Pancreatic Splenosis Mimicking Neuroendocrine Tumors:

Abstract

-Context -Pancreatic splenosis is a benign condition which can mimic a pancreatic neoplasm. Objective -To describe the role of the endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of pancreatic nodules suspicious for pancreatic splenosis. Method -From 1997 to 2011, patients with pancreatic solid tumors suspicious for splenosis by computed tomography and/or magnetic resonance imaging were referred to EUS-FNA. Those cases with pancreatic splenosis confirmed by EUS-FNA or surgery were included. Endosonographic findings and clinicopathologic features were also analysed. Results -A total of 2,060 patients with pancreatic solid tumors underwent EUS-FNA. Fourteen (0.6%) cases with pancreatic splenosis were found. After applying exclusion criteria, 11 patients were selected. Most patients were male (7), young (mean age: 42 years) and asymptomatic (8). Endoscopic ultrasound imaging alone suspected pancreatic splenosis in 6 cases, and neuroendocrine tumors in 5 cases. Pancreatic splenosis was found most commonly in the tail, was round, hypoechoic, with homogeneous pattern, regular borders, and with scintigraphy negative for somatostatin receptors. The average diameter of these nodules identified by endoscopic ultrasound was 2.15 cm. Microhistology obtained by EUS-FNA confirmed the diagnosis in 9/10 patients. Conclusion -Pancreatic splenosis can be diagnosed by EUS-FNA. Microhistology prevents unnecessary surgeries, and reassures asymptomatic patients with hypoechoic, homogeneous, and well circumscribed pancreatic nodules.

Intrapancreatic Accessory Spleen: A Diagnosis Not to Forget!

“…As a well-defined homogeneous and hypervascular lesion, it is most frequently misdiagnosed as a pancreatic NET. Octreotide scan has a high sensitivity (70–95%) for the detection of gastrointestinal NET and can be useful in the differential diagnosis from this pancreatic neoplasm [8, 9]. However, false-positive results have been reported in IPAS.…”

“…Other imaging modalities that have been proven to help identify IPAS include 99m Tc-sulfur colloid scintigraphy and contrast-enhanced EUS [2]. There are very few studies characterizing EUS features of IPAS, and the largest published case series included only 11 patients [9]. IPAS is endosonographically described as a round-to-oval-shaped, small lesion, usually less than 2 cm in diameter, with well-defined margins, a homogeneous echotexture, and an echogenicity lower than the adjacent pancreas and identical to that of the spleen.…”

“…Fortunately, this percentage is decreasing with the improved radiologic and endoscopic sampling diagnostic capabilities, in particular with EUS-FNA. EUS-FNA has been demonstrated to be a safe and effective tool to obtain a definitive IPAS diagnosis [1, 2, 7, 8, 9, 10, 11, 12, 13]. In the largest study of IPAS diagnosis established using EUS-FNA, this technique was successful in 90% of the cases, and no complications were reported [9].…”

“…EUS-FNA has been demonstrated to be a safe and effective tool to obtain a definitive IPAS diagnosis [1, 2, 7, 8, 9, 10, 11, 12, 13]. In the largest study of IPAS diagnosis established using EUS-FNA, this technique was successful in 90% of the cases, and no complications were reported [9]. The cytologic features of the splenic tissue are characterized by small lymphocytes with a mixed inflammatory infiltrate with the appearance of the white pulp and presence of thin-walled blood vessels, which represent the splenic sinuses.…”

An intrapancreatic accessory spleen presenting as a rapidly growing pancreatic mass after splenectomy in a patient with hereditary spherocytosis: a case report and literature review

“…Isolated splenosis has been rarely reported in the liver, kidney, mesoappendix and stomach [ 7 ]. Pancreatic splenosis occurs usually after splenic trauma and surgery [ 8 ].…”