Case Report of Recurrent Metastatic Pancreatic Neuroendocrine Tumor with Gastric Invasion: Consequences of Potential Needle-Tract Seeding from Fine-Needle Aspiration.

Background: Pancreatic neuroendocrine tumors (PNETs) are relatively rare, and data guiding management of metastatic lesions are scarce. Hepatic metastases are most common; here we describe a case of metastatic PNET implanted into the posterior gastric cardia. Case Presentation: This case study describes the progression of a 44-year-old man with a history of pancreatic neuroendocrine tumor (PNET) resected through distal pancreatectomy and splenectomy who developed recurrent disease in his stomach with extension into the left adrenal fossa 17 months after initial resection. He subsequently underwent a total gastrectomy and left adrenalectomy with en bloc resection of this recurrence without complication. Final pathology revealed a morphologically similar PNET with positivity for CAM5.2, chromogranin A, and synaptophysin. Conclusion: The unusual location of his recurrence could suggest that his preoperative endoscopic ultrasound and fine-needle aspiration may have had a role in seeding the posterior gastric wall, highlighting the risk of performing this diagnostic procedure in the setting of suspected pancreatic malignancy.