Review for 10.1186/s12876-020-01217-y (2020)

Revie wer’s report  
 
Title: Impact of preoperative fecal short chain fatty ac ids on postoperative infectious 
complication s in esophageal cancer patients  
 
Version: 0 Date: 28 Oct 2019  
 
Reviewer: Yoshihiro Nabeya  
 
Reviewer's report:  
Please send all comments for the authors from me in this box "without my name".  I do not wish 
any comments to be included in my named report, and I hope any comments will be published 
"without my name".   
 
This manuscript have reported the potential usefulness to modulate the intestinal environment 
and maintain concentrations of fecal organic acids before esophagectomy fot cancer.   
Although this manuscript may have useful information, I have raised some imp ortant issues that 
must be addressed before this manuscript will be acceptable for publication in BMC 
Gastroenterology.  
 
Major critique:  
(1) As the authors mentioned in the limitation of this study (P14 in the Discussion section), 
the heterogeneity of the condition among the subjects should be discussed more.  Do the authors 
have any data of intestinal environment before and after neoadjuvant therapy in patients who 
received it, in addition of postoperative period?  Otherwise, the authors should compare dat a of 
intestinal environment between patients who received neoadjuvant therapy and those who did 
not, at each time point of perioperative period, since they gave us only some information of 
patients who underwent neoadjuvant therapy (in the Discussion secti on) .  
(2) I agree the author's most important message that if a patient has low concentrations of 
SCFAs after receiving synbiotics, more careful attention should be paid during the perioperative 
period to prevent postoperative infectious complications. (P 14, Line 10 -12)  However, I would 
like the authors to mention the feasibility of determination of SCFAs concentrations including its 
cost in clinical practice.  How do the authors think about the possibility of clinical prevalence of 
this significant exami natiuon in the future?  
(3) In the first paragraph of the Discussion section, since the repetition of the results is too 
muchi, it should be a little more concise.  
 
Minor critique (Specific comments):  
(1) Some grammatical or typographical errors can be foun d in the text, and I wonder if all of 
the authors carefully checked the final version of the manuscript before submission.  The authors 
should ask a native English speaker for editing.  Please reconsider the issues I have raised as 
follows:  
① In Page 1 (ti tle page), Department of Gastroemterological Surgery"," (missing comma) is 
correct.  
② In Page 2, Line 12 -13, The sentence, "All patients were administered perioperative 
synbiotics." should be corrected to "Perioperative synbiotics were administered to all patients.". 
(grammaticall incorrect)  
③ In Page 2, line 14, The phrase, "with or without" should be replaced by "with and 
without".  
④ In Page 6, Line 1, The phrase, "This prospective study" may be better than "This study".  
⑤ In Page 6, Line 7, The phrase, " stomach, jejunum, or colon" may be replaced by 
"stomach or jejunum.". (No patient received reconstruction by colon conduit.)  
⑥ In Page 9, Line 8 -9, The phrase, "with or without" should be replaced by "with and 
without".  
⑦ In Page 14, Line 6 -7, The sentence s, "It is considered that different patients had different 
responses to synbiotics.  The mechanism of ・・・ ." may be replaced by "While the responses to 
synbiotics may depend on the patients' condition, the mechanism of ・・・ .". 
⑧ In Page 14, Line 10,"Therefore, " may be added at the beginning of the sentence, "If a 
patient has low ・・・ .". 
 
 
Are the met hods 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 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 manus cript or would you recommend an 
additional statistical review?  
If an additional s tatistical 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:  
 
Needs some language corrections before being published  
 
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 sal ary from an 
organisation that may in any way gain or lose financially from the publication of this  
manuscript, either now or in the future?  
 
2. Do you hold any stocks or shares in an organisation t hat may in any way gain or lose 
financially from the publica tion of this manuscript, either now or in the future?  
 
3. Do you hold or are you currently applying 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 dec lare 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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which I do not wish to be included in my named report can be in cluded as confidential comments 
to the editor s, which will not be published.  
 
I agree to the open peer review policy of the journal