Introduction A dilated Pancreatic Duct (PD) may be associated with pancreatic disease, but this is infrequently investigated further if no lesion is found on Computerised Tomography (CT). There is limited data on the role of Endoscopic Ultrasound (EUS) with PD dilatation without a cause on CT, as the literature mostly describes the utility of EUS with apparent pancreatic lesions. We describe our experience of EUS in identification of causative lesions not apparent on CT.

Methods Sixty-one (61) cases were identified and retrospectively reviewed between 2007–2013 by searching the EUS database at a university teaching hospital. All had CT +/- MRCP findings of dilated PD (+/- Common Bile Duct (CBD) dilatation) and no pancreatic lesion (54 patients) or oedema/unable to exclude a lesion (7).

Results Mean patient age was 70 (41–90). Indications for CT included abdominal pain 16; abnormal Liver Function Tests (LFT) 14 (3 jaundiced); weight loss 9; other 14 (eg. staging CT for lung ca, CT colonography for diarrhoea etc). Mean PD diameter was 6 mm (3–25 mm) and 30 had CBD dilatation. CT showed normal pancreatic parenchyma in 46 (76%); prominent ampulla 5 (8%); pancreatic cyst 5 (8%), calcification 4 (6.5%); pseudocyst 1 (1.5%). After EUS, 49 (80%) had PD dilatation confirmed, whilst 31 (51%) also had CBD dilatation. 38 (62%) failed to identify a cause and hence agreed with CT. Of the remaining 23 (38%) there was disparity between CT and EUS. An FNA biopsy was performed in 16 (26%) of cases. Findings included neoplasm 9 (15%); IPMN 4 (6.5%); biliary stone disease 3 (5%); chronic pancreatitis 3 (5%); pseudocyst 1 (1.5%); choledochal cyst 1 (1.5%); and pancreas divisum 1 (1.5%). Neoplastic disease included pancreas cancer 5; suspicious ampullary tumour 2; cholangiocarcinoma 1; and mucinous cystadenoma 1. With particular reference to EUS, there was isolated PD dilatation in 27 cases (44% of total), and abnormalities detected in (59%) which included cancer or IPMN (15%). In PD and CBD dilatation 22 (36%); 6 cases were abnormal of which 4 (18%) had cancer (pancreas and ampulla). Without PD dilatation 12 (20%), pathology was found in 50% including cholangiocarcinoma (1), IPMN (1), CBD stones (3), chronic pancreatitis (1). Of 9 cancer patients, dilatation was seen in PD only (4); PD and CBD (4); normal PD or CBD (1).

Conclusion PD dilatation should be investigated further with EUS, even when CT shows no causative lesion. We identified a significant percentage of benign (21%) and malignant (15%) pathology with EUS. EUS offers the additional advantage of biopsy when there is diagnostic doubt. Normal LFTs and the absence of the ‘double duct sign’ are insufficient to exclude neoplastic disease and EUS will help identify these.

Disclosure of Interest None Declared.