Should I insist on Whole Pelvic Radiation Therapy (WPRT)?

[Infamous9597]

Given my condition (see profile), should I ask for Whole Pelvic Radiation Therapy (WPRT)? Multiple doctors have said I don't need WPRT due to my low Decipher score, although it would give me better peace of mind. However, I am concerned about the additional side effects.

Here are my questions, and I hope you can provide some insights:

1) When comparing WPRT to PORT, how much more LONG-TERM toxicity does WPRT impose?

2) I read that SBRT can be used for whole pelvic radiation therapy (WPRT), but it is not as established as IMRT as a standard of care. Should I switch to 25 sessions of IMRT?

3) Do you think treating the whole pelvis would be excessive, considering I'm already on ADT?

[Mgtd]

I am no technical expert but I had radiation to the prostate and pelvic area. I had 25 radiation sessions and the