Pancreatic cysts are increasingly found during abdominal imaging. Although the majority will not cause any problems, a minority may enlarge or become malignant. We present a contemporary approach to managing pancreatic cysts, utilizing the latest evidence, technologies and endoscopic procedures. We identify which cysts need surveillance or even surgery, and which can be safely ignored.

1. Pancreatic Cysts
A Contemporary Approach
Dr Jarrod Lee
Gastroenterologist

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3. What has Changed?
• Dramatic increase in numbers recently
– Most detected incidentally
– Prevalence in literature varies widely:
• 0.2% on screening US
• 2.5% on screening CT
• 14-20% with incidental findings on MRI studies
• Up to 25% in autopsy studies
• New literature
– Understanding natural history
– Role of Endoscopic Ultrasound (EUS)
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Classification

5. Serous Cystadenoma (SCN)
• Benign, but can grow
• 3 morphological patterns: Polycystic, honeycomb, oligocystic
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6. Mucinous Cystadenoma (MCN)
• 2 components by definition
– Mucin producing epithelium
– Dense ovarian stroma subjacent to epithelium
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7. Intraductal Papillary Mucinous Neoplasm
• 3 types of IPMN:
– Main duct (MD-IPMN)
– Branch duct (BD-IPMN)
– Mixed
• MD-IPMN
– segmental or diffuse MPD dilation > 5mm without other
cause of obstruction
• 70% correlation between radiology and histology
– Classification should be based on pre-operative
assessment
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8. MD-IPMN
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BD-IPMN
Mixed

9. Evaluation
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10. Further Evaluation
• Why evaluate?
• Look for ‘high risk stigmata’ or ‘worrisome features’
• When to evaluate?
– Symptomatic cysts
– When cyst > 1cm
• Cyst < 1cm
– Risk of cancer very low
– No evaluation needed, only surveillance
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11. How to Evaluate?
• MDCT or MRI-MRCP
• EUS
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12. Worrisome Features
High risk features
• MPD > 9mm
• Obstructive jaundice
• Enhancing solid
component
Resection Indicated!!
Worrisome Features
• MPD dilation 5-9mm
• Cyst > 3cm
• Non enhancing mural nodules
• Thickened enhanced cyst wall
• Abrupt change in MPD calibre
with distal pancreatic atrophy
• Lymphadenopathy
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13. Distinguishing the Cysts
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14. Surgical Resection
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15. Indications for Resection
• Recommended for all MD-IPMN and MCN if
surgically fit
• MD-IPMN
– Mean frequency for malignancy 61.6%
– No consistent predictors for malignancy
• MCN
– Prevalence of invasive cancer < 15%
– No malignancy if < 4cm without mural nodules
– Given relatively young age and common location in body
or tail, resection usually recommended
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16. How about BD-IPMN?
• Mean frequency of malignancy 25.5%
• Annual malignancy rate 2-3%
• 24-41% are multifocal, but approach same as
unifocal BD-IPMN
• Occurs mostly in elderly
– Supports conservative management if no risk factors for
malignancy
• Younger patients with cyst size > 2cm may be
candidates due to cumulative risk of malignancy
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17. Surveillance
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18. IPMN
• Little evidence to guide
• Need to individualize based on risk: benefit
• Baseline: MRI/MRCP + EUS
• No high risk stigmata
– Undergo short interval 3-6mth surveillance to
establish stability
– Thereafter survey according to size
• High risk stigmata: offer resection
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19. Post Resection
• MCN:
– Almost always solitary, complete resection curative
– No post surgery surveillance
• IPMN
– May persist:
• BD-IPMN left unresected
• Surgical margins have residual IPMN
• New lesions in remnant pancreas
– 6 months surveillance interval
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20. Endoscopic
Ultrasound
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21. Why EUS?
Advantages
• Increased resolution
• Real time imaging
• Allows cyst fluid aspiration
Results in:
• Better assessment of morphology
• Better detection of worrisome symptoms
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22. ‘Classic’ SCN
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23. ‘Classic’ MCN
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24. MD IPMT
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PD
Cyst

