Review for 10.1186/s12876-018-0846-3 (2018)

Reviewer’s report
Title: Male sex and history of ischemic heart disease are major risk factors for anastomotic leakage  
after laparoscopic anterior resection in patients with rectal cancer
Version: 1 Date: 01 Jun 2018
Reviewer: ORHAN ALIMOGLU
Reviewer's report:
In this study, the authors aimed to investigate the risk factors of anastomotic leakage after laparoscopic  
rectal cancer surgery. Male gender and ischemic heart disease were determined to be the identified risk  
factors. 
In the Abstract, it was stated that "Reconsidering surgical procedures including the creation of a  
diverting ileostomy or avoiding anastomosis will help reduce the frequency of anastomotic leakage  
among patients with this background". It has been considered that this comment is not correct and this  
interpretation should not be included in the article.
The Background section consists of two paragraphs which are inadequate, and contains insufficient  
information.
In the Methods section; explanations for the reasons of conversion and the detailed numbers of patients  
having undergone conversions according to these reasons constitute unnecessary information and may  
be deleted. The use of transanal drains are controversial in colorectal surgery and the routine removal  
of these drains on the 4th-6th postoperative days seems to lead to an elongated drain time which may  
have unfavorable consequences as encountered in this study population as well. Additionally, it would  
be more appropriate if the  authors  provided  more  detailed information about the features  of the  
anastomotic leaks, particularly after laparoscopic surgery.
There are too many tables in the manuscript, and it is necessary to reduce the number of tables. 
In the Results section; all data written in the text as the results of the study is given in the Tables as  
well. The authors should give the results either in the Tables, or in the text. This may also help to  
reduce either the word count in the text, or may give the opportunity to reduce the number of tables  
since The study is retrospective and although having investigated a total 154 "consecutive" patients, the  
authors have reduced the study group to 100 patients comprising of only male rectal cancer patients  
which spoils the homogeneity of the study group leading to an impression of a possible bias at first  
sight. There are inconsistencies in concern of the numeric values of the results of certain parameters  
such as anastomotic leakage and temporary stoma creation.  
There are too many repetations including repeated information both in the Discussion section and  
throughout the entire text. Since the use of transanal drains is controversial, the discussion about this  
issue is unnecessary and conflicting. The authors focused on parameters including ischemic heart  
disease, renal failure and male gender in the discussion according to the results of their study. However,  
other important factors leading to anastomotic leakage should also be thoroughly discussed in light of  
the literature.   
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
No
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.
No
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  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 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 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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