Reviewer’s report
Title: 
Severe weight loss after minimally invasive oesophagectomy is associated
with poor 5-year survival in patients with oesophageal cancer
Version: 
2 
Date: 
29 Jul 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?
No - there are minor issues
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?
Not sure - I am not able to assess the statistics in this study
INTERPRETATION - Is the current interpretation/discussion of the results
reasonable and not overstated?
No - there are minor issues
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?
Probably - with minor revisions
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?
It is improved by the revisions, but some issues remain.
REQUESTED REVISIONS: 
Design 
- minor issues. 
These have now been addressed in the limitations section
of the manuscript (Discussion).
Interpretation 
- minor issues
These relate to some revisions in the Discussion. 
Further revision of this section
would provide additional clarity about further research.
ADDITIONAL REQUESTS/SUGGESTIONS: 
There is still some uncertainty in that the authors state that "FT was likely placed
in patients with deep tumour invasion who underwent preoperative therapy.". 
If
the reasons for FT placement are not fully understood, this should be explored in
the Discussion and proposed as future research question to determine the effects
of FT placement on weight loss and survival. 
'Categorised' could be used in the text in some places in addition to 
'organised',
to improve the readability of the manuscript.
This section in the Discussion is new, and improves this section, however soe
further clarity is needed. 
"Previous studies reported that 10% weight loss was
associated with poor prognosis after
oesophagectomy ………………….no-FT group would be
needed."
Major - now that the cut-off for severe weight loss if clearer I am concerned that
in fact all of the patient in this study had severe weight loss post opertaively.
Most studies would categorise 10% weight loss as sever, so I think this may be a
reason why the patients in 
this study did quite badly - they were ALL severely
underweight. 
I cannot see an explanation for using this cut off, please provide it.
Because all the patients had severe weight loss, it would be more difficult to see
a difference between the FT and non FT groups. 
This might be an issue for
discussion.
Could I suggest: 
In this study, 60% of the patients experienced >10% weight loss. No
significant differences were found between these two groups. - This sentence
needs further discussion 
- this is a different finding from previous research and
no explanations are offered in the paper.
For the FT group, (median duration of FT placement 78
days) we *did* not demonstrate improvement of postoperative weight loss,
although some studies report that FT can improve nutritional status (how long
were these FT placed?).
It may be that nutritional support via FT might be needed for a longer time after
oesophagectomy. In our study, in the no FT group, we did not give nutritional
support. This might suggest that non FT patients should take an oral nutritional
supplement. Our results suggest that nutritional support for the FT group and no-
FT group would be needed. to reduce post-operative weight loss and improve
outcomes.
The paragraph which follows this would benefit from some minor revision as
there is some repetition."
Publons Reviewer Recognition
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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,
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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 
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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?
No
Are the methods sufficiently described to allow the study to be repeated?
No
Is the use of statistics and treatment of uncertainties appropriate?
No
Is the presentation of the work clear?
No
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
No
Reviewer’s report
Title: 
Severe weight loss after minimally invasive oesophagectomy is associated
with poor 5-year survival in patients with oesophageal cancer
Version: 
2 
Date: 
29 Jul 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?
No - there are minor issues
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?
Not sure - I am not able to assess the statistics in this study
INTERPRETATION - Is the current interpretation/discussion of the results
reasonable and not overstated?
No - there are minor issues
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?
Probably - with minor revisions
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?
It is improved by the revisions, but some issues remain.
REQUESTED REVISIONS: 
Design 
- minor issues. 
These have now been addressed in the limitations section
of the manuscript (Discussion).
Interpretation 
- minor issues
These relate to some revisions in the Discussion. 
Further revision of this section
would provide additional clarity about further research.
ADDITIONAL REQUESTS/SUGGESTIONS: 
There is still some uncertainty in that the authors state that "FT was likely placed
in patients with deep tumour invasion who underwent preoperative therapy.". 
If
the reasons for FT placement are not fully understood, this should be explored in
the Discussion and proposed as future research question to determine the effects
of FT placement on weight loss and survival. 
'Categorised' could be used in the text in some places in addition to 
'organised',
to improve the readability of the manuscript.
This section in the Discussion is new, and improves this section, however soe
further clarity is needed. 
"Previous studies reported that 10% weight loss was
associated with poor prognosis after
oesophagectomy ………………….no-FT group would be
needed."
