Fine-needle aspiration cytology of adrenal masses: a re-assessment with histological confirmation.

Abstract

Fine-needle aspiration (FNA) of adrenal masses is a method currently indicated in lesions suspected of being extra-adrenal in origin; even though its diagnostic reliability has already been determined in many studies, few have used histological examination obtained after adrenalectomy for diagnostic confirmation. To analyze the diagnostic performance of adrenal FNA in subjects with an available histological confirmation. Fifty subjects (26 benign adrenal lesions, 9 primary malignant lesions, and 15 metastatic lesions) who had undergone ultrasound (US)-guided adrenal FNA and then adrenalectomy were re-analyzed retrospectively. FNA guaranteed a sensitivity of 85.7% and a specificity of 100% in all subjects; after having divided the subjects into oncologic and non-oncologic groups, the sensitivity of the test in oncologic patients (100%) increased significantly compared to non-oncologic (57.1%) with no difference in specificity (100% in both groups). Considering also non-diagnostic samples in our analysis (no.=11; 22% of all samples studied), FNA correctly diagnosed malignancy only in 75% of the cases and benignancy only in 66.6%; however, even after including non-diagnostic samples, the percentage of correct malignancy diagnosis remained significantly higher in oncologic (93.3%) than in non-oncologic patients (44.4%) without significant statistical difference between the 2 groups regarding the percentage of correct benignancy diagnosis (respectively 100% and 63.6%). Our study, based on histological confirmation, underlines the low discriminant value of US-guided adrenal FNA, though the method may have value in oncologic patients.