S3336 Individualizing Treatment for Branched Duct Intraductal Papillary Mucinous Neoplasms (IPMN)

Abstract

INTRODUCTION: Pancreatic cysts may be detected in 40-50% of patients who undergo abdominal imaging for non-pancreatic indications. Some cysts have significant malignant potential and should be resected; however, most are benign or have low malignant potential. Since, surgery is associated with high mortality and morbidity, guidelines having been outlined to direct management based on imaging parameters. These have helped to identify high risk features, avoid unnecessary resection and plan a cost-effective surveillance algorithm. As per current guidelines, IPMN or mucinous cystic neoplasms (MCN) with mural nodule or solid components, IPMN involving main duct, and IPMN more than 3 cm in size require resection. We present a case of IPMN of branch duct of 2.5 cm in size. Based on history and prior imaging patient was sent for resection even though she did not meet the criteria. It turned out to be IPMN with high-grade dysplasia. CASE DESCRIPTION/METHODS: A 73 y/o female’s ultrasound showed cholelithiasis and two hypoechoic foci 1.7 cm in size in the pancreatic tail. Similar findings were not found on CT scan done a year ago. MRI revealed pancreatic body cystic lesion 2.5 × 1.5 cm in size that communicated with the main pancreatic duct. The cyst could also lie within the duct as there was diffuse contiguous dilation in the tail region measuring up to 5 mm. Due to high suspicion that it was malignant, patient was referred for resection. DISCUSSION: 90% of Pancreatic Cystic Neoplasm (PCN) are serous cystadenoma, MCN and IPMN. Most are IPMN of the branched duct that have a very low rate of malignant transformation (unlike the main duct that have a 60% rate). They are usually complex cysts that communicate with the main duct. They undergo surveillance with frequency depending on cyst size. Resection is recommended for cysts more than 3 cm in size. We strongly recommend for consideration of other attributes, including history and physical exam, to individualize treatment decisions. Our patient had no cyst in prior imaging which suggested a rapid increase in size. There was a 5 mm focal dilation of the main duct; hence there remained a possibility for its involvement. It was referred for resection. CONCLUSION: The clinical scenario presented above was not addressed by the current guidelines for IPMN management. It is imperative to individualize patient care, tailor the algorithm, and incorporate variations in current guidelines after clinical studies. This can help us identify early cancer and reduce death.