Endoscopic Ultrasound (EUS) has advanced rapidly in recent years, and has evolved from a primarily diagnostic tool, to one that has an increasing role in interventions. We review the latest roles of EUS guided interventions for pancreas and bile duct tumours. The lecture was the plenary lecture at the Philippines National Endoscopy Conference 2014

1. EUS Guided Interventions for
Pancreatobiliary Tumours
Dr Jarrod Lee
Gastroenterologist @ Mount Elizabeth Novena Hospital
2014 PSDE Live Endoscopy Workshop

2. Interventional EUS
• EUS allows clear visualization of the GI luminal wall
and its adjacent structures
• Most adjacent structures can be reached by a needle
• This allows injection of drugs or passage of wire
• With a guidewire, tools and accessories can be
passed over wire
• Any structure visualized by EUS is a potential target
for intervention
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3. Scope
• Celiac Plexus Interventions
• Radiation Therapy
• Fine Needle Injection (FNI)
• Tumour and Cyst Ablation
• EUS guided biliary drainage (EGBD)
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4. Celiac Plexus Interventions
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5. Celiac Plexus Neurolysis (CPN)
• Injection of absolute alcohol to destroy the
sympathetic plexus at the celiac axis
– Relieves abdominal pain in 70-90% cancer patients
– Bupivacaine usually given first
• EUS guided CPN
– Provides direct real-time visualization of celiac plexus and
surrounding vessels
– Safer than trans-abdominal or posterior approaches
• Variants: CGN, BPN
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Celiac Plexus

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8. Outcomes & Safety
• CPN vs conventional pain management:
– CPN relieves refractory pain in 80%
– Early EUS-CPN provides greater pain relief than
conventional pain management
– CPN significantly reduces opioid consumption
• Complications
– Mild (up to 30%): diarrhea, hypotension, abdominal pain
– Serious (1-2%): Bleeding, abscess, ischemia, paralysis
– Paradoxical pain in up to 9%, but resolves over days
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9. Image Guided
Radiation Therapy
• Type of conformal radiotherapy, where radiation beams are
shaped around the cancer
• Accurate targeting and tracking during treatment allows high
doses and less side effects
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10. Fiducials
• Inert radiographic markers implanted to a tumour
target for IGRT
• EUS guided fiducial placement for pancreatic cancer
– High technical success > 90%
– Complications rare (<5%): mild pancreatitis, minor
bleeding, fiducial migration
– Placed through 19G or 22G needles
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12. Before
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After

13. EUS Guided Brachytherapy
• Involves places a radioactive seed directly into the
tumour for localized radiation therapy
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Iodine 125 is the most
commonly used seed
• Half life 60 days; tissue
penetration 1.7cm
• Can be inserted
through 19G needle

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15. 152 months later
Brachytherapy Results
• 3 case series to date
• 100% technical success
• No complications
• Partial response limited (<27%)
• No survival benefit
• Pain response dramatic > 80%

16. Fine Needle
Injection
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17. Fine Needle Injection (FNI)
• Direct delivery of therapeutic agents into pancreatic
tumours under EUS guidance
• Allows high doses of therapeutic agents whilst
minimizing systemic side effects
• Many agents studied
– Various onco-viruses, chemotherapeutics, immune cells
– Results mixed
– No agent with efficient tumour killing effect
– Side effects can be considerable
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18. Studies to Date
No suitable agent found yet; studies on-going
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EUS Guided
Tumour Ablation

20. EUS Guided Tumour Ablation
• Radiofrequency Ablation (RFA)
– Causes local thermal induced coagulative necrosis
– Animal studies show it is feasible, effective and safe
• Cryothermal Ablation (CTA)
– Alternates fixed heating with cooling
– 1 case series: technical success in 72.8%; no complications
• Photodynamic Therapy (PDT)
– Produces local tissue necrosis with light after applying a
photosensitizing agent (concentrates in malignant tissue)
– Feasible in animal trials
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21. Cryothermal
Ablation
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Pancreatic Cysts

23. Why EUS?
Advantages:
• Increased resolution
• Real time imaging
• Allows cyst aspiration
Results in:
• Better assessment of morphology
• Better detection of worrisome features
• Analysis of cyst fluid
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24. 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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25. 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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26. 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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27. 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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29. 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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EUS Guided
Biliary Drainage

31. ERCP Failures in Pancreatobiliary Tumours
• Failed ERCP
– ERCP cannulation fails in 10%
– Higher fail rates in pancreatobiliary tumours
– Alternate access: pre-cut sphincterotomy, PTBD
(percutaneous transhepatic biliary drainage)
• Higher fail rates in pancreatobiliary tumours
– Biliary strictures
– Distorted anatomy or ampulla
– Gastric outlet obstruction
– In situ enteral stents
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32. EUS Guided Biliary Drainage (EGBD)
• Uses same general concepts as EUS guided
pseudocyst drainage
– Smaller targets
– Higher risk of leaks and complications
• Overall success 80-90%; complication rate 20-25%
• Approaches:
1. Transpapillary rendezvous approach
2. Direct transluminal approach
A. Choledocho-duodenostomy (CDS)
B. Hepatico-gastrostomy (HGS)
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33. Rendezvous
Technique
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34. Transpapillary Rendezvous Approach
• Can only be done if papilla accessible by endoscopy
• Guidewire manipulation is most challenging aspect
• Advantage:
– Lower complication rates: 10%
• Disadvantages:
– Higher failure rate: 20%
– Has longer procedure time
– May lead to acute pancreatitis
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35. Direct Transluminal Approach
• Advantages:
– Higher success rates: 85-95%
– Shorter procedure times
– Hepatico-gastrostomy (HGS) can be done in patients with
duodenal obstruction or previous gastric surgery
• Disadvantages:
– Higher complication rate: 15-30%
– Rare but serious adverse events : stent migration or
occlusion, bile leak, bile peritonitis, cholangitis, hemobilia,
pneumoperitoneum
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36. Choledocho-Duodenostomy (CDS)
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37. Hepatico-Gastrostomy (HGS)
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38. EUS-HGS in Gastric
Outlet Obstruction
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39. Various Approach Routes
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40. What does the Evidence Say?
• EGBD vs PTBD (LE Ib)
– No difference in success rates, complications or cost
• EGBD vs Precut papillotomy (LE III)
– EGBD (rendezvous technique) superior success
– No difference in complications
• EGBD: rendezvous vs direct techniques (LE III)
– No difference in success or complications
• EGBD: transhepatic vs extrahepatic (LE III)
– Similar success rates
– Extrahepatic: shorter procedure time, less complications
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41. Take Home Message
• EUS has evolved from a
diagnostic tool to an
interventional platform
• EUS is an important modality in
the management of
pancreatobiliary tumours
• The future holds many exciting
prospects for interventional EUS
• Controlled trials are critical to
show which interventions will
become valuable
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42. Looking to
the Future
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Thank You