[410] Increased Diagnostic Efficiency of Endoscopic Ultrasound (EUS)-Guided Fine Needle Aspiration (FNA) of Pancreatic Cysts (PC) Submitted in Sure Path
Liquid Based Medium Using Cell Block Preparation
M Rendi, LJ Dumont, FM Quinlisk, SR Gordon, V Padmanabhan. Dartmouth Hitchcock Medical Center, Lebanon
Background: Cysts in the pancreas are increasingly being identified due to increased use of high-resolution imaging. They often present a diagnostic challenge given that they may represent malignant or pre-malignant lesions. Cytology of EUS-guided FNA of PC lacks sensitivity but can have a high specificity for mucinous neoplasms and malignancies. However, the method by which cells are prepared and analyzed for cytology may significantly impact how often a diagnosis can be made from a sample.This study investigates the diagnostic efficiency (% of specimens adequate for diagnosis) and the diagnostic accuracy (defined as correlation to final clinical diagnosis) of PC aspirates evaluated by the SurePathTM liquid based preparation (LBP) (medium used in our laboratory) compared with concurrent cell block (CB) preparation.
Design: Sixty-two cases of FNA from PC with both a LBP and concurrent CB preparation were reviewed by two independent observers. The LBP was evaluated first with subsequent review of the CB with an independent diagnosis. The diagnostic accuracy of each method was then compared with the final clinical diagnosis and cyst-fluid amylase, CEA, and other tumor markers levels.
Results:
| Mucinous Neoplasm | 14 |
| Intraductal Papillary Mucinous Neoplasm | 14 |
| Serous Cystadenoma | 2 |
| Pseudocyst | 13 |
| Pancreatic Endocrine Neoplasm | 1 |
| Benign cyst NOS | 1 |
| Abscess | 2 |
| Non-diagnostic | 15 |
CB were significantly more often diagnostically useful (72.1% diagnostic) than the LBP (34.3% diagnostic) p<0.0001. Of 27 cases where only one preparation was diagnostic, the CB was diagnostic 92.5% of the time whereas the LBP was diagnostic 7.5% of the time. Diagnostic accuracy was extremely high (98%) using both the LBP and the CB. Both the LBP and the CB diagnoses correlated well with cystic CEA levels and the final clinical diagnosis.
Conclusions: Diagnostic efficiency of the CB was far superior to that of the LBP. These results suggest that although the diagnostic accuracy of the LBP and CB are comparable, the diagnostic efficiency of the cell block preparation is significantly better than that of the SurePathTM liquid-based preparation. As submission of a cell block preparation is not currently standard of care, these results have important implications for laboratory practice and suggest that a cell block should always be submitted for evaluation of EUS-guided fine needle aspiration of pancreatic cysts.
Category: Cytopathology
Wednesday, March 11, 2009 1:00 PM
Poster Session VI # 58, Wednesday Afternoon