Role of endoscopic ultrasound-guided fine-needle aspiration in the diagnosis of space occupying lesions of the pancreas

Abstract

Introduction: Space occupying lesions (SOLs) of the pancreas are commonly encountered in day to day practice either as an incidental finding or during evaluation of symptomatic patients. The aim of the present study was to compare the final diagnosis at follow-up with diagnosis made at computed tomography (CT)/magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS). Materials and Methods: Retrospective analysis of EUS data of 131 patients referred for tissue diagnosis of SOL in pancreas was done. The lesions were classified as malignant, benign, and nonneoplastic by both CT/MRI and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in conjunction with clinical presentation, biochemical parameters, and tumor markers. Follow-up cases with a final diagnosis alone were included for the comparative analysis. Statistical Analysis: Chi-square test, sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) for CT/MRI and EUS-FNA were computed against the follow-up data. Results: Of the 131, there were 78 males (59.5%). The median age of presentation was 48 years (range: 11–82 years. Follow-up information on the final diagnosis was available for 54 patients. Confirmed diagnosis at follow-up was malignant lesion in 18, benign in 13 and 23 with a nonneoplastic lesion. When EUS-FNA outcome was compared with the definitive diagnosis of the 54 patients, it had a higher sensitivity for malignant (66.7% vs. 61.1%) and nonneoplastic lesions (78.3% vs. 73.9%) and was similar to CT/MRI for benign lesions (76.9% for both). EUS-FNA had a higher specificity (87.8% vs. 80.5%) with a good PPV for benign lesions (66.7% vs. 55.6%). CT/MRI was less accurate than EUS-FNA in predicting benign (79.6% vs. 85.2%) and nonneoplastic lesions (79.6% vs. 81.5%) compared to malignant lesions wherein it was similar at 81.5%. The high NPV with a lower PPV for both EUS/FNA and CT/MRI suggests that follow-up definitive diagnosis was superior to both –. Conclusions: Endoscopic ultrasound-guided fine-needle aspiration had a higher specificity, but low sensitivity for the both neoplastic and nonneoplastic lesion of the pancreas compared to the world literature. The overall EUS-FNA yield was low when compared to the follow-up definitive diagnosis.

Keywords

• endoscopic ultrasound
• fine-needle aspiration
• pancreatic lesion