Review for 10.1186/s12876-017-0701-y (2017)

Reviewer ’s report  
 
Title:  Efficacy and safety of additional surgery after non -curative endoscopic submucosal 
dissection for early colorectal cancer  
 
Version: 0 Date: 26 Jul 2017 
 
Reviewer:  Mohamed  Othman  
 
Reviewer’s report:  
 
This is a retrospective study examining  the safety of additional surgery after non curative ESD. 
The rate of LNM was 9.8%. Lymphova scular invasion seen on ESD specimen was predictor of 
LNM. No recurrence was seen in the follow up period but complication rate was 6%.  
 
 
Major comments:  
 
The cohort does not include a control patients who underwent ESD alone without surgery. This 
compariso n could made  the study more valuable.  
 
 
Minor comments  
 
What are type of surgery performed  
 
Were any of the patients who had lymphovascular infiltration, had another reason for additional 
surgery such positive margin or deep T1 cancer?  
 
Discussion should be  expanded to include the utility of additional surgery with possible 
complication rate of 6% compared to the risk of LNM of 10% if no surgery is performed.  
 
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.  
 
No 
 
Are the con clusions 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 specify 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 o r 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 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 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 man uscript?  
 
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.  
 
No 
 
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to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal