Endoscopic ultrasound-guided fine needle aspiration of solid pseudopapillary tumors of the pancreas: a report of three cases
A 40-year-old female was diagnosed with a mass in the pancreatic body that was detected incidentally by abdominal ultrasonography during a general examination. All laboratory values were within normal levels: WBC, 5.32 × 103/µL; hemoglobin, 13.7 g/dL; platelets, 228 × 103/µL; AST/ALT, 16/9 U/L; amylase/lipase, 78.3/38.4 U/L; and CA 19-9, 28.6 U/mL. Abdominal CT showed no definite pancreatic lesion. MRI revealed a 1-cm sized, delayed enhancing lesion in the body of the pancreas. The tumor was a morphologically well-defined, hypoechoic mass by EUS imaging.\nEUS-FNA was performed five times using a 25-gauge needle via a transgastric approach without complications. Specimens were prepared for cytologic smears and cell blocks using the same method as described above. The initial impression based on the imaging studies was pancreatic SPT or pancreatic neuroendocrine tumor.\nCytologic smears and cell blocks showed hypercellular sheets or nests of atypical ductal epithelial cells with papillary features and a vascular core and some discohesive cell nests. Based on the characteristic histology, no immunostaining was performed. We interpreted the mass as a SPT.\nThe patient underwent laparoscopic pancreatic mass excision. We conducted immunohistochemical staining on the surgical specimen. Immunostaining was positive for vimentin, CD10, and β-catenin (), with focal positivity for synaptophysin (), and were negative for CD99, Ki-67, and CK19.