Contrast-Enhanced Sonography of Small Pancreatic Mass Lesions

Objective. To evaluate the usefulness of contrast‐enhanced wideband harmonic gray scale sonography in assessing the vascularity of small pancreatic mass lesions. Methods. Twenty‐five patients with 25 pancreatic mass lesions (20 pancreatic carcinomas, 1 islet cell tumor, 1 malignant lymphoma, and 3 focal inflammatory pancreatic masses due to chronic pancreatitis) were examined. All patients held their breath for 20 to 50 seconds after injection of a contrast agent while the vascularity of the tumor was observed on contrast‐enhanced wideband harmonic gray scale sonography (early phase). We then monitored the tumor enhancement 60 to 120 seconds after the injection while the patients held their breath for a few seconds (delayed phase). Results. All 20 (100%) of the pancreatic carcinomas showed no contrast enhancement in the early phase. Fifteen (75%) of the 20 pancreatic carcinomas also showed no contrast enhancement in the delayed phase. The remaining 5 (25%) pancreatic carcinomas showed mild enhancement in the peripheral regions of the tumor in the delayed phase. The other pancreatic masses showed mild or pronounced enhancement throughout the entire lesions in both the early and delayed phases. Conclusions. Contrast‐enhanced wideband harmonic gray scale sonography is a useful tool for differentiating pancreatic carcinomas from focal inflammatory pancreatic masses or hypervascular pancreatic tumors.