PROGRESSION OF CYSTIC PANCREATIC NEOPLASMS - A UNI-CENTER COHORT STUDY OVER 6 YEARS

Aims The purpose of this study was to evaluate the malignant potential of pancreatic cystic lesions and the precision of endosonographic diagnoses including the early detection of cysts with malignant potential.

Methods All patients referred between January 2012 and December 2018 to our tertiary referral center for EUS of pancreatic cystic lesions were included in this retrospective analysis. EUS was performed by 3 experienced gastroenterologists with Hitachi Preirus and Pentax echoendoscopes.

Results 456 patients with pancreatic cystic lesions were included in a database. 224 patients had cystic pancreatic neoplasms, the median age was 69.5 years. EUS diagnosis was 139 BD-IPMN, 16 MD-IPMN, 46 serous cystic neoplasia and 6 mucinous cystic neoplasia. Progression of size was rare. In 52 BD-IPMN with more than one examination only 6 lesions showed increase of ≥ 2mm. In 29 cases, a histopathological diagnosis was available after surgical resection. 27.6% of the patients who had surgical resection had high-grade dysplasia or cancer. The pre-operative EUS diagnosis was correct in 27.6%. The correct preoperative differentiation between mucinous and non-mucinous lesions was possible in 73.3%. The European Consensus Guidelines’ list of risk criteria showed to be a very sensitive (100%) and specific (93.5%) predictor of malignancy. No cystic lesion without an indication for resection showed malignant transformation during the mean observation period of 15.5 months (range 1 - 62).

Conclusions Pancreatic cystic lesions showed a very low rate of progression or malignant transformation during the first 5 years of observation. EUS alone shows a moderate accuracy to differentiate between serous and mucinous cystic neoplasia. Our results support surveillance for patients who are fit for surgery following the European Consensus Guidelines.