Accuracy, sensitivity and specificity of fine needle aspiration biopsy in salivary gland tumours: A retrospective study

Abstract

The aim of this study was to evaluate the diagnostic accuracy, sensitivity and specificity of fine needle aspiration biopsies (FNAB) of salivary gland tumours performed at the Erasto Gaertner Hospital over the course of a four year period. A retrospective study was carried out between 2001-2005 to review the cases of patients with salivary gland tumours who had undergone pre-operative FNAB and had been diagnosed during post-operative histopathology examination. A total of 106 cases of salivary gland tumours were considered for this study, but 27 cases (25.5%) of the samples were considered unsatisfactory for analysis. The sensitivity, specificity and accuracy were calculated considering only the 79 benign and malignant cases in which FNAB provided sufficient samples for analysis. Based on these data, the value of sensitivity was 68.2% (15/22), specificity was 87.7% (50/57), accuracy was 82.3% (65/79), positive predictive value was 68.2% (15/22) and negative predictive value was 87.7% (50/57). Despite the high rate of inadequate samples obtained in the FNAB in this study, the technique offers high specificity, accuracy and acceptable sensitivity.