Comparison of Duodenal Stenting vs Transpyloric and Duodenal Stenting for Malignant Obstruction
Phase: NA
Conditions: Duodenal Obstruction
Sponsor: Medical College of Wisconsin

Title of trial: Comparison of Duodenal Stenting vs Transpyloric and 
Duodenal Stenting for Malignant Obstruction 
 
NCT #: NCT03125148 
 
Date of Document: March 17, 2017 

STUDY PROTOCOL 
 
Title: Comparison of Duodenal Stenting vs Trans-pyloric and Duodenal Stenting for Malignant 
Obstruction 
Principle Investigator: Kulwinder Dua 
Primary Contact: Amar Dodda 
 
Purpose: 
Enteral self-expanding metal stents (SEMS) are routinely used to palliate malignant gastric 
outlet obstruction (pancreas cancer, duodenal cancer, gastric cancer and metastasis) in patients 
not fit for surgical bypass. The technical success in placing these stents approaches ~100% and 
many of these procedures can be performed in an outpatient setting. However, the functional 
success (patient's ability to eat after stenting) is much lower than the technical success. One of 
the major reasons for this discrepancy is these patients are on narcotics which are known to be 
associated with poor gastric motility. At the discretion of the endoscopist, FDA approved enteral 
stents are placed either completely within the duodenum bridging the obstruction or placed 
across the pyloric opening besides bridging the duodenal obstruction.  
The significance of this study is to determine if trans-pyloric extension of an intra-duodenal stent 
facilitates better gastric emptying compared to an intra-duodenal stent without trans-pyloric 
extension. 
Background: 
No studies have shown whether duodenal stenting by itself or duodenal stenting with trans-
pyloric extension is superior in patients with duodenal obstruction secondary to malignancy. In 
one study, refractory gastroparesis secondary to benign etiologies (idiopathic, diabetes, and 
post-surgical) was managed with endoscopic trans-pyloric stent placement. In this study, clinical 
response was observed in 75% of patients. There was a predominant response in the patient's 
symptoms of nausea and vomiting. Gastric emptying studies were done post-stenting which 
showed the mean 4-hours gastric emptying normalized in 6 patients and significantly improved 
in 5 patients. In light of the success of trans-pyloric stenting in the setting of refractory 
gastroparesis due to benign pathology, we hope to show the same level of effectiveness in the 
setting of malignancy for which these stents are approved by FDA. 
Hypothesis: 
Enteral self-expanding metal stents deployed across the malignant duodenal obstruction with 
trans-pyloric extension will facilitate better gastric emptying and thereby better symptom relief 
compared to enteral self-expanding metal stents deployed completely within the duodenum. 
 
 
 

Aims/Objectives: 
The objective of this study is to compare symptom relief and gastric emptying in the following 
two groups of patients with malignant gastric outlet obstruction who have enteral self-expanding 
metal stents deployed 1) across the malignant duodenal obstruction with trans-pyloric 
extension and 2) enteral self-expanding metal stents deployed completely with the duodenum 
without trans-pyloric extension 
Recruitment Methods:  
Inpatients and outpatients referred to the Gastroenterology service at Froedtert Hospital for 
placement of enteral stents for palliation of malignant duodenal obstruction will be recruited as 
per the below inclusion and exclusion criteria. These patients are generally directly referred to 
the advance endoscopy faculty or are referred through the GI consult service. 
Inclusion Criteria 
• 
Confirmed diagnosis of cancer 
• 
Evidence of a single small bowel obstruction 
• 
Considered palliative (can be on narcotics, chemotherapy, and/or radiation therapy) 
• 
Not a surgical candidate 
• 
>18 years of age 
• 
Able to give consent 
• 
Eligible for endoscopy (medically fit) 
• 
Able to traverse past obstruction with a guidewire 
Exclusion Criteria 
• 
<18 years of age 
• 
Unable to give consent 
• 
Pregnant 
• 
Have evidence of multiple sites of obstruction in the small bowel 
• 
Have evidence of duodenal obstruction secondary to gastric cancer 
• 
Ineligible for endoscopy (due to comorbidities or acuity of illness) 
• 
Unable to traverse past obstruction with a guidewire 
Methods/Procedures: 
This is a prospective chart review study. All the procedures are being done for clinical 
indications. Since patients will be randomized to group A or Group B as below, a consent form 
will be used. 
• 
Prospectively enroll patients based on inclusion-exclusion criteria. 
• 
Stent deployment completely intra-duodenal vs with trans-pyloric extension based on 
randomization. 
• 
Computer-generated randomization will be conducted. We expect to randomize 20 
patients each to either complete intra-duodenal stenting (Group A) or with trans-pyloric 
extension (Group B). 

