Radiation Therapy Oncology Group

Dr. Chamora has recently been recruited as the inaugural chair of Breast Cancer Radiation Oncology at the University of Texas MD Anderson Cancer Center.

Believe it or not, I was there in 2013 at the RTOG headquarters as part of the RTOG Resident Training Fellowship when Dr. Chamora proposed the concept of BR002 almost 15 years ago.

Dr. Chamora, good to see you again and welcome to the NRG Oncology Podcast.

That was a super warm introduction.

I'm always listening to it as I drive my son to swim practice.

I just want to point out that it isn't just 2013.

It goes all the way back to 2007 is when I first proposed it, what was then RTOG and then became Energy Oncology.

And I remember then that everybody thought it was kind of crazy.

So mastectomy, or you can do breast conservation, which is lumpectomy with potentially radiation.

Radiation can be omitted in low-risk DCIS per the RTOG 9804 criteria.

which are those with grade one or two under 2.5 centimeters with margins over three millimeters.

And then for DCIS, you do want to have a negative margin of over two millimeters.

At 14 years, NRG Oncology's RTOG-0815 trial found that short-term hormone therapy with prostate radiation still cut metastases, yet it didn't significantly improve overall survival.

Now, Verisight and Arterra are competing to tell doctors which men can skip it.

And in the plenary, the NRG-GIO-03 trial of proton therapy for liver cancer crossed its futility boundary against standard photon radiation, in a disease where insurers already cover protons under conditions.

Our top story from Astro.

Men with intermediate-risk prostate cancer who get radiation are often given a few months of hormone therapy alongside it.

NRG Oncology's RTOG-0815 asked whether they still need it once the radiation dose has escalated.

It enrolled more than 1,500 men between 2009 and 2016, and Astro heard the long-term update.

Overall survival was the primary endpoint, and it wasn't significantly improved.

For men getting radiation for intermediate risk disease, the question is, who also needs short-course hormone therapy, or ADT? Verisight's Decipher, a tissue-based genomic risk test, is aimed at that question.

The data come from a retrospective analysis of archived tissue in the randomized RTOG-0815 trial, covering 395 of its 1,492 patients.

Verisight reports that men with intermediate or high scores had a 10-year distant metastasis rate 8 percentage points lower with ADT.

With low scores, the gap was 1 point and not significant.

And there is no doubt that the median overall survival in both arms seen in this trial seems to be substantially better than other studies of SVRT that we've seen in the past.

The comparison of this study to RTOG 1112 is dangerous, given that it was a very different patient population with many more patients with macrovascular invasion.

included on RTOG 1112.

But having said that, the survival is markedly better in this trial, and it is possible that some of that may be due to the advent of more effective systemic therapies that could be given at the time of progression.

Having said that, the progression-free survival was identical in both arms, and also both arms were substantially better than the progression-free survival seen in RTOG 1112.

With both arms

in NRGGI003 being well over a year, as opposed to the progression-free survival in RTOG1112 in the radiation arm being more along the lines of about nine months.

So I think that it is very possible that the outcomes could have been impacted by the impressive improvements in systemic therapy with immunotherapy-based regimens.

Yeah.

And we have evidence from RTOG 9811 that maybe pushes against cisplatin, right? Which is showing that potentially the outcomes weren't as good, although a very different design.

Yeah.

Where do you weigh in on this? Things about-

Yeah

... weekly cisplatin maybe?

Yeah, so RTOG, um, 9811, first just stepping back, looked at two cycles of, uh, induction cisplatin before proceeding to radiation.

Ultimately, at the initial analysis, there was no difference in DFS and OS, but on long-term evaluation, it does appear that mitomycin C was superior both for DFS and OS.