Intrapancreatic accessory spleen: investigative dilemmas and role of EUS-guided FNA for diagnostic confirmation.

Context: We submit a case of intrapancreatic accessory spleen.

Case Report: A 33-year-old patient with history of dyspepsia underwent imaging studies suggestive of a neuroendocrine tumor. After referral to our institute, endoscopic ultrasound guided fine needle aspiration (EUS-FNA) confirmed diagnosis as intrapancreatic accessory spleen.

Discussion: An accessory spleen may develop from estranged mesenchymal cells due to fusion failure of the splenic anlage. The prevalence of an accessory spleen is 10-30% with 80% of them present at the splenic hilum and 17% in the pancreatic tail. Intrapancreatic accessory spleen is commonly misdiagnosed as a pancreatic tumor. Since, the differential diagnosis includes pancreatic neuroendocrine tumors, additional investigation with EUS-FNA should be considered when radiological diagnosis is not definitive.

Conclusion: For diagnosis of intrapancreatic accessory spleen, radiographic imaging is useful, but lacks specificity without tissue diagnosis. Diagnosis can be safely and reliably established with EUS-FNA, leading to a benign prognosis and avoidance of unnecessary surgical intervention.