Review for 10.1186/s12876-020-01476-9 (2020)

Reviewer’ s report
Title: Comparison of prognostic impact of anatomic location of the pancreas on postoperative
pancreatic fistula in laparoscopic and open gastrectomy
Version: 0Date: 20 Aug 2020
Reviewer's report:
This retrospective study sought to compare the impact of anatomical location of the pancreas on
postoperative pancreatic fistula (POPF) in laparoscopic and open gastrectomy. Overall, this articlehad reasonable scientific rigour, however there are some flaws to be addressed. I recommend somerevisions to focus the goals of the paper, before it can be accepted.
General comments
1. As the authors noted in the results, there were some important difference in patients' background(age, disease stage, extent of lymph node dissection, etc) and they could affect the occurrence ofPOPF. Although advanced disease, total gastrectomy, D2 dissection can correlate with higherincidence of POPF, older age may have the opposite effect. Because surgeons may take intoconsideration the frailty due to old age when performing lymphadenectomy. In other words, D2 inolder patients and that in younger patients may differ. In general, propensity score matching(PSM) analysis should be considered in this situation. If it is not feasible to perform PSM due tothe lack of number of patients or events, the authors should discuss this as a limitation of the study.
2. Since biochemical pancreatic leak (BL in ISGPF) doesn't have clinical significance, grade B or
higher POPF probably should be defined as an event in this type of study. If it is not feasible dueto the lack of number of patients or events, the authors should also discuss this as a limitation of
the study.
Specific comments
1. Introduction, 2nd paragraph"JOCG" should be "JCOG".
2. Results, 2nd sub-section
The result of the area under the curve for the PLH should be interpreted. In general, a test with area0.5-0.7 indicated low accuracy.Akobeng AK. Understanding diagnostic tests 3: Receiver operating characteristic curves. ActaPaediatr. 2007 May;96(5):644-7. doi: 10.1111/j.1651-2227.2006.00178.x. Epub 2007 Mar 21.PMID: 17376185
3. Discussion, 3rd paragraph
As the authors mentioned, the left gastric artery is one of the landmarks for lymph node dissectionin gastrectomy. However, lymph nodes along the celiac artery behind the left gastric artery shouldalso be dissected in D1+ or D2 gastrectomy. In this sense the celiac artery may be more importantas the landmark and P-A length defined as the length between the pancreas and the root of the
celiac artery may be more strongly correlated with difficulty of lymphadenectomy and POPF.
4. Discussion, 2nd last paragraph
"Examining the anatomic pancreatic position in advanced gastric cancer patients who undergo LGis required as a next step" should be "Examining the correlation between the anatomic pancreaticposition and POPF in advanced gastric cancer patients who undergo LG is required as a next step".
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 registeredat Publons, they will notify you of the receipt of this review and update your profile as per yoursettings and their policy. If you are not registered with Publons, you will receive an email fromthem asking you to register in order for them to be able to recognize your review on your newprofile page. Publons may use the Review Data to generate derivative metadata for the benefit ofPublons and you as a reviewer, carefully considering the sensitivity of such information. Forexample, Publons may verify your record as a reviewer by updating your profile published on itswebservice 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
YesDeclaration 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.
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 manu-script is accepted for publication. Any comments that I do not wish to be included in the publishedreport have been included as confidential comments to the editor, which will not be published.Ifyou are not happy for us to publish this report, please contact the editorial office before completingthe review.If you wish, you can include your name in your published report. Please note you mustdecide 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?
YesAre the methods sufficiently described to allow the study to be repeated?YesIs the use of statistics and treatment of uncertainties appropriate?Yes
Is the presentation of the work clear?
YesAre the images in this manuscript (including electrophoretic gels and blots) free from apparent
manipulation?
Yes