CT scan of a 58 year old male presenting with epigastric pain and weight loss. CT scan demonstrates a transverse diameter mass of 3 cm in the head of the pancreas (indicated by the black arrow). Also evident is dilation of the proximal main pancreatic duct and two areas of hypodensity (duller or darker patches) in the liver. Findings: Adenocarcinoma of the head of the pancreas. The patient underwent an ERCP (Endoscopic Retrograde Cholangiopancreatography) which is an investigation used to examine and diagnose diseases of the gallblader, bile system, pancreas and liver. The ERCP confirmed the presence of a distal pancreatic bile duct stricture and simultaneous dilatation of the main pancreatic duct.
Cancer of the pancreas can be divided into two main types which are Exocrine and Endocrine. The exocrine type is dominated by pancreatic adenocarcinoma (as demonstrated in image 1 above) and is by far the most common pancreatic cancer accounting for around 85% of all cases.(1) An adenocarcinoma is a malignant tumour that is formed from glandular structures in epithelial tissue. In carcinoma of the pancreas it usually starts in the pancreatic ducts but sometimes can develop in the cells that make pancreatic enzymes in which case they are called ‘acinar cell carcinomas’. About 60-70% of adenocarcinomas are in the head of the pancreas and around 20-25% in the body or tail.
The ‘double duct sign’ is commonly caused by carcinoma of the head of the pancreas and refers to the presence of simultaneous dilatation of the common bile duct (CBD) and the pancreatic ducts (Image 2). It can be seen on most investigations that can visualise the region such as MRCP, CT, MRI and ERCP. When the tumour is located in the body or tail of the pancreas it causes upstream pancreatic duct dilation only (see Image 3).
MRCP Image demonstrating the ‘double duct’ sign. The pancreatic duct (indicated in this image by the long white arrow) is dilated and the common bile duct (indicated by the short arrow) is also dilated due to adenocarcinoma of the head of pancreas.
Image demonstrating adenocarcinoma in the body or tail of the pancreas. The short arrow illustrates the upstream pancreatic duct dilation due to adenocarcinoma indicated by the long arrow.
Pancreatic Cancer in General
Pancreatic cancer often has a poor prognosis due to the fact that often, in the early stages of the disease, there are no symptoms. By the time that symptoms indicative of pancreatic cancer appear (such as pain in the abdomen or back region, jaundice, dark stools and urine and weight loss), the disease has often advanced and spread to other areas of the body. (2) Over 90% of pancreatic cancers are diagnosed in the late stages of the disease. More than 80% of pancreatic cancers are diagnosed in people aged 60 and over. Pancreatic cancer is uncommon in people under 40 years of age with the average age at diagnosis being 71 years old. Pancreatic cancer is the twelfth most common cancer worldwide and approximately 338,000 new cases were diagnosed in 2012; this accounts for 2% of the total of all cancers.(3)
1. Ryan DP, Hong TS, Bardeesy N (September 2014). ‘Pancreatic adenocarcinoma’. N. Engl. J. Med. 371 (11): 1039–49.
2. World Cancer Report 2014. World Health Organization. 2014. pp. Chapter 5.7. ISBN 9283204298.
3. Cancer Research UK