ENDOSONOGRAPHY-GUIDED BIOPSY OF MEDIASTINAL AND PANCREATIC TUMORS

Background: Although endoscopic ultrasound (EUS) allows sensitive imag ing of the upper gastrointestinal (GI) tract, it remains difficult to differentiate between benign and malignant lesions on the basis of ult rasound morphology, The purpose of this study was to determine the val ue of EUS-guided biopsy for the diagnosis of submucosal and extralumin al tumors, Methods: EUS-guided biopsy was carried out in 50 patients w ith upper GI-tract lesions, All patients were examined using a flexibl e echoendoscope with a 5/7.5 MHz curved array transducer, A specially designed biopsy device (type Vilmann) with a fine needle (diameter 0.8 mm) was used for EUS-guided biopsy, Results: EUS-guided biopsy was pe rformed for evaluation of mediastinal lesions (n=15), pancreatic tumor s (n=26) and submucosal (n=5) or stenotic tumors of the esophagus (n=4 ), Fine-needle aspiration yielded diagnostic tissue samples in 44 of 5 0 patients (88%). Histology demonstrated benign lesions in 20 of 44 pa tients and malignant tumors in the other 24 patients. EUS-guided biops y failed in only six patients (12%): in four patients it was impossibl e to advance the needle into very hard pancreatic tumors; non-represen tative biopsy material was obtained in two further cases. The results of EUS-guided biopsy were validated by surgery (n=21), autopsy (n=3) o r clinical follow-up (n=20). After a mean follow-up of 16 months there is no evidence of malignancy in any of the patients with benign histo logy, The sensitivity and specificity of EUS-guided biopsy in the diag nosis of malignancy were 88% and 100%, respectively, None of the patie nts experienced complications related to endosonographic biopsy, Concl usions: EUS-guided biopsy with the Vilmann needle device is a safe and accurate method for tissue sampling of extraluminal lesions, This tec hnique considerably improves the diagnostic value of endosonography.