Pancreatic carcinoma versus chronic focal pancreatitis: contrast-enhanced power Doppler ultrasonography findings

We assessed the potential usefulness of contrast-enhanced power Doppler ultrasonography (US) for differentiating pancreatic carcinoma from chronic focal pancreatitis. Twenty-six consecutive patients with ductal carcinoma (n = 16) and chronic focal pancreatitis (n = 10) underwent power Doppler US examinations before and after intravenous injection of an air-based contrast agent (Levovist, Schering, Berlin, Germany). Final diagnosis was obtained by surgery in all patients. The following parameters before and after intravenous administration of contrast agent were evaluated for each lesion: number, morphology and course of the vessels within the lesion and time to maximum detectable enhancement. Number of the lesion vessels and time to maximum enhancement for each lesion were compared by with Student t test. After injection of contrast agent, nine of 16 (56.2%) carcinomas showed a larger total number of vessels (p < 0.005) and faster enhancement (p < 0.0001) compared with chronic focal pancreatitis. Irregular vessels with a serpiginous course that penetrated the tumor was predominant in carcinoma (eight of 16 cases), whereas focal pancreatitis presented mostly as avascular masses (five of 10 cases). Contrast-enhanced power Doppler US provides useful findings for differentiating pancreatic carcinoma from chronic focal pancreatitis.