Mo1439 Management Strategy of Pancreatic Cyst Patients Based on Integrated Molecular Pathology in 492 Patients: the Final Results of a Multicenter Study

Abstract

retrospective chart review was performed on consecutive patients who underwent EUS with FNA of pancreatic cysts at one tertiary referral center from 2000-08 and second referral center from 2009 2012. Patients with personal or family history of pancreatic adenocarcinoma, known acute or chronic pancreatitis, cysts!15mm, or imaging features suspicious for malignancy on EUS (cysts with solid component, mural nodules, thick cyst wall and dilated pancreatic duct) were excluded. All patients who had either carcinoembryonic antigen (CEA) or cytological examination of the cystic fluid performed were included in the study. The cytology was considered diagnostic if it showed malignancy (defined as malignant cells, atypical cells or cells suspicious/suggestive of malignancy) or definitive diagnosis of serous or mucinous cyst. The cytology was negative if the sample was not satisfactory, acellular, paucicellular or had benign epithelial cells. Malignancy was confirmed by surgical pathology or metastases on imaging. CEA O192 ng/ml was considered mucinous,! 5ng/ml serous and values in between indeterminate. Results: 125 patients with benign appearing pancreatic cysts were included in the study. Cyst sizes were: 42 patients (33.6%) with cyst size 15-19mm; 45 patients (36%) 20-29mm and 37 patients (29.6%) O19mm. Cyst size wasn’t available in 1 patient. Samples were sent for cytology in 111 (89%) of these patients: 3 (2.7%) patients had malignant cells, 2 (1.8%) were diagnostic of mucinous cyst and 106 (95.4%) were indeterminate. 2/3 patients with malignant cytology underwent surgery and the pathology was completely benign. The third patient did not undergo surgery. Follow-up imaging after 4 years showed stable size of cyst and no evidence of malignancy. 1/2 patients where cytology was diagnostic of mucinous cyst, CEA was O192 ng/ml, it was not sent in the other due to viscous and insufficient fluid. In cysts when CEA was measured, the diagnostic yield of CEA was 68%. Cytology did not add have incremental diagnostic value over CEA and added $150 250 to the total cost of the procedure. Conclusion: Cytological analysis of benign appearing cysts is unnecessary and adds cost to the procedure without any incremental benefit. It can also lead to unnecessary surgeries. Checking CEA only may be sufficient and the most costeffective approach.