Review for 10.1186/s12876-020-01348-2 (2020)

Reviewer ’s report  
 
Title: The NETest Liquid Biopsy is Diagnostic for Gastric Neur oendocrine Tumors: 
Observations on the Blood -Based Identification of Microscopic and Macroscopic Residual 
Disease  
 
Version: 0 Date: 27 Nov 2019  
 
Reviewer: Edith Lahner  
 
Reviewer's report:  
 
I read with interest the paper on the NETest liquid biopsy and its diagnostic utility gastric 
neuroendocrine tumors. The topic of the paper seems to be interesting to  the readers of the 
journal. It is well written and readable. The abstract is more difficult to read for the number of 
abbreviations.  
 
Methods are clearly explained. Unfortunately, controls had no additional blood tests to rule out 
disease (CBC, gastrin?) and this should be explained (at least in the discussion section as limit of 
the study, 13% of false positives). Also the included subtypes of GNETs were unbalanced, 
probably due to the low prevalence of the disease. The sample number of cases is relative low, 
sample calculation is provided in statistical section, albeit without reporting the basis on which 
these calculation were performed. STARD guidelines have not be considered.  
 
Results are described in detail. Considering the means ±SD (numerically and r eported in graphs) 
of the NETest, there are some cases falling below the threshold for positivity of 20. Is this 
compatible with sensitivity values of 100%?  
In the discussion section, study limits are lacking.  
 
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
 
Does the work include the nece ssary 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.  
 
Yes 
 
 
 
 
Are you able to assess any statistics in the manus cript or would you recommend an 
additional statistical review?  
If an additional statistical review is recommended, please speci fy what aspects require further 
assessment in your comments to the editors.  
 
I am able to assess the statis tics 
 
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, f ees, funding, or salary from an 
organisation that may in any way gain or lose financial ly from the publication of this 
manuscript, either now or in the future?  
2. Do you hold any s tocks or shares in an organisation t hat 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 compe ting 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  
 
I agree to the open peer review policy of the journal. I understan d that my name will be included 
on my report to the authors and, if the manuscript is accepted f or publication, my named report 
including  any attachments I upload will be posted on the website along with the authors' 
responses. 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/ ). I understand that any c omments 
which I do not wish to be included in my named report can be in cluded as confidential comments 
to the editors, which will not be published.  
 
I agree to the open peer review policy of the journal