA cytology in patients with incidental adrenal masses and functioning tumors. METHODS. Computed tomography (CT)-guided or ultrasound-guided aspirates using 21-23-gauge needles were performed successfully in 70 patients with functioning (n = 38 patients) and nonfunctioning (n = 32 patients) adrenal masses (median size, 4 cm; range, 3-12 cm) that were detected previously by CT scans. RESULTS. Definitive histology was available in 68 patients (97.1%), showing 53 benign tumors (77.9%), 11 primitive malignant tumors (16.2%), and 4 unsuspected adrenal metastases (5.9%) in patients with unknown primary tumors. In two patients with aspirate reports that ruled out malignancy, the mass was unchanged on CT scan follow-up; thus, they were considered benign lesions. The benign masses were significantly smaller (P < 0.01), although seven malignant tumors (46.7%) measured 3-4 cm in greatest dimension, and eight benign lesions (14.5%) measured 5-6 cm in greatest dimension. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 66.7%, 96.4%, 83.3%, 91.4%, and 90.0%, respectively, for CT scan and 93.3%, 100%, 100%, 98.2%, and 98.6%, respectively, for FNA cytology. The morbidity rate of image-guided FNA cytology was 4.3% (two patients with self-limited, asymptomatic pneumothorax and one patient with spontaneously resolved adrenal hematoma). CONCLUSIONS. Adrenal FNA cytology represents a safe and specific procedure for evaluating patients with adrenal masses measuring > 2 cm in greatest dimension. FNA is able to reveal malignancies and unsuspected pheochromocytomas and should be performed in all patients with adrenal tumors whenever requested for surgical planning. (C) 2001 American Cancer Society.