You're correct.Clinicians in the real world are going to have...

You're correct.

Clinicians in the real world are going to have patients who are clearly unresectable/have metastases, and then the rest for whom either surgery is an option or there's advanced local disease but it looks unresectable for technical reasons expertly outlined by you..

I suspect that, again in the real world, anything that makes the surgeons deal with a smaller tumour (even if it was clearly resectable) is going to be used.

BR might have definitions for the purposes of research, but the definitions for standard pre-op use of chemo and RT/oncosil will be more flexible.

And as far as research goes, the comparators need to be clear. You're comparing (pre-surgery) C+RT (either oncosil or other) against chemo alone. Then maybe oncosil vs other forms of RT.

But there are ethical issues in witholding treatment options in a disease with so few options as pancreatic cancer.

I personally think the acceptable RCTs will be smaller than people imagine.