Alexander Ramirez, MD, Wade G Douglas, MD, FACS. Tallahassee Memorial HealthCare, Florida State University College of Medicine
Introduction: Accessory spleen has been reported in about 30 % of autopsy studies (1) and until 65% of patients after splenectomy (2). The tail of the pancreas is the second most common location of accessory spleen (1). It is very important to identify the intrapancreatic accessory spleen without invasive diagnostic tests because there are few real indications for surgical resection (3). Intrapancreatic accessory spleen has rarely been noted radiologically before surgery and when there is concern about the differential diagnosis, especially with very high vascular tumors, surgical resection is indicated.
Case report: We presented a case of a 33 year-old male with a history of recent cholecystectomy that developed nausea and vomiting a few days after being discharged from the hospital. He was seen in the Emergency Room for these symptoms and a CT scan of the abdomen and pelvis revealed a 2.9 cm solid tumor in the tail of the pancreas (Figure 1, 2). The patient denied fatigue, diarrhea, hypoglycemic or syncopal episodes. All the endocrine markers were negative and the patient was scheduled for a robotic distal pancreatectomy and splenectomy.
The procedure was done robotically and during the procedure we used the laparoscopic ultrasound probe to identify the location of the pancreatic mass (Figure 3) and to confirm the total resection after the distal pancreatectomy was performed (Figure 4). The patient had an uneventful post operative period and was discharged home in the post operative day 2 in stable condition.  The pathology report shows a 2.5 x 2.x2 cm accessory spleen involving the parenchyma of the tail of the pancreas (Figure 5).
Conclusion: Intrapancreatic accessory spleens can radiographically mimic a malignant process. Surgery with pathology evaluation of the specimen is the only reliable means of diagnosis. This surgical procedure can be done laparoscopically or robotically  in a safe way. While intrapancreatic accessory spleen is a very rare condition, it is an important component of a complete differential diagnosis for a patient presenting with a pancreatic tail tumor.
References
1.Halpert B, Gyorkey F. Lesions observed in accessory spleens of 311 patients. Am J Clin Pathol.1959;32:165–168.
2.Eraklis AJ, Filler RM. Splenectomy in childhood: a review of 1413 cases. J Pediatr Surg.1972;7:382–388.
3. Kurmann A, Michel J, Stauffer E. Egger B. Intrapancreatic Accessory Spleen Misdiagnosed as a Nonsecreting Endocrine Tumor: Case Report and Review of the Literature. Case Rep Gastroenterol. 2010 May-Aug; 4(2): 210–214.
