Thread by @cancerphysicist

Today is International Clinical Trials Day! #CTD2019

In the spirit of #CTD2019, I thought I’d take a bit of time to talk about medical physicists and radiotherapy trials #medphys #radonc
@ipemnews @EFOMP_org @aapmHQ

Why should radiotherapy trialists care about medical physicists? And why should physicists involve themselves in trials?

The short answer: It makes trials a whole lot better!

The slightly longer answer: It ensures maximum value from data that we are entrusted by patients

And the properly detailed answer will take a couple of tweetorials ☺️

Most people will probably think of physicists on clinical trials as something like this

Or from the annoying "sorry, no, your centre cannot open for recruitment until you have passed you dosimetry audit" or "that patient need prospective outlining review before planning can start" ...

... but there is a reason that we keep nagging you about this

Trials patients treated with major radiotherapy protocol violations (e.g. outlining or planning) do worse than other patients on the same trial, independent of other risk factors. But the risk can be mitigated by prospective review and feedback
ncbi.nlm.nih.gov/pubmed/20479390

The Peters et al paper is well known. By now, this effect has been shown enough times that we have at least two systematic reviews ncbi.nlm.nih.gov/pubmed/23468460
ncbi.nlm.nih.gov/pubmed/22985777

But we need good quality radiotherapy on trials not just for the sake of the individual trial patients!

Bad radiotherapy may introduce heterogeneity in outcomes, diluting a treatment effect - and ultimately risking your trial
ncbi.nlm.nih.gov/pubmed/17727987

But just as important, radiotherapy QA groups have turned out to be pretty nifty at picking up on more general problems with radiotherapy delivery - (hopefully) improving radiotherapy for all patients, not just on trial
ncbi.nlm.nih.gov/pubmed/28721904

So trial audits and QA are vitally important!

Luckily, we have gotten pretty good at it by now. And there are global efforts to standardize our trial QA internationally rtqaharmonization.org

This is Helen. She's coordinating all of our radiotherapy QA here in Leeds @OncologyLeedsTH, and works with @RTTQA_UK

She also trials baking with new and unusual flavours each year for #CTD2019, which is obviously why we like her so much 😁

To ensure that Helen continues to bring us cakes, please, please involve your friendly neighborhood trial physicist in protocol writing, radiotherapy guideline creation and site setup right from day one!

There is so much more that physicists can bring to radiotherapy trials, however, in addition to trial QA.

To follow later today: Why physicists are ideally placed to enhance the value of trials - trial design, sub-studies, secondary analyses, and more!
#medphys #radonc

Link to part II

https://twitter.com/cancerphysicist/status/1130445680554774530