When To Evaluate Pancreatic Cysts

It seems that pancreatic cysts are on the rise with more patients than ever finding that they have them hiding in their pancreas. This might not actually be the case - most tend to be incidentally found on imaging done for other purposes. As imaging techniques have evolved and patients have more (and higher resolution) images performed, we are bound to pick up other abnormalities as well. But how do you know if an incidental finding such as a pancreatic cyst is something to forget about or a serendipitous finding that should be evaluated further?

The reality is that the percentage of pancreatic cysts that harbor cancers are quite small. The challenge is figuring out which ones have a higher risk of progression to cancers in the future, so that they can be better monitored and intervened on if and when the time arises. I am specifically referring to cysts found in patient who have no symptoms; patients who are symptomatic require a more focused and expedited evaluation, and that discussion is beyond the scope of this article. Additionally if you have a family history of pancreatic cancer you should discuss options for screening with your gastroenterologist, and I will hopefully be posting an article discussing screening in that select population of patients in the near future.

There is a cyst found in your pancreas - how do you get more information?

Typically if we want a more comprehensive evaluation of a cyst, you will be referred for an Endoscopic Ultrasound (EUS) exam which is performed by a gastroenterologist, with Fine Needle Aspiration (FNA) of the cyst performed under ultrasound guidance - this is where a needle is introduced into the cyst to suction fluid out for analysis. An important piece of information to know about the test is that sampling the cyst is not the same as removing the cyst, which is a surgical procedure at this time.

So who would benefit from EUS exam?

In order to answer this question, guidelines were created to try and help doctors and their patients navigate this conundrum. The first guidelines published were by the American Society for Gastrointestinal Endoscopy (ASGE) in 2005. These guideline advocated for cyst fluid aspiration (suction) and evaluation for all cysts. In 2006 the International Association of Pancreatology (IAP) published what is known as the Sendai Guidelines which focused more on the size of the cyst and worrisome features - which I will explain further below - that can be found during exam. The IAP updated those guideline in 2012, focusing more on the “worrisome features” and less on cyst size. The American Gastroenterological Association (AGA) published the most recent recommended guideline in 2015. The AGA recommendations are the most conservative in regard to when to offer Endoscopic Ultrasound and sampling, and when to refer patients for surgery.

What do you mean by “Worrisome Features”?

• Cyst Size, typically larger than 3cm in diameter

• Dilation of the main pancreatic tube greater than 5mm in diameter

• Abnormalities of the cyst wall such as thickening

• Any solid areas within the cyst (known as “mural nodules”)

• Any abrupt change in the caliber of the pancreatic tube concerning for obstruction or impingement

• Cytology (the slides that the pathologist will look at under the microscope) that shows abnormality

There has been much talk in the literature in regard to which guideline to follow, as some are more conservative in their recommendations. As a community we are still trying to finetune the recommendations in order to best serve our patients - to highlight and intervene upon the patients who are progressing towards cancers, and equally as important to avoid surgical interventions in those patients who will not benefit from them.

If you have an EUS exam and Aspiration performed, your doctor should have a good idea of where the cyst falls within the guidelines. Your procedure report should comment on the presence or absence of some of the worrisome features of the cyst, as well as detailing the measurements. Once the fluid analysis and cytology have returned, your doctor can sit down with you and discuss a detailed plan regarding surveillance, surgery, or no need for surveillance at all.

To recap - most cysts are found incidentally at the time of imaging for other reasons. If you find a cyst and do not have any symptoms, discuss this with your gastroenterologist. They may decide that further evaluation with a EUS and Fine Needle Aspiration is warranted in order to decide together with you how aggressive you need to monitor the cyst in the future.

Photo Credit by Aaron Burden on Unsplash

References:

Jacobson B C, Baron T H, Adler D G et al. ASGE guideline: the role of endoscopy in the diagnosis and management of cystic lesions and inflammatory fluid collections of the pancreas. Gastrointest Endosc. 2005;61:363–370.

Tanaka M, Chari S, Adsay V et al. International consensus guidelines for management of intraductal papillary mucinous neoplasms and mucinous cystic neoplasms of the pancreas. Pancreatology. 2006;6:17–32.

Tanaka M, Fernandez-del Castillo C, Adsay V et al. International consensus guidelines 2012 for the management of IPMN and MCN of the pancreas. Pancreatology. 2012;12:183–197.

Vege S S, Ziring B, Jain R et al. American Gastroenterological Association institute guideline on the diagnosis and management of asymptomatic neoplastic pancreatic cysts. Gastroenterology. 2015;148:819–822.

McGrath K. Management of incidental pancreatic cysts: which guidelines? Endoscopy International Open. 2017;5(3):E209-E211.

DISCLAIMER: Please note that this blog is intended for Informational Use only and is not intended to replace personal evaluation and treatment by a medical provider. The information provided on this website is not intended as substitute for medical advice or treatment. Please consult your doctor for any information related to your personal care.