QUESTIONAre these patients - who have been scanned with cancer...

QUESTION
Are these patients - who have been scanned with cancer found - not allowed any treatment until after the follow up SOC scan?
Otherwise, wouldn't it be possible for cu64 to have picked up a tumour that the SOC missed, receive some form of treatment that shrinks the tumour over a 6 months period, then be scanned again using the SOC which (due to the tumour shrinkage), again fails to identify it? We'd be back to a false positive, even though the tumour did exist ...

ANSWER
Here is the COBRA Trial Protocol CLP06 Prot_000.pdf, from which we can see that they are allowed treatment – its up to the treating doctor.

Here is a reconstructed extract of the Schedule of Assessments (Table 5)


KEY POINTS
Cu64 is experimental, so the expectation is that SOC drives treatment. They have SOC before getting onto the trial.
a) The protocol asks the treating Doctor to write a treatment plan based on SOC (before the patient has a Cu64 scan). Thats the Disease Management Form.
b) The patient then gets their Cu64 scan. This is interpreted LOCALLY (for local decisions), and also sent to Central processing by blinded reviewers. c) The LOCAL interpretation report is given to the treating doctor, who then completes version 2 of the Disease Management Form. Is the new knowledge gained enough to influence a change of treatment? 48% said YES!
d) The treating doctor then does whatever is relevant and appropriate.

So, the question of treatment potentially compromising the ability of SOC (making it fail to detect disease sooner than later) applies to those who actually got treated post Cu64 positive scan. But - not all were treated, since this is an experimental scan, and some doctors did not think there was a need to change their plans (they were adding nothing to the management they planned based on SOC alone). Maybe, they treated the patients - maybe they didn’t!