A case of solid-pseudopapillary neoplasm, focusing on contrast-enhanced endoscopic ultrasonography

We used contrast-enhanced endoscopic ultrasonography (CE-EUS) to diagnose a case of solid-pseudopapillary neoplasm (SPN) in an adult man. A 58-year-old man was referred to our hospital because of a pancreatic mass found by positron emission tomography (PET) using ¹⁸F-fluorodeoxyglucose (FDG) during a medical checkup in 2009. Trans-abdominal ultrasonography revealed a 24-mm hypoechoic mass at the pancreatic tail with calcification inside. Multiphasic computed tomography (CT) showed a solid mass with delayed enhancement. EUS revealed a hypoechoic mass without lateral shadowing, and neither a septum nor cystic component was detected. CE-EUS using Sonazoid® showed a hypovascular mass compared with the surrounding pancreatic parenchyma, and the inside of the mass was enhanced like an alveolus nest, suggesting pseudopapillary change. Diagnosis of a solid-pseudopapillary neoplasm and a concomitant small neuroendocrine tumor was made by distal pancreatectomy.