Gadoxetic Acid-Based MRI for Decision-Making in Hepatocellular Carcinoma Employing Perfusion Criteria Only—A Post Hoc Analysis from the SORAMIC Trial Diagnostic Cohort
, Alberto Benito 4, Bernhard Gebauer 5, Roberto Iezzi 6, Christian Loewe 7, Musturay Karçaaltincaba 8, Maciej Pech 9, Christian Sengel 10, Otto van Delden 11, Vincent Vandecaveye 12, Christoph J. Zech 13 and Jens Ricke 1Round 1
Reviewer 1 Report
The paper describes a post-hoc analysis comparing dynamic contrast enhance MRI with CT for the detection of HCC. It is a clearly written article. I have no major comment for the authors. One minor comment concerns figure 1. In this flow diagram, scans excluded from the per-protocol are detailed, but amount of exclusions by subgroup are not mentioned (though they are provided in table 4). In my opinion, figure 1 would be more clear if the amounts of these subgroups are detailed.
Author Response
Reviewer 1
The paper describes a post-hoc analysis comparing dynamic contrast enhance MRI with CT for the detection of HCC. It is a clearly written article. I have no major comment for the authors. One minor comment concerns figure 1. In this flow diagram, scans excluded from the per-protocol are detailed, but amount of exclusions by subgroup are not mentioned (though they are provided in table 4). In my opinion, figure 1 would be more clear if the amounts of these subgroups are detailed.
Author reply: Thank you for this valuable input. Indeed, it makes sense to display more obvious/detailed information about the specific exclusion reasons per imaging modality and the readers in Figure 1. Please find an elaborated version of Figure 1 in the revised manuscript.
Reviewer 2 Report
Title: Gadoxetic acid-based MRI for decision-making in hepatocellular carcinoma employing perfusion criteria only – a post hoc analysis from the SORAMIC trial diagnostic cohort
It dealt with comparing the perfusion criteria (arterial enhancement and wash-out) between gadoxetic acid MRI and CT. Overall, it is well-written, and the study's conclusion is reasonable. However, I have some points to be addressed in the manuscript.
- The subject in this study did not much include early-stage HCC. (BCLC 0 and 1=19.3%). I think the issue would be addressed in the discussion or limitation section.
- The perfusion criteria only in the gadoxetic acid MRI are not used in the actual practice. I think you would better address why the result has clinical significance nevertheless.
Author Response
Reviewer 2
It dealt with comparing the perfusion criteria (arterial enhancement and wash-out) between gadoxetic acid MRI and CT. Overall, it is well-written, and the study's conclusion is reasonable. However, I have some points to be addressed in the manuscript.
- The subject in this study did not much include early-stage HCC. (BCLC 0 and 1=19.3%). I think the issue would be addressed in the discussion or limitation section.
Author reply: Yes, more advanced tumor stages are overrepresented in comparison to earlier tumor stages in our trial (due to the structure of the therapeutic study arms), which might be a source of bias. However, the higher rate of advanced tumor stages reflects real life in HCC diagnosis. We added this potential bias in the limitations section.
- The perfusion criteria only in the gadoxetic acid MRI are not used in the actual practice. I think you would better address why the result has clinical significance nevertheless.
Author reply: Thank you for this input which will help to make the main message of our study more clear. Yes, there is no use of contrast dynamics with gadoxetic acid only in clinical practice. However, the contrast dynamics (as part of a fully-fledged hepatobiliary liver MRI) with gadoxetic acid are under dispute, mainly because of proper depiction of wash-out in the venous phase/diluted information by early uptake of gadoxetic acid. This might impair the applicability of gadoxetic acid as a standard contrast medium for a full set liver MRI (including T2, DWI and HBP). Our study aims to analyze the accuracy of contrast dynamics with gadoxetic acid (with regard to accuracy of treatment decisions) in order to support the use of the contrast dynamics as a part of multiparametric liver MRI with gadoxetic acid. In the revised version we have added a sentence in the Introduction and Conclusions which should support understanding of the clinical significance of the study.
