The importance of endoscopic ultrasound fine-needle aspiration in the diagnosis of solid pseudopapillary tumor of the pancreas: two case reports

BACKGROUND: Solid pseudopapillary tumor of the pancreas, otherwise known as solid and cystic tumor or Frantz tumor, is an unusual form of pancreatic carcinoma, with unknown etiopathogenesis, that accounts for 0.2 to 2.7% of all pancreatic tumors. It is defined as an exocrine pancreatic neoplasia that mainly affects women between the second and third decade of life, and its management is not well defined. Endoscopic ultrasound offers a key anatomical advantage in accessing the pancreas and endoscopic ultrasound fine-needle aspiration has become the gold standard method for the diagnosis of pancreatic lesions. CASE PRESENTATION: Case 1: A 31-year-old white Hispanic woman presented with epigastric pain for 5 months. An abdominal ultrasound revealed a single 2 cm nodule in the uncinate process of her pancreas. Endoscopic ultrasound showed a regular, well-defined solid lesion with alternating cystic areas at the uncinate process of her pancreas, measuring 1.7 × 1.4 cm; endoscopic ultrasound fine-needle aspiration was then performed with cytopathological analysis compatible with solid pseudopapillary tumor. Body computed tomography confirmed the absence of metastases and she underwent conventional duodenopancreatectomy. However, she died 4 days after surgery due to postoperative surgical complications. Case 2: A 35-year-old Hispanic woman presented with left upper quadrant abdominal pain for 3 months, associated with a palpable mass at this region. A computed tomography scan showed a solitary nodule in the pancreatic body. Endoscopic ultrasound showed a regular, well-defined, homogeneous lesion with small anechoic (cystic) areas, measuring 2 × 2 cm, in between the pancreatic body and neck. Endoscopic ultrasound fine-needle aspiration was performed and cytopathological analysis was suggestive of a pseudopapillary solid tumor. She underwent a body-tail laparoscopic pancreatectomy with splenectomy. Nine months after the diagnosis, she remains asymptomatic, continuing regular follow-up in the oncology out-patient clinic. CONCLUSIONS: Solid pseudopapillary tumor is a rare pancreatic malignancy. Endoscopic ultrasound fine-needle aspiration is the gold standard method to characterize and diagnose this type of pancreatic lesion, making this an invaluable tool to help guide clinical management and improve the preoperative diagnostic yield.