Abstract B33: Classification of pancreatic cysts in a minority population through cytokine profiling of cyst fluid fine-needle aspirate

Abstract

Abstract Pancreatic cyst detection rate has increased due to the widespread use of cross-sectional imaging. Pancreatic cysts can be divided pathologically into pseudocysts, non-neoplastic cysts such as serous cystadenomas, and pancreatic cystic neoplasms. Malignant potential is seen in pancreatic cystic neoplasms, particularly mucinous cystic neoplasms and intraductal papillary mucinous neoplasms. Proper identification of mucinous cysts warrants either continual surveillance or evaluation for surgical resection to prevent potential development of pancreatic adenocarcinoma. Large urban medical centers, serving a predominantly minority population with an increased incidence of pancreatic cancer, require accurate and prompt diagnosis of malignant cysts. Currently, the standard cyst fluid analyses include CEA, amylase and cytology. In many cases these are of limited value and new biomarkers need to be defined to assist in accurate designation of cyst type. Previous studies have used proteomic analyses to improve cyst identification. One candidate set of protein markers are cytokines, which are involved in cell-mediated responses. A subset of cytokines has been implicated in the carcinogenic process. We hypothesized that the cytokine concentration in the pancreatic cyst fluid obtained via endoscopic ultrasound fine-needle aspiration will be differentially detected and could be used as an additional test to differentiate mucinous cystadenomas and cystadenocarcinomas from pseudocysts and serous cystoadenomas. The study protocol was designed to determine the pancreatic cyst fluid cytokine levels between mucinous and nonmucinous pancreatic cysts using a slide-based quantitative multiplex cytokine antibody array (Raybiotech, Norcross, GA). The cytokine array allowed for the quantitative detection of 20 cytokines with the parallel measurement of individual cytokine standard curves. Initial screening of 18 samples (8 mucinous, 10 nonmucinous) demonstrated differential detection of multiple cytokine targets, such as IL-1α and IL-5 that were statistically significant (P<0.05). Both cytokines have been linked to protective effects and immune surveillance in the setting of cancer. Additional sample screening will assess cytokines found to be borderline non-significant and validate the preliminary cytokine hits. These types of biomarkers are easily measured by ELISA in a clinical laboratory and would be useful in clinical practice as an adjunct for pre-surgical cyst classification. The establishment of differential cytokine measurements between mucinous and nonmucinous cysts would play a role in enhancing detection of premalignant and malignant cysts and improving current surveillance strategies. In addition, examination of the role of these cytokines in cyst development and progression could lead to new insight into the role of inflammation in the biology of cysts. Citation Format: Rajesh Ramachandran, Larry Siu, Vadim Kurbatov, Evan Grossman, Frank Gress, Laura Martello. Classification of pancreatic cysts in a minority population through cytokine profiling of cyst fluid fine-needle aspirate. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Innovations in Research and Treatment; May 18-21, 2014; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2015;75(13 Suppl):Abstract nr B33.