Ectopic Recurrence of Skull Base Chordoma after Proton Therapy

Round 1

Reviewer 1 Report

The authors responded to all my comments. I do not have any additionnal comment.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

In my opinion the topic of this paper
is not new (and for this reason I rated low novelty) However, the merit of this work is to accurately detail
from a medical-surgical point of view, a phenomenon that probably depends on the biological properties
of chordoma cells.
In fact chordoma cells produce a high amount of viscous matrix
which probably promotes the adhesion of the
tumor cells to the surgical instruments.
In my opinion, a comment about this characteristic of 
chordoma and the ectopic recurrence must be add in the
discussion section.

I have no further suggestions for the authors.

 

Author Response

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Reviewer 2 Report

An interesting subject highlighting the way that chordomas are spread by surgery. It is difficult to work out the treatment policy used at these institutions but it appears that radiotherapy may be used once the surgeon has run out of ideas.

It is common not to cover all the surgical tracks back to the skin and especially if endoscopic surgery is used, the radiation oncologist may not know exactly what was done.

The high rate of local recurrence quoted in reference 5 suggests radiotherapy may have a role earlier in the course of the disease.

The comment that radiotherapy is usually given using particles may not be true in most of the world.

There were only 30 patients and it is not clear why only 62% had received radiotherapy and also whether they came from one institution or from all those represented by the author affiliations. If all at one place, there are many authors and perhaps they could have found more cases.

Why was salvage RT often done using a linac?

Nice illustrations.

 

Author Response

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Reviewer 3 Report

I have no comments.

Authors shoud be congratulated for an excellent case-based analysis and  unique observations. All aspects of the  interpretation of their findings have been taken into account. 

Author Response

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Reviewer 4 Report

Thank you for giving me the opportunity to review this article which presents a series of cases of chordomas, some of which presented an ectopic recurrence.
The number of cases presented is very small. Even if it is a rare tumor, it is very difficult to draw conclusions because of the small size of the series presented. 
The authors present as ectopic recurrence the recurrences on the operative path, which is an unusual definition.
The question asked is not clear and the presentation of the results is more like a presentation of several cases.

Author Response

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