Analysis of the diagnostic yield of endoscopic ultrasonography-guided fine-needle aspiration in patients with a suspected pancreatic malignancy

ABSTRACT Objectives: to determine the diagnostic yield of endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) for suspected pancreatic malignancy. As well as to identify factors that affect the incidence of false-negative cases and evaluate the value of repeated EUS-FNA in patients with inconclusive results. Methods: we retrospectively evaluated the data of patients who underwent EUS-FNA due to a suspected pancreatic malignancy in our hospital from January 2015 to December 2016. Results: a total of 194 EUS-FNA procedures performed and 175 cases were analyzed. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were 83.4% (151/181), 100% (13/13), 100% (151/151), 30.2% (13/43), and 84.5% (164/194), respectively. The combination of cytological and histological examination significantly increased the diagnostic performance compared to either method alone. The diagnostic sensitivity in metastatic tumors was significantly lower than that for adenocarcinoma. EUS-FNA performed using standard needles combined with the "slow-pull" technique had a lower sensitivity than other methods. According to the multivariate analysis, neither the combination of needle type and suction technique nor final diagnosis were independent factors that affected the diagnostic sensitivity. The sensitivity of repeated EUS-FNA was 50.0% (8/16). Definitive results after a repeated puncture were more likely for pancreatic body and tail masses, heterogeneous lesions and poorly demarcated lesions. However, the difference was not significant. Conclusions: EUS-FNA was accurate for the evaluation of a suspected pancreatic malignancy. Metastatic tumors and the use of a standard needle in combination with the slow-pull technique may increase the incidence of false-negative results. Repeated EUS-FNA has limited value but should be considered for selected cases where the suspicion of malignancy persists.