Review for 10.1186/s12876-021-01700-0 (2021)

Reviewer’s report
Title: 
Clinical outcomes of early gastric cardiac cancer treated with endoscopic
submucosal dissection in patients with different indications
Version: 
1 
Date: 
14 Jun 2020
Reviewer's report:
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Thank you for giving me an opportunity to review this interesting paper. Authors
presented well about the clinical data of the EGCC patients who underwent ESD
in different indications. However, there are some major problems in this
manuscript to publish from this journal. Please perform the major revision about
my comments.
(1) At first, in this paper authors should mention the reason why early gastric
cancers located at cardia were examined. For example, the deference of
prognosis between cardiac carcinomas and another located carcinoma. 
(2) In my opinion, it is very uncertain generally what authors want to discuss and
conclude. Beyond the expanded indication (BEI) groups should be recommended
additional surgery strongly. In author's institution, I think that it has too few
additional operation examples.
(3) eCura system could be very useful and effective soring program, but the
object may think like an elderly patient and a patient having serious
complications. In this evaluation, eCura system was adapted and was parsed to
all patients. How about this opinion?
Are the methods appropriate and well described?
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Yes
Does the work include the necessary controls?
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authors.
Yes
Are the conclusions drawn adequately supported by the data shown?
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No
Are you able to assess any statistics in the manuscript or would you
recommend an additional statistical review?
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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
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