• 
Symptoms of gastric outlet obstruction: heartburn, chest pain, regurgitation, bloating, 
belching, fullness after meals and epigastric pain will be collected from chart review prior 
to the procedure and post procedure as recorded during follow-up clinic visits. 
• 
Medical record review of post-stent deployment (24-48 hrs post-deployment to allow for 
full expansion of the stent) gastric emptying studies. 
• 
Solid and liquid T1/2 will be compared between these 2 groups using statistical analysis. 
• 
An interim statistically analysis will be performed to determine if we need to study more 
patients. 
Statistics: 
We plan to study 40 patients prospectively (20 in each arm) and then using statistical software, 
conduct an interim analysis to determine if more patients are required. Solid and liquid T1/2 
times will be compared between 2 groups using an unpaired T-test. 
Risks to Participants 
Patient will incur no additional risks associated with extending a stent trans-pyloric as opposed 
to leaving the stent completely intra-duodenal. Both these approaches are currently being 
practiced without any studies showing one approach being better or worse than the other. Also, 
patient’s private and confidential information may be breached in case the data is accessed by 
an unauthorized person. In order to deal with this risk of confidentiality, the following measures 
will be taken: 
• 
Personal identifying information will be available only to Dr. Dua and authorized study 
staff who are officially part of the study. 
• 
Additionally, any paper forms will be kept in a locked cabinet at the gastroenterology 
department at MCW where the PI and research team members have access to the 
computer. The computer is password protected and only research members will have 
access to it. Any paper forms will be kept in a locked cabinet in the GI department. 
• 
Once the data is complete from MCW, the data will be stored in an excel spread sheet 
that is password protected. The data will be stored for the duration of the study and 
analysis, and once the study is completed, all the de-identified data will be stored for no 
more than 10 years.  
• 
Only Dr. Dua and other authorized personnel will have access to the study folder.  
Consent Process 
The study will be described in detail to the patient by the principal investigator or member of the 
study team who is familiar with the project. Perceived risks and benefits of the study will be 
described in detail. All patient question will be answered. The patient will be asked to sign a 
written informed consent document for the study. Consent can occur in two settings. If the 
patient is admitted, physical contact with the patient will occur with in person consent being 
obtained. If the patient is to be done as an outpatient, the patient will be consented on the day of 
the procedure. Patient will be given enough time (at least a minimum of 15 minutes) to read the 
consent form and ask any questions. Study procedures can begin as soon as the consent is 
signed. Each subject will have the opportunity to decline participation in the study at any time, 
and will be assured that declining to participate will have no effect on their future medical care. 
The primary language spoken by participants will be English. 

References: 
1. Mouen A. Khashab, Sepideh Besharati, et al. “Refractory gastroparesis can be successfully 
managed with endoscopic transpyloric stent placement and fixation (with video).” 
Gastrointestinal Endoscopy. 2015 Dec; 82(6): 1106-9. 
2.  Ahn HS, SJ Hong, et al. “Uncovered self-expandable metallic stent placement as a first-line 
palliative therapy in unresectable malignant duodenal obstruction.” Journal of Digestive 
Disease. 2012 Dec; 12(12): 628-33. 
3. Larssen L, T Hauge, AW Medhus. “Stent treatment of malignant gastric outlet obstruction: the 
effect on rate of gastric emptying, symptoms, and survival.” Surgical Endoscopy. 2012 Oct; 
26(10): 2955-2960. 
4.  Chandrasegaram MD, Eslick GD, et al. “Endoscopic stenting versus operative gastrojejunostomy 
for malignant gastric outlet obstruction.” Surgical Endoscopy. 2012 Feb; 26(2):323-9. 
5. Kobayashi S, Ueno M, et al. “Duodenal stenting followed by systemic chemotherapy for patients 
with pancreatic cancer and gastric outlet obstruction.” Pancreatology. 2016 Nov-Dec; 16(6): 
1085-1091. 
6. Hamada T. Hakuta R, et al. “Covered vs uncovered metal stents for malignant gastric outlet 
obstruction: a systematic review and meta-analysis.” Digestive Endoscopy. 2016 Dec 20. 
 
Appendix I: Data Collection Form 
 
Data Sheet 
De-Identified #: _______ 
 
A. Demographics 
 
Gender:      M      F 
 
Age: ______    
BMI: ________ 
B. Primary Diagnosis causing duodenal obstruction: 
 
 
____  Pancreatic Cancer 
____ Duodenal Cancer 
____ Lymph Nodes 
____ Metastatic Disease 
____ Other 
C. Diabetes: 
 
____ Yes 
____ No 
 
D. Cancer therapy (currently/on-going):  
 
____ Chemotherapy   
____ Radiation 
 
 
 

E. Narcotics: 
 
____ Yes 
____ No 
If yes:  Name__________________ Dose_____________ 
 
 
 
 
Morphine Equivalent _____________________ 
F. Pre-Procedure Symptoms (circle all that apply): 
 
Heartburn   
Chest Pain 
Regurgitation    Bloating 
Belching 
 
 
Post-prandial fullness  
Epigastric pain 
 
G. Stent Placement: 
 
Date of Procedure: __________________ 
Attending: _________________ 
Successful: 
 
 
____ Yes 
____ No 
Randomization Group: 
____ A 
____ B 
Full Expanded (within 48hrs) ____ Yes 
____ No 
H. Gastric Emptying 
 
Date of Exam:________________ 
 
 
 
T 1/2 (half time for gastric emptying): ______ 
 
% retained @1hr _____ 
B1 (slope of 1st phase of emptying): ______  
 
% retained @2hr _____ 
B2 (slope of 2nd phase of emptying): ______ 
 
% retained @3hr _____ 
C (time for when slope changes from B1 to B2): ______ 
% retained @4hr _____ 
Overall interpretation: 
_____________________________________________________ 
 
I. Post Procedure Symptoms (circle all that apply) 
 
Heartburn : 
Better  Same  Worse      
Chest Pain:  
Better  Same  Worse 
 
Regurgitation: Better  Same  Worse     
Bloating:  
Better  Same  Worse 
 
Belching:  
Better  Same  Worse  
Post-prandial fullness : Better/same/ Worse  
 
Epigastric pain: Better  Same  Worse