Cyst wall puncture and aspiration during EUS-guided fine needle aspiration may increase the diagnostic yield of mucinous cysts of the pancreas.

BACKGROUND

Pancreatic cysts are common, however, their diagnosis and classification remains a challenge despite advances in cross-sectional imaging and endoscopic ultrasound with fine needle aspiration (EUS-FNA).

OBJECTIVE

To determine the incremental yield of cytologic examination of material obtained from targeted fine needle aspiration ("puncture") of the cyst wall after aspiration of fluid for CEA.

DESIGN

Retrospective consecutive series.

PATIENTS AND

SETTING

Consecutive patients undergoing EUS-FNA of a pancreatic cyst by 2 expert endoscopists at a single tertiary care center between January 2006 and June 2008.

INTERVENTION: Standard EUS-FNA of pancreatic cysts was carried out, and after cyst fluid aspiration the cyst wall was punctured and aspirated (CWP) to obtain epithelium for cytologic analysis.

MAIN OUTCOME MEASUREMENTS: The diagnostic yields of carcinoembryonic antigen (CEA) obtained from cyst fluid and of cytology obtained from CWP. CEA greater than192 ng/mL was considered diagnostic of a mucinous cyst.

RESULTS

One hundred seven patients underwent EUS-FNA with CWP. Sixteen (31%) of 52 patients with CEA <192 ng/mL had cytology positive for mucinous epithelium, whereas 15 (47%) of 32 cysts with an insufficient amount of fluid for CEA analysis had positive cytology from CWP. The additional, cumulative diagnostic yield for mucinous cysts was therefore, 37%. Of 55 cysts diagnosed as mucinous, more (56%) were diagnosed by CWP cytology alone than by CEA (P<0.05).

LIMITATIONS: Retrospective design and limited surgical pathology.

CONCLUSIONS

Cyst wall puncture and aspiration during routine EUS-FNA may be a safe, easily applied, and inexpensive technique for improving the diagnostic yield for mucinous cysts of the pancreas.