Review for 10.1186/s12876-017-0644-3 (2017)

Reviewer’s report  
 
Title:  The prevalence of gastric heterotopia of the proximal esophagus is underestimated , but 
preneoplasia is rare - correlation with Barrett's esophagus  
 
Version:  0 Date:  11 Feb 2017 
 
Reviewer:  Irene  Coati  
 
Reviewer’s report:  
 
The aim of this study is very interesting, but there are some imprecisions and advices in order to 
accept it.  
 
- An EGD was perfomed to 372 patients, but the text never explains the total number of patients 
with biopsies also. Particularly, the authors olny specify the number of "IP" biopsies (46), the 
number of gastric biopsies (277 ). They also write the number of patients with normal finding of 
upper gastrointestinal tract (201). I suggest the authors to add this information (total number of 
patients biopsied) in order to more precise.  
 
- I invite the authors to underline the discrep ancy between endoscopic and histologic results.  
 
The first sentence of "background" (line 69) gives the definition of IP, as a islands of gastric 
mucosa in the proximal esophagus. The gastric mucosa consists in a columnar epithelium, by 
definition. Conseque ntly, a definition of endoscopic IP presents many limits.  
 
In fact olny 40 out the 46 cases biopsied presented gastric mucosa. This aspect underlines the 
difficulty to give a real endoscopic diagnosis of IP. I invite the authors the explain a little bit 
more this aspect, expecially because they explain the difficulty to take biopsies from the 
proximal esophagus.  
 
 - In the "Discussion" the authors underline a prevalence of 14,5% of endoscopic IP. It could be 
interesting to add also the histologic prevalence o f IP, in order to give another information and to 
urdeline the differences between these 2 data.  
 
- At line 85, the authors could mention "Correa cascade" [J Dig Dis. 2012 Jan;13(1):2 -9. doi: 
10.1111/j.1751 -2980.2011.00550.x.  
 
The gastric precancerous cascad e.Correa P, Piazuelo MB.]  
 
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.  
 
Yes 
 
Are the conclusions drawn adequately 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 speci fy what aspects require further 
assessment in your comments to the editors.  
 
I am able to assess the statistics  
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
Declaration of competing interests  
Please complete a declaration of competing interests, considering the following questions:  
 
1. Have you in the past five years received reimbursements, fees, funding, or salary from an 
organisation that may in any way gain or lose financially from the publication of  this 
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2. Do you hold any stocks or shares in an organisation that may in any way gain or lose 
financially from the publication of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applyin g for any patents relating to the content of the 
manuscript?  
 
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?  
 
If you can answer no to all of the above, write 'I declare that I have no competing interests' 
below. If your reply is yes to any, please give details below . 
 
I declare that I have no competing interests.  
 
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