Fine-needle aspiration of intrapancreatic accessory spleen: cytomorphologic features and differential diagnosis.

TitleFine-needle aspiration of intrapancreatic accessory spleen: cytomorphologic features and differential diagnosis.
Publication TypeJournal Article
Year of Publication2012
AuthorsTatsas AD, Owens CL, Siddiqui MT, Hruban RH, Ali SZ
JournalCancer Cytopathol
Volume120
Issue4
Pagination261-8
Date Published2012 Aug 25
ISSN1934-6638
KeywordsAged, Biopsy, Fine-Needle, Diagnosis, Differential, Endoscopy, Endosonography, Female, Humans, Male, Middle Aged, Pancreatic Neoplasms, Prognosis, Splenic Diseases
Abstract

BACKGROUND: Intrapancreatic accessory spleen (IPAS) is a rare benign lesion of the pancreas that frequently clinically and radiographically mimics a solid neoplasm. Very rarely, epidermoid cysts may form in IPAS and be mistaken for a cystic neoplasm of the pancreas on radiographic imaging. IPAS and epidermoid cyst involving intrapancreatic cyst (ECIPAS) are benign, and, if recognized, do not require surgical intervention. There are few reports of the cytopathologic features of IPAS diagnosed by fine-needle aspiration (FNA).

METHODS: Here we report a series of 6 cases of endoscopic ultrasound (EUS)-guided FNA of IPAS, 3 of which had histological confirmation, including 1 case of histologically confirmed ECIPAS.

RESULTS: Cytomorphologic features of IPAS include a polymorphous population of hematopoietic cells, including lymphocytes, eosinophils, histiocytes, plasma cells, and red blood cells, admixed with numerous small blood vessels representing splenic sinusoids. CD8 immunostaining of cell block or core biopsy material highlights splenic endothelial cells and confirms the diagnosis. FNA of ECIPAS reveals predominantly macrophages and proteinaceous debris.

CONCLUSIONS: Diagnostic pitfalls include pancreatic neuroendocrine tumor. If IPAS is recognized as a diagnostic consideration on EUS-FNA, unnecessary surgical resection may be avoided.

DOI10.1002/cncy.21185
Alternate JournalCancer Cytopathol
PubMed ID22298506
Related Faculty: 
Momin Siddiqui, M.D.

Pathology & Laboratory Medicine 1300 York Avenue New York, NY 10065 Phone: (212) 746-6464
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