Review for 10.1186/s12876-020-01221-2 (2020)

Reviewer’s report
Title: Human Herpesvirus 8-associated colonic Kaposi ’s sarcoma during vedolizumab treatment
in ulcerative colitis: a case report and review of the literature
Version: 1 Date: 30 Nov 2019
Reviewer: Motohiro Esaki
Reviewer's report:
Comments 
This manuscript demonstrated a case with UC who developed colonic Kaposi's sarcoma (KS) during
immunosuppressive  treatments  including  vedolizumab.  Although  iatrogenic  KS  is  known  as  an
epidemiologic-clinical type, it seems necessary to note that iatrogenic KS can develop even in patients
with inflammatory bowel disease under immunosuppressive treatments. 
Criticisms 
Although colonic KS developed under the treatment of vedolizumab (VDZ), the patient had been
treated with immunosuppressive agents other than VDZ for 5 years. Therefore, it might be better to
refrain the description that local immunosuppressive state by VDZ may have promoted the reactivation
of a latent HHV-8 infection endowed with oncogenic potentialities, as has been mentioned in the
conclusion. 
The patient underwent total colectomy and subsequent histological examination confirmed colonic KS.
The authors should describe precise location and extent of colonic KS by showing the scheme of the
resected specimens.  
Is it possible to show colonoscopic images of KS instead of Figure 1? If it's possible, the manuscript
could become much more informative for readers. 
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
Unable to assess
Does the work include the necessary controls?
If not, please specify which controls are required in your comments to the authors.
Unable to assess
Are the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
No
Are you able to assess any statistics in the manuscript or would you recommend an
additional statistical review?
If an additional statistical review is recommended, please specify what aspects require further
assessment in your comments to the editors.
Not relevant to this manuscript
Quality of written English
Please indicate the quality of language in the manuscript:
Acceptable
Declaration of competing interests
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