Endoscopic ultrasound-guided fine-needle aspiration cytology in the diagnosis of intraductal papillary mucinous neoplasms of the pancreas. A study of 8 cases.
BACKGROUND
Intraductal papillary mucinous neoplasm (IPMN) is an increasingly recognized neoplasm of the pancreas, accounting for 5% of pancreatic neoplasms, it is considered difficult to diagnose by fine-needle aspiration (FNA) cytology.


OBJECTIVE
The aim of this study was to investigate the role of EUS-guided FNA cytology in the diagnosis of IPMN of the pancreas.


METHODS
Eight cases of surgically proven IPMN with pre-operative endoscopic ultrasound-guided (EUS-guided) FNA cytology were collected for retrospective analysis.


METHODS
EUS-FNA cytology was performed with the on-site attendance of a cytopathologist in all cases. EUS/clinical findings, macroscopic/microscopic features of cell blocks and smears, and immunocytochemical stains accompanied by histopathologic diagnosis were recorded and studied.


RESULTS
EUS revealed hypoechoic masses in the head of pancreas (n=6) and in the body/tail (n=2), measuring from 16.6 to 35.8 mm. In all cases, the hypoechoic mass had a distinctive distribution, involving the main pancreatic duct and/or the associated large branch ducts while intraductal nodules or multiple cysts were detected. Cytological specimens were characterized by a background containing abundant mucin in all cases and rarely by inflammation (neutrophils and histiocytes) (n=4). Neoplastic cells were entrapped in a mucinous background either single or loosely cohesive, and forming papillae in 7 cases. Mucinous epithelium was observed in all cases. Single atypical and irregular clusters were found in 3 cases (which were cytologically described as highly suggestive malignant IPMNs, and were histologically confirmed). Two cases were diagnosed as benign IPMN and, in 3 cases, the biological behavior was not easy to determine by cytology alone (histologically diagnosed as borderline). The histological diagnosis confirmed the FNA cytology diagnosis: 3 malignant IPMNs, 2 benign IPMNs and 3 borderline IPMNs. Immunostains were available in 5 out of 8 cases. Mucin 1 (MUC-1) was positive in 2 cases of malignant IPMN (histologically classified as null type ad intestinal type), mucin 2 (MUC-2) was positive in 3 cases (2 malignant both of the intestinal type, and 1 benign of the intestinal type I) and c-erbB2 was positive in 3 cases (2 benign - null and intestinal type - and 1 malignant null type).


CONCLUSIONS
The characteristic pre-operative EUS findings and cytomorphologic features, in addition to the immunocytochemical profile, were accurate indications and coincided with the final/post-operative histological diagnosis of IPMN.
Salla
Charitini
C
Department of Cytology, Athens General Hospital, Athens, Greece.
Chatzipantelis
Paschalis
P
Konstantinou
Panagiotis
P
Karoumpalis
Ioannis
I
Sakellariou
Stratigoula
S
Pantazopoulou
Akrivi
A
Manika
Zisoula
Z
D002288:Adenocarcinoma, Mucinous / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology*; D000231:Adenocarcinoma, Papillary / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology*; D000368:Aged; D044963:Biopsy, Fine-Needle / Q000379:methods; D019160:Endosonography / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009077:Mucins / Q000378:metabolism; D010190:Pancreatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D012189:Retrospective Studies
D009077:Mucins; D018719:Erb-b2 Receptor Tyrosine Kinases