Pancreatic Cysts

Question 1

What are pancreatic cysts?

Answer 1

Pancreatic cysts are collections of fluid that form within the pancreas.

Question 2

Give examples of high risk pancreatic cysts

Answer 2

• Intraductual Papillary Mucinous Neoplasm
• Mucinous Cystic Neoplasm
• Solid Pseudopapillary Neoplasm
• Cystic Pancreatic Neuroendocrine Tumour

Question 3

Give examples of low risk pancreatic cysts

Answer 3

• Serous Cystic Adenoma
• Simple Cyst
• Mucinous Non-Neoplastic Cyst
• Lymphoepithelial Cyst

Question 4

What are the clinical features of pancreatic cysts?

Answer 4

In 70% of cases, pancreatic cysts are asymptomatic, found incidentally on imaging.

For symptomatic cysts, presenting complaints include abdominal pain or back pain (from mass effect and compression symptoms), post-obstructive jaundice or vomiting.

Cysts can become infected and present with systemic features. Those that become malignant and metastasise may present with systemic features of malignancy (weight loss, loss of appetite, change in bowel habits etc.)

Examination will likely be unremarkable; in rare occasions, there may be a tender abdomen, a palpable mass, or abdominal distension.

Question 5

What investigations should be ordered for pancreatic cysts?

Answer 5

As suggested, most cases are picked up via imaging, however those cases being worked up for further management may warrant baseline blood tests, including FBC, U&Es, and LFTs. A CA 19-9 level can be helpful to monitor progression of the disease.

Current NICE guidelines suggest pancreatic protocol CT scan or magnetic resonance cholangiopancreatography to further assess and evaluate pancreatic cysts.

Based on the features identified on initial imaging, further investigation may be warranted, either via complete resection (especially if high risk) or further testing through Endoscopic US scan with Fine Needle Aspiration (EUS-FNA). EUS- FNA allows for a biopsy sample to be obtained, which is useful in determining both low and high grade lesions.

Question 6

Briefly describe the management of pancreatic cysts

Answer 6

Most pancreatic cysts will be discussed at the multidisciplinary team (MDT) meetings, to plan for any further imaging, follow-up, or surgical intervention warranted. The majority of pancreatic cysts are benign and can therefore be left alone with surveillance only.

In high-risk cysts, resection should be the first line of treatment, where feasible.

In those with low risk cysts, surveillance is recommended every 5 years, as the risk of malignant transformation is so low (put at 0.24% per year).

Question 7

Briefly describe the prognosis of pancreatic cysts

Answer 7

The prognosis of these patients is highly dependent on subtype of the cyst and degree of invasion. Non-malignant and non-invasive cysts will have excellent prognosis, however malignant and invasive cysts have a significantly worse survival of 60% at 5-years, despite treatment.

Question 8

Compare and contrast the features of a low and high risk cyst

Answer 8

Low risk features

• Cyst diameter <3cm
• Cystic morphology with central calcification
• Asymptomatic

High risk features

• Cyst diameter >3cm
• Main pancreatic duct dilatation greater than 10mm
• Enhancing solid component
• Non-enhancing mural nodule

Question 9

What differentials should be considered for pancreatic cysts?

Answer 9

• Pancreatic pseudocyst

Question 10

What is a pancreatic pseudocyst?

Answer 10

This is a collection of fluid within the pancreatic tissue, typically forming following pancreatitis; the inflammatory reaction produces a necrotic space in the pancreas that fills with pancreatic fluid, however this lacks epithelial or endothelial cells surrounding the collection so is termed a pseudocyst. Pseudocysts are also commonly asymptomatic, so tend to be picked up on imaging.