Kontrastverstärkte Endosonographie zur Verbesserung der Differenzialdiagnose zwischen chronischer Pankreatitis und Pankreaskarzinom

Abstract

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate contrast-enhanced endosonography as a method for improving the differentiation between chronic focal pancreatitis and ductal pancreatic cancer, based on perfusion characteristics of the microcirculation. PATIENTS AND METHOD: In 194 patients [75 women, 119 men; age: 64 ± 11 years] with chronic pancreatitis (n = 73) or pancreatic cancer (n = 121), pancreatic lesions were examined by conventional endoscopic B-mode ultrasound, power Doppler ultrasound and contrast-enhanced power mode, using the following criteria for malignant lesions: no detectable vascularization with conventional power Doppler scanning, irregular appearance of arterial vessels over a short distance using contrast-enhanced technique and no detection of venous vessels inside the lesion. A malignant lesion was assumed to be present if all criteria were detectable. The criteria of chronic pancreatitis without neoplasia were defined as no detectable vascularization before injection, regular appearance of vessels over a distance of at least 20 mm after injection of the contrast medium and detection of arterial and venous vessels. The gold standard was the histological diagnosis by endoscopic ultrasound (EUS)-guided fine needle aspiration cytology or operation. RESULTS: Using conventional EUS the diagnosis was correct in 96 of 121 patients with pancreatic cancer (sensitivity 79.3 ; 95 % confindence interval 71 - 85.2 %) and in 60 of 73 patients with chronic pancreatitis (specificity 82.2 [71.5 - 90.2 %]). Using contrast-enhanced EUS malignant pancreatic lesions were correctly diagnosed in 111 of 121 patients, thus increasing sensitivity to 91.7 (85.3 - 96 %). In 70 of 73 patients chronic inflammatory pancreatitis was correctly diagnosed (specificity 95.9 [88.5 - 99,1 %]). CONCLUSION: Contrast-enhanced endoscopic ultrasound improves the differentiation between chronic pancreatitis and pancreatic carcinoma.