Abstract
A 78-year-old male presented after a cystic lesion in the pancreatic body was found on plain CT scan. MRCP revealed a dilated branch appearing like a "bunch of grapes" 20mm in size and a localized stenosis of the main pancreatic duct (MPD) in the surrounding area with mild proximal dilation. The delayed phase on contrast-enhanced (CE) CT scan exposed a faint hyper-attenuated area around the MPD stricture and dilated branch. ERP revealed a dilated branch connected to the MPD containing mucin. Pancreatic juice cytology showed atypical cells suggesting adenocarcinoma. The patient underwent distal pancreatectomy because of suspicion for invasive intraductal papillary-mucinous carcinoma (IPMC) or concomitant ductal carcinoma of the pancreas. The pathological diagnosis was mixed-type IPMC, non-invasive. Enhanced images on the CE-CT scan were presumed to have shown a fibrotic area around the tumor. There are reports that a hypoechoic area on EUS suggests non-invasive carcinoma, related to fibrosis around affected ducts. They have attracted attention as being important indirect observations of the tumor. However, there are few reports of fibrosis detected on CT scan so far. This is a clinically significant case where fibrosis around pre-invasive IPMC was detected as focal faint enhancement by CE-CT scan.
