Pancreatoblastoma: Imaging findings in 10 patients and review of the literature

PURPOSE: To describe the features of pancreatoblastoma at magnetic resonanc e (MR) imaging, computed tomography (CT), and ultrasonography (US). MATERIALS AND METHODS: Imaging and surgical findings in 10 patients (age ra nge, 2-20 years; mean age, 6.8 years) with pathologically proved pancreatob lastoma were reviewed for tumor size, organ of origin, definition and quali ty of tumor margins, tumor heterogeneity, calcification, enhancement, ascit es, biliary and/or pancreatic ductal dilatation, local invasion, adenopathy , vascular invasion, vascular encasement metastases, and signal intensity o n MR images. Results from 10 CT, seven US, and three MR imaging examination s were reviewed. RESULTS: Five of the 10 tumors were pancreatic; four others appeared to be pancreatic or hepatic. Most had well-defined margins (nine of 10), were het erogeneous (nine of 10), and enhanced (10 of 10). Other findings included c alcification (two of 10), biliary and pancreatic ductal dilatation (one of 10), and ascites (three of 10). Hepatic (two patients) and pelvic (two pati ents) metastases were present. Adenopathy (two patients) and vascular invas ion (one patient) were not identified,radiologically, Tumors had low to int ermediate signal intensity on T1-weighted images and high signal intensity on T2-weighted images. CONCLUSION: Pancreatoblastoma is typically a heterogeneous tumor with well- defined margins that may appear to arise from the pancreas or liver. It may behave aggressively, with localized vascular or bowel invasion or with wid espread metastatic disease. Although it is rare, it should be considered in the differential diagnosis of an upper abdominal mass in a child.