Diagnostic value of contrast-enhanced transabdominal ultrasound and contrast-enhanced endoscopic ultrasound in pancreatic cystic tumors

Purpose: Pancreatic cystic tumors account for approximately 1 – 2% of pancreatic tumors. Contrast-enhanced ultrasound has now been used for the differential diagnosis of pancreatic cancer. This research aimed to investigate the diagnostic value of contrast-enhanced transabdominal ultrasound (CEUS) and contrast-enhanced endoscopic ultrasound (CE-EUS) in pancreatic cystic tumors.

Material and methods: We prospectively reviewed database of patients diagnosed with pancreatic cystic tumors between April 2015 and October 2015 in our institute. The inclusion criteria were as follows: patients who underwent conventional ultrasonography, CEUS, CE-EUS, CT/MRI, endoscopic ultrasound guided-fine needle aspiration and were pathologically diagnosed with pancreatic cystic tumor. One radiologist with more than 20 years' experience in contrast-enhanced ultrasound read all the patients' imaging and made diagnosis. We compared the diagnostic results from CEUS and CE-EUS with that of histopathology and made comparisons between the diagnostic efficacy of CEUS and CE-EUS.

Results: A total of 55 patients were enrolled in this study. Diagnosis included pancreatic cystadenoma (n = 36), pancreatic pseudocyst (n = 6), intraductal papillary mucinous neoplasm of pancreas (n = 5), solid-pseudopallary tumor of pancreas (n = 3), pancreatic cyst (n = 3), and pancreatic cystadenocarcinoma (n = 2). The diagnostic accuracy of CE-EUS was significantly higher than that of CEUS (78.2% vs. 85.5%, P = 0.004). For 36 cases with pancreatic cystadenoma, CEUS and CE-EUS showed comparable diagnostic accuracy of 80.6% and 88.9%

(P = 0.25).

Conclusion: CE-EUS is more effective in the diagnosis of pancreatic cystic tumor than CEUS.