Anyone participating in the Dapper Clinical Trial?

For anyone learning more about this trial being conducted at Mayo Clinic in Rochester, here's more information.
- Daily Adaptive Post-Prostatectomy With Stereotactic Ablative Radiotherapy in Patients With Prostate Cancer (DAPPER) https://classic.clinicaltrials.gov/ct2/show/NCT05830838

Quote from the description "Adaptive radiotherapy is an emerging treatment technique that uses daily imaging to adjust treatment volumes, ensure accurate dose delivery, and allow the use of smaller planning target volume margins."
That just seem to make sense doesn't it?

@rgnmayo, I'm glad that this trial option is available to you. You're asking good questions and I hope others here who are enrolled in the study will chime in. In the meantime, would you mind sharing a bit more about your decision factors. Did the study team share how the treatment differs from standard treatment? And how side effects may be different?

In my case the standard treatment is Intensity modulated photon radiotherapy (IMRT) 70 Gy over 35 single fractions to the prostate bed and +/- pelvic lymph nodes daily Monday through Friday. Treatments would be completed in about 7 months.

Treatment under the DAPPER Clinical Study consist of Ultra-hypofractionated daily adaptive salvage stereotactic ablative radiotherapy (SABR) 5 single fractions (every other weekday) with daily pretreatment imaging and re planning to the prostate fossa +/- treatment of pelvic lymph nodes, at treating physician's discretion. Treatments would be completed in about 2 weeks.

The appeal of the DAPPER treatment is the daily pretreatment imaging and re planning that will hopefully help target the radiation reduce the side effects of radiation on adjacent organs and the shorter treatment period (2 weeks versus 7 months). One drawback to the DAPPER treatment is that I would have to travel to Rochester for the pretreatment planning and treatments and follow up appointments.

For RT, both as primary tx and salvage tx, there is a clear patient and provider interest in fewer number of total txs.
However, the total radiation dose appears to be the same; less sessions; higher dose per session.
I received Salvage Radiation 37 txs of IMRT for a total dose of 66.6 gy to the entire prostate bed (45 gy to the lymph nodes); 1.8 gy per session. Daily for almost 8 wks.
Of course a shorter treatment course (measured in time/number of txs) would have been appealing.
My concern would be the higher radiation doses per tx, if the goal remains a total of 70 gy in your case, or 66.6 in my case.
I could pontificate/speculate additionally (without sound basis) about patient, provider and insurer interests, but maybe retired Radiologist has a more educated and nuanced thought on this.
Anyway, I cannot discern any residual side effects from my salvage radiation treatments, now 12 months ago. And unless there is a PCa tx therapeutic benefit, the lower daily dose of radiation over a longer period of time sounds "safer" (as if I have any idea of what is "safer" regarding radiation).
Enough from me.
We, and I believe our providers, are all hoping for the safest and most effective treatments.
Best to all.

Michael,
My local radiologist is recommending salvage radiation to the prostate bed only without ADT, 66.6 Gy over 37 fractions which is similar to your treatment. You say no residual side effects. Any side effects during or shortly after treatments? What do you mean by "PCa tx therapeutic benefit?"
Thanks for your posting.
Ralph

Colleen,
I am trying to reach out to patients that have participated in the DAPPER clinical trial for treatment of prostate cancer (to learn from their experience).
Do you have any suggestions on how to connect with DAPPER patients?
Ralph

I was trying to express my concern about receiving higher doses of radiation each treatment over a shorter period of time. That may have been attractive to me if there was a treatment benefit to the higher exposure; in other words, if it worked better to eradicate my residual cancer. Theoretical Q because I did not have a choice and my treatment is completed.

Otherwise, I would have been concerned about the delivery of higher doses of radiation each treatment, even if the total dosage added up to the same 66.6 gy. If that makes sense.

As for radiation side effects (SEs), I did not feel that I had any the first month. The 2d month I had bowel issues (more frequent movements and diarrhea) and rectal irritation. All resolved w/in 2 - 3 weeks of completion of radiation.

My additional layperson input is to have a further discussion about ADT.

ADT SEs suck. Some men have more or less SEs, and mine probably were moderate. Still sucked.

And while I would have loved to avoid ADT altogether, my Radiation Oncologist at Johns Hopkins strongly recommended a short term of ADT, which he told me improved results by 20 % (and the SPPORT trial supports whole prostate bed radiation [WPRT] together with 4 - 6 mos of ADT).

I was prescribed a 4 month course of ADT, and I chose Orgovyx, and think that it was a good medication choice for me. I probably would have gone with 6 mos if "pushed" a bit.

My 2 friends received similar salvage radiation treatment from 2 different Rad Oncs at Johns Hopkins, but they each were prescribed 6 mos of ADT together with the radiation. One took Eligard and the other Orgovyx. Again, I do a worry if I was 2 months short in my ADT.

And that brings us back to the "Gerbil Wheel" conundrum of trying to decide or agree to the varying treatment recommendations for PCa.

I chose a Center of Excellence, decided that I trusted my Rad Onc and institution and followed his recommendations. Does not mean that I do not question, well, everything. I call it residual worry. Maybe that should be added as a SE to all PCa treatments. But now I digress substantially.

I hope that some (any) of this missive has been worthy of your consideration.

Best to all.

I am. 5 sbrt treatments and a 4 month Lupron shot. Psa at time of radiation was .24. PSMA scan showed minor take up around area of vas deferens were. MRI showed no evidence of disease.
Radiation was a breeze. Std side effects from lupron.
3 month Psa undetectable. Follow up call with RO Thursday.
As of now I would recommend. I really liked the idea of reimagining and updating treatment plan at each treatment. That adds about 30 min so total treatment time was 45 min

Ping me. I am

rkurtzjr,

Where you treated under the DAPPER Clinical trial?

Ralph