Major - now that the cut-off for severe weight loss if clearer I am concerned that
in fact all of the patient in this study had severe weight loss post opertaively.
Most studies would categorise 10% weight loss as sever, so I think this may be a
reason why the patients in 
this study did quite badly - they were ALL severely
underweight. 
I cannot see an explanation for using this cut off, please provide it.
Because all the patients had severe weight loss, it would be more difficult to see
a difference between the FT and non FT groups. 
This might be an issue for
discussion.
Could I suggest: 
In this study, 60% of the patients experienced >10% weight loss. No
significant differences were found between these two groups. - This sentence
needs further discussion 
- this is a different finding from previous research and
no explanations are offered in the paper.
For the FT group, (median duration of FT placement 78
days) we *did* not demonstrate improvement of postoperative weight loss,
although some studies report that FT can improve nutritional status (how long
were these FT placed?).
It may be that nutritional support via FT might be needed for a longer time after
oesophagectomy. In our study, in the no FT group, we did not give nutritional
support. This might suggest that non FT patients should take an oral nutritional
supplement. Our results suggest that nutritional support for the FT group and no-
FT group would be needed. to reduce post-operative weight loss and improve
outcomes.
The paragraph which follows this would benefit from some minor revision as
there is some repetition."
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?
No
Are the methods sufficiently described to allow the study to be repeated?
No
Is the use of statistics and treatment of uncertainties appropriate?
No
Is the presentation of the work clear?
No
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
No
Please review this paper.
user
Reviewer’s report
Title: 
Severe weight loss after minimally invasive oesophagectomy is associated
with poor 5-year survival in patients with oesophageal cancer
Version: 
2 
Date: 
29 Jul 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?
No - there are minor issues
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?
Not sure - I am not able to assess the statistics in this study
INTERPRETATION - Is the current interpretation/discussion of the results
reasonable and not overstated?
No - there are minor issues
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?
Probably - with minor revisions
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?
It is improved by the revisions, but some issues remain.
REQUESTED REVISIONS: 
Design 
- minor issues. 
These have now been addressed in the limitations section
of the manuscript (Discussion).
Interpretation 
- minor issues
These relate to some revisions in the Discussion. 
Further revision of this section
would provide additional clarity about further research.
ADDITIONAL REQUESTS/SUGGESTIONS: 
There is still some uncertainty in that the authors state that "FT was likely placed
in patients with deep tumour invasion who underwent preoperative therapy.". 
If
the reasons for FT placement are not fully understood, this should be explored in
the Discussion and proposed as future research question to determine the effects
of FT placement on weight loss and survival. 
'Categorised' could be used in the text in some places in addition to 
'organised',
to improve the readability of the manuscript.
This section in the Discussion is new, and improves this section, however soe
further clarity is needed. 
"Previous studies reported that 10% weight loss was
associated with poor prognosis after
oesophagectomy ………………….no-FT group would be
needed."
Major - now that the cut-off for severe weight loss if clearer I am concerned that
in fact all of the patient in this study had severe weight loss post opertaively.
Most studies would categorise 10% weight loss as sever, so I think this may be a
reason why the patients in 
this study did quite badly - they were ALL severely
underweight. 
I cannot see an explanation for using this cut off, please provide it.
Because all the patients had severe weight loss, it would be more difficult to see
a difference between the FT and non FT groups. 
This might be an issue for
discussion.
Could I suggest: 
In this study, 60% of the patients experienced >10% weight loss. No
significant differences were found between these two groups. - This sentence
needs further discussion 
- this is a different finding from previous research and
no explanations are offered in the paper.
For the FT group, (median duration of FT placement 78
days) we *did* not demonstrate improvement of postoperative weight loss,
although some studies report that FT can improve nutritional status (how long
were these FT placed?).
It may be that nutritional support via FT might be needed for a longer time after
oesophagectomy. In our study, in the no FT group, we did not give nutritional
support. This might suggest that non FT patients should take an oral nutritional
supplement. Our results suggest that nutritional support for the FT group and no-
FT group would be needed. to reduce post-operative weight loss and improve
outcomes.
The paragraph which follows this would benefit from some minor revision as
there is some repetition."
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?
No
Are the methods sufficiently described to allow the study to be repeated?
No
Is the use of statistics and treatment of uncertainties appropriate?
No
Is the presentation of the work clear?
No
Are the images in this manuscript (including electrophoretic gels and blots) free
from apparent manipulation?
No
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