What are the causes of a dilated pancreatic duct?

From the Guidelines

A dilated pancreatic duct can be caused by several conditions that obstruct pancreatic fluid flow, with the most common causes including pancreatic cancer, chronic pancreatitis, intraductal papillary mucinous neoplasms (IPMNs), and ampullary stenosis, as well as pancreas divisum, which is a congenital anomaly where the dorsal and ventral pancreatic ductal systems fail to fuse, leading to impaired drainage of pancreatic secretions 1.

Common Causes of Dilated Pancreatic Duct

• Pancreatic cancer, particularly adenocarcinoma of the pancreatic head, frequently causes duct dilation by directly compressing the duct
• Chronic pancreatitis leads to dilation through inflammation, fibrosis, and stricture formation
• IPMNs are cystic tumors that arise from the pancreatic ducts and produce mucin that can obstruct flow
• Ampullary stenosis can also cause dilation by obstructing the flow of pancreatic secretions
• Pancreas divisum, a congenital anomaly, can lead to impaired drainage of pancreatic secretions, potentially resulting in increased intraductal pressures, which may precipitate recurrent acute pancreatitis (RAP) 1

Evaluation and Treatment

• Evaluation typically requires imaging such as CT, MRI/MRCP, or endoscopic ultrasound, often followed by ERCP for both diagnosis and potential intervention
• The treatment depends on the underlying cause, ranging from endoscopic stenting for benign strictures to surgical resection for malignancies
• Patients with dilated pancreatic ducts may present with abdominal pain, jaundice, weight loss, or be completely asymptomatic, with the finding discovered incidentally on imaging

Specific Considerations for Pancreas Divisum

• Endoscopic therapy for symptomatic pancreas divisum aims to relieve outflow obstruction by enlarging the minor papilla, which can be achieved through minor papilla sphincterotomy, balloon dilation, stent placement, or some combination thereof 1
• High-quality studies supporting endoscopic therapy in patients with pancreas divisum and RAP are lacking, but data from retrospective uncontrolled studies suggest that endoscopic intervention may reduce or eliminate episodes of RAP 1

From the Research

Etiology of Dilated Pancreatic Duct

• The etiology of a dilated pancreatic duct can be attributed to various factors, including pancreatic duct strictures, malignancy, and chronic pancreatitis 2, 3, 4, 5, 6
• Pancreatic duct strictures can be caused by benign or malignant conditions, and the treatment approach varies depending on the underlying etiology 2
• Chronic pancreatitis is a common cause of pancreatic duct strictures, and endoscopic treatment with stent placement is a frequently used approach 4, 5, 6
• Malignancy, such as pancreatic cancer, can also cause a dilated pancreatic duct, and the diagnosis is often made using imaging studies and endoscopic ultrasound-fine-needle aspiration 3

Diagnostic Approaches

• Imaging studies, such as computed tomography and magnetic resonance imaging, can be used to diagnose a dilated pancreatic duct and identify potential causes 3
• Endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound-fine-needle aspiration (EUS-FNA) are also useful diagnostic tools for evaluating pancreatic duct strictures and malignancy 2, 3, 4, 5, 6

Treatment Options

• Endoscopic treatment with stent placement is a common approach for managing pancreatic duct strictures, including those caused by chronic pancreatitis and malignancy 2, 4, 5, 6
• Surgical intervention may be necessary in some cases, such as when endoscopic treatment is not effective or when a malignant tumor is present 2, 6
• Fully covered self-expanding metal stents (FC-SEMSs) and biodegradable stents are also being used to treat pancreatic duct strictures, with promising results 4, 6