ABSTRACT
BACKGROUND AND STUDY AIM: One of the problems in diagnosing pancreatic ductal adenocarcinoma (PDAC) is differentiation between PDAC cells and benign pancreatic tissue cells in cytologic samples. This study aimed to evaluate the usefulness of Maspin, CK17 and Ki-67 immunocytochemistry (ICC) in differentiation between these two groups of cells. MATERIALS AND METHODS: This retrospective study was carried on 80 cases of PDAC and 25 cell blocks of benign pancreatic tissue cells as a control group for evaluation of Maspin, CK17 and Ki-67 ICC. PDAC cases were sampled by endoscopic ultrasound guided fine needle aspiration cytology (EUS-FNAC), while cell blocks of control group were aspirated from benign pancreatic tissues that were obtained from the pancreatic surgically resected specimens. Immunostaining patterns, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of each antibody as well as possible antibody combined panels of these markers in differentiation between the two groups were evaluated. RESULTS: Positive immunoreactivity for Maspin, CK17 and Ki-67 were 92.5%, 80% and 72.5% in PDAC cases, respectively. In contrast to PDAC cases, all the cell blocks of benign pancreatic tissue cells were negative for these markers. Regarding different panels, combined use of Maspin, CK17 and Ki-67 together as a triple test (at least one of them is positive) achieved the highest sensitivity of 98.8%, specificity of 100%, PPV of 100%, NPV of 96.2% and accuracy of 99% in the differentiation between PDAC and benign pancreatic tissue. CONCLUSION: Employing this short panel [Maspin, CK17 and Ki-67] is helpful for better differentiation between PDAC and benign pancreatic tissue.