25. Simple Cyst ? Branch Duct IPMN
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26. Cyst Fluid Analysis
• CEA
– Most frequently used to distinguish mucinous and non-
mucinous cysts
– CEA > 192 ng/ml has 73% sensitivity and 65% specificity
– Cannot distinguish IPMN and MCN
– Cannot distinguish benign and malignant cysts
• Amylase
– Raised in mucinous cysts (IPMN and MCN)
– Also raised in pseudocysts
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27. Molecular Markers
• KRAS mutations & microsatellite markers
– Found to correlate with degree of dysplasia in cysts
– Multicentre trial (PANDA study): > 65% predictive of
mucinous lesion
– Not predictive of malignancy
• MicroRNA expression profiles
– Aberrant expression associated with pancreatic cancer
– ? Potential tool in future
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28. Main Problems
• Inadequate sample
• Sampling error in septated cyst
• Contamination by gastric or duodenal mucosa
• Spillage and seeding?
• Cyst aspirate often lacks cellularity
– Personal experience (last 100 EUS-FNA)
• Pancreatic mass: 99% yield
• Pancreatic cysts: <20% cellular yield
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29. Contrast Enhanced EUS (CE EUS)
• Contrast agents
– Gas containing microbubbles encased in a resistant shell
– Oscillate when hit by an ultrasound wave to produce an
acoustic ‘enhancement’ signal
• Allows micro-vessels and parenchymal perfusion to
be visualized
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30. CE EUS in Pancreatic Cysts
• Can differentiate cystic neoplasms from pseudocysts:
contrast enhancing effect within cystic structures
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Mural
Nodules

32. Confocal Laser Endomicroscopy (CLE)
• Allows real time histological
assessment during endoscopy
– Probe or endoscope based
– Can apply anywhere in GI tract
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33. EUS Guided
Confocal
Microscopy
• Initial studies for pancreatic cystic neoplasms:
– Sensitivity 59%; Specificity 100%
– PPV 100%; NPV 50%
– Complications 9%: pancreatitis, transient pain, bleeding
• Limitation: diagnostic yield
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34. SCN
• Vascular network of branch vessels
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35. IPMN
• ‘Finger like projections’ intestinal papillae
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36. EUS Guided
Cyst Ablation
• Developed as an alternative to surgery
– Safe, minimally invasive
– Useful in poor surgical candidates
• Cyst ablation effective in kidney, liver, thyroid
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37. Ablative Agents
• Ethanol
– Low viscosity, easy to inject
– Induces cell membrane lysis, protein denaturation,
vascular occlusion in 10 min
– Penetrates fibrous capsule slowly
• Paclitaxel
– Chemotherapeutic agent, inhibits microtubule processes
– Hydrophobic and viscous, can exert a durable effect on
cyst epithelium with low risk of leak
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38. Technique
• Cyst aspiration allows space for ablative agent
• Total injection volume should not exceed aspirated
volume to avoid leakage and parenchymal injury
• Contrast enhancement EUS improves visualization
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39. Outcomes
• Short term resolution rates: 33-70%
• No recurrence for median of 26 months
• Complications:
– Abdominal pain <10%, pancreatitis 2%
– Rare: cyst spillage, portal or splenic vein thrombosis
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41. Ideal Cyst for Ablation?
• Preferred candidates
– For those with high surgical risk or refuse surgery
– Cyst > 2cm
– Unilocular or oligo-locular with < 3 locules
– No communication with MPD
• Preferred cyst: MCN
• Consider for: BD-IPMN, growing macrocystic SCN
• Promising, but concerns exist
– Long term durability and follow up
– Optimal agent? Protocol?
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2012 International Consensus Guidelines

43. • High risk features
– PPV 62.5%
– NPV 100%
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Advanced Endoscopy

45. Thank You
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Questions?
drjarrodlee@gmail.com