Diagnostic Challenges of Pancreatic Cysts: A Proposal for a Multimodality Approach
Irma V Oliva, Christina Ky, Nikki Salami, Neda A Moatamed, Sophia K Apple. UCLA, David Geffen School of Medicine, Los Angeles, CA
Background: The diagnostic distinction between mucinous and non-mucinous cystic lesions of the pancreas is clinically important as it has significant treatment implications. Mucinous cystic lesions include mucinous cystic neoplasm (MCN) and intraductal papillary mucinous neoplasm (IPMN), and require surgical excision. Non-mucinous lesions include serous cystic neoplasms and cystic neuroendocrine tumors and are managed with observation/follow-up. While EUS-FNA has emerged as the primary modality for obtaining an FNA sample from pancreatic lesions, cystic lesions present unique challenges, including undersampling and the treacherous gastrointestinal contamination. We investigated a combination of parameters: endoscopic impression, cytologic evaluation, mucin staining, and cyst fluid chemical analysis.The purpose of this study was to assess the utility of a multimodality approach in discriminating non-mucinous from mucinous lesions.
Design: All EUS-FNA pancreatic cysts cases performed at our institution from January 2009 to December 2010 were retrieved. Cases with mural nodules/solid masses were excluded and only cases with available surgical follow-up information were selected. The endoscopic findings, cytologic features, mucicarmine stains, and cyst fluid chemistry results were reviewed. The sensitivity and specificity of cytologic diagnosis were calculated using surgical follow-up as the gold standard.
Results: A total of 349 EUS-guided FNA procedures for pancreatic cystic lesions were performed. Of these, 65 fulfilled our criteria. Mean and median patient age were 62.0 and 67.0 years, respectively (range 31-84 years), 24 males and 41 females. Sensitivity, specificity, positive predictive and negative predictive values and accuracy were calculated for each parameter and combined parameters.