Review for 10.1186/s12876-018-0912-x (2018)

Reviewer ’s report  
 
Title: Characterization of intrahepatic cholangiocarcinoma after curative resection: outcome, 
prognostic factor, and recurrence  
 
Version: 0 Date: 11 Sep 2018  
 
Reviewer: Dirk Stippel  
 
Reviewer's report:  
 
The manuscrip t is a retrospective report on a single center series of R0 resections of intrahepatic 
cholangiocarcinoma. A strength of the study is the large number of patients resected (n=216) for 
a rather seldom entity. A weakness is the long period of 37 years of pat ient inclusion. The overall 
results are good and compare favorably with published data. A unique and original aspect is the 
survival of patients resected for local intrahepatic recurrence. The manuscript does not include 
other novel parameters. It rather r eports on the state of art that can be achieved nowadays by 
resection.  
 
Attention to the following suggestions might improve the paper:  
1) Even if the principle mode of therapy did not change during the 37 years, there were a lot of 
changes in surgical tech nique, intensive care medicine and other factors that are difficult to 
define precisely. Therefore the multivariate analysis should include a time period variable as 
a potential independent factor.  
2a) The TNM is different concerning the T stage for the Japanese and the UICC/AJCC system, 
which one was used?  
2b) UICC TNM staging did change during the time period, where all histologies reevaluated for 
a common revision of the staging system?  
3) The ana lysis showed that intrahepatic recurrence only showed a better survival than any other 
recurrence pattern. Did any of your prognostic factors predict intrahepatic only recurrence?  
4) Did any patient receive adjuvant chemotherapy, and if yes was there an in fluence on survival?  
5) Die any of the patient with recurrence receive palliative chemotherapy, and if yes was there 
any influence on survival?  
Are the methods appropriate and well described?  
If not, please specify what is required in your comments to the authors.  
 
Yes 
Does the work inc lude the necessary 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 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.  
 
I am able to ass ess the statistics  
 
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, 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 recei ved 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.  
 
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on my report to the authors and, if the manuscript is accepted for publication, my named report  
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