Topic: Drs. Abou-Alfa and O'Reilly's book

It has been very helpful to read the book 1000 Q &As about Biliary Cancer that is recommended by the Foundation. I have a question about Question 62 on page 72, if anyone has that book available. It has to do with how to know if the tumor is shrinking or increasing. It make is sound that it is hard to measure changes on the scans and therefore be cautious. Here is the quote from the book:

"For technical reasons the category of stable disease is applied to a result showing 30% shrinkage of the tumor up to a 20% increase in its size, accomodating for the technical limitations and other factors using radiological tests. It is important to factor  these considerations in when you review your CT
or MRI with your medical team."

Therefore maybe -in some cases- if the tumor has not increased by 20% we can't be sure the tumor has REALLY increased in size at all.

I would be interested in other people's thoughts especially from Dr. Abou-Alfa.
Thank you.

Re: Drs. Abou-Alfa and O'Reilly's book

jetcm....this is what I have learned: 
In re: to the technical limitations: the CT plate in itself measures 1cm hence, anything beneath is not visible on the scan.  Based on tumor size, this could encompass the percentages at question. 
Interpretation of MRI is difficult as well, as changes can be difficult to determine precisely. It is for that reason that the expertise of the physician is of most importance. 
I will reach out to Dr. Abou-Alfa for further explanation and post his response as well.
Hugs,
Marion

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