Mo1434 Natural History of Pancreatic Intraductal Papillary Mucinous Neoplasms: Clinical Evaluation of Sendai Criteria in a Large Cohort of Patients

Background: Intraductal papillary mucinous neoplasms (IPMN) are mucin-produc ing, pancreatic cystic tumors, with a long-term potential for progression to adeno carcinoma. The Sendai criteria, based on imaging features, can differentiate the lesions into high and low risk of progression, influencing the patient management. However, few data are still available about clinical management and a better un derstanding in the natural history is critical. Aim: To evaluate the natural history of IPMN throughout clinical follow-up. Second end-point was to assess the clinical correlation between endoscopic ultrasound features and malignant histology. Material and Methods: All the patients with pancreatic IPMN, referred to our tertiary referral center between March 2003 and April 2013 were enrolled in the study. We divided patients into 3 groups, according to Sendai criteria: patients with cysts without signs of malignancy (1), patients with cysts with worrisome features (2) and patients with cysts with high risk stigmata (3). Univariate analysis and logistic regression were used to evaluate patients characteristics. Results: 371 patients were enrolled in the study period (171 M, mean age 67 years). 72/371 (19.4%) pts un derwent surgery after first EUS procedure, due to high risk stigmata. 199 pts were followed up for a period between 1 and 106 months since the diagnosis. During the FU period, 140/199 (70%) patients presented cysts without signs of malignancy. Any of these lesions showed malignant progression. The residual 59/199 pts showed worrisome features at EUS. Of these, 15/59 pts (25.4%) underwent surgery, for positive FNA cythology, during the follow up period, finding carcinoma in 7/15 pts (46.7%). Age, sex and worrisome features were not identified as predictive of ma lignancy progression at univariate logistic regression or multivariate analysis. Conclusions: Our results confirmed the Sendai criteria advice. Therefore, consid ering the management of IPMN with worrisome features is still controversial, and the high progression rate of patients with worrisome features we reported (11.8%), a short interval follow up is critical to avoid malignant progression.