Review for 10.1186/s12876-018-0886-8 (2018)

Reviewer ’s report  
 
Title: Efficacy and safety of ch emotherapy after endoscopic double stenting for malignant 
duodenal and biliary obstructions in patients with advanced pancreatic cancer: a single -
institution retrospective analysis.  
 
Version: 2 Date: 05 Oct 2017  
 
Reviewer: Donald  Miller  
 
Reviewer's report:  
 
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This is a retrospective, single institution study of "double stenting" (stenting both biliary duct 
and duodenum) in patients with advanced nonresectable pancreatic cancer.  The authors  study 
the results of 50 patients who we re doubly stented, many of whom (21 -42%)subsequently 
received chemotherapy.  The authors report overall survival time and survival following stenting 
(2.4 months).  This manuscript addresses an important problem in the management of pancreatic 
cancer.  Bec ause of the relative ineffectiveness of chemotherapy for advanced pancreatic cancer, 
obstruction is a relatively common problem which can be difficult to manage.  There are several 
concerns about the data presented.  The authors discuss the issues of a ret rospective, single 
institution study.  The heterogeneity of the patient population, the fact that some of the patients 
received post -stenting chemotherapy and some didn't makes it quite difficult to assess the data 
presented.  Additionally, the fact that t he chemotherapy regimens were not the same for the 
group of patients receiving chemotherapy is also a problem.  LIkewise, the fact that different 
types of stents were used, is problematic.  Finally, the relatively short survival period following 
stenting ( 2.4 months) raises the question of whether or not this represents and effective therapy 
in these late stage patients.  
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
Unable to assess  
  
Are the conclusions drawn adequa tely supported by the data shown?  
If not, please explain in your comments to the authors.  
 
Yes 
 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended , please specify what aspects require further  
assessment in your comments to the editors.  
 
Not relevant to this manuscript  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
Declaration of competing in terests  
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1. Have you in the past five years received reimbursements, fees, funding, or salary from an  
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3. Do you hold or are you currently applying for any patents relating to the content of the  
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4. Have you received reimbursements, fees, funding, or salary from an organization that 
holds  or has applied for patents relating to the content of the manuscript?  
 
5. Do you have any other financial competing interests?  
 
6. Do you have any non -financial competing interests in relation to this paper?  
 
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below.  If your reply is y es to any, please give details below.  
 
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