Review for 10.1186/s12876-020-01543-1 (2020)

Reviewer’s report
Title: 
Severe weight loss after minimally invasive oesophagectomy is associated
with poor 5-year survival in patients with oesophageal cancer
Version: 
4 
Date: 
29 Oct 2020
Reviewer's report:
PEER REVIEWER ASSESSMENTS: 
OBJECTIVE - Full research articles: is there a clear objective that addresses one
or several testable research questions? (Brief or other article types: is there a
clear objective?)
Yes - there is a clear objective
DESIGN - Is the current approach (including controls and analysis protocols)
appropriate for the objective?
Yes - the approach is appropriate
EXECUTION - Are the experiments and analyses performed with sufficient
technical rigor to allow confidence in the results?
Yes - experiments and analyses were performed appropriately
STATISTICS - Is the use of statistics in the manuscript appropriate?
Yes - appropriate statistical analyses have been used in the study
INTERPRETATION - Is the current interpretation/discussion of the results
reasonable and not overstated?
Yes - the author's interpretation is reasonable
OVERALL MANUSCRIPT POTENTIAL - Has the author addressed your
concerns sufficiently for you to now recommend the work as a technically sound
contribution? If not, can further revisions be made to make the work technically
sound?
Yes - current version is technically sound
PEER REVIEWER COMMENTS: 
GENERAL COMMENTS: * Have the authors responded adequately to each of
the questions or concerns you raised in your comments?
YES
* Have they also made changes to reflect their responses in the manuscript
itself?
YES
* What is your overall impression of the revised manuscript?
Suitable for publication at the editor's discretion.
REQUESTED REVISIONS: 
No major edits required.
Thank you for making these revisions. 
I think the changes to the text
(Discussion) in response to my comments about all the patients having severe
weight loss is good. 
It provides much needed clarification about the rationale
behind the authors' choice of a 10% cut of for weight loss. The referencing for
this change is appropriate (D'Journo; WHO. 
(Page 11 lines 11-16.))
Thank you also for discussing whether the patients being severely underweight
may have led to an inability to see statistically significantly differences between
the FT and non FT groups in terms of OS and weight loss.
The addition to the Discussion (page 12, line 10-15) is good. 
It is now clear that
enteral nutrition can still lead to poor prognosis and nutritional deficiencies after
oesophagectomy need improved oral intake 
- 
further research might help to
clarify this. 
The changes to the text strengthen the conclusions of the paper.
Re my final point " Is it possible that patients with higher body mass at surgery
do better if they have a FT placed and are given enteral nutrition?" The sentence
added to the discussion (page 13, line 19-23) is helpful, although it could be
made clearer that we do not know at present if having a higher body mass index
before surgery confers an advantage to the patient. 
This issue could be examined
in further research, however no changes to the manuscript are required to address
this.
The changes to the manuscript are adequate.
Page 7 line 15 type: 
*The 16 patients were categorized into a severe weight loss
group (n = 65) (more than 10% weight loss) and 
a moderate weight loss group
(less than 10% weight loss) (n = 252).
There may be other typographical and grammatical errors and I suggest a
thorough proofread before publication please.
* What is your overall impression of the revised manuscript?
Suitable for publication subject to the editor's discretion. 
I thank the authors for
their detailed attention and response to my comments. 
Thank you for the
opportunity to review this paper.
Publons Reviewer Recognition
. Springer Nature can send verification of this
review directly to Publons (a subsidiary of Clarivate Analytics). If you would
like to take advantage of this service, please click on the “Yes” option below.
Your name, email address, title of the reviewed manuscript, name of the journal,
and date of your review submission (the “Review Data”) will then be transmitted
to Publons upon publication of the manuscript. If you have already registered at
Publons, they will notify you of the receipt of this review and update your profile
as per your settings and their policy. If you are not registered with Publons, you
will receive an email from them asking you to register in order for them to be
able to recognize your review on your new profile page. Publons may use the
Review Data to generate derivative metadata for the benefit of Publons and you
as a reviewer, carefully considering the sensitivity of such information. For
example, Publons may verify your record as a reviewer by updating your profile
published on its webservice if you have registered for such service or help
editors to identify candidate reviewers. Please find the details of processing in
Publons’ privacy policy 
https://publons.com/about/terms
No
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.
This reviewer has been recruited by a partner organization, Research Square.
Reviewers with declared or apparent competing interests are not utilized for
these reviews. This reviewer has agreed to publication of their comments online
under a Creative Commons Attribution License attributed to Research Square
and was paid a small honorarium for completing the review within a specified
timeframe. Honoraria for reviews such as this are paid regardless of the reviewer
recommendation.
Reviewer Publication Consent.
 I agree for my report to be made available
under an Open Access Creative Commons CC-BY License (
http://creativecommons.org/licenses/by/4.0
) if this manuscript is accepted for
publication. Any comments that I do not wish to be included in the published
report have been included as confidential comments to the editor, which will not
be published.
If you are not happy for us to publish this report, please contact the editorial
office before completing the review.
If you wish, you can include your name in your published report. Please note
you must decide whether to include your name at the start of the process and
confirm this decision whenever prompted. If you change your decision later, we
will not be able to publish your name.
I agree to the terms of the CC-BY 4.0 license; please 
do not
 publish my name
with my report. (default)
Is the study design appropriate to answer the research question (including the use
of appropriate controls), and are the conclusions supported by the evidence
presented?
Yes
Are the methods sufficiently described to allow the study to be repeated?
Yes
Is the use of statistics and treatment of uncertainties appropriate?
Yes
Is the presentation of the work clear?
No
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
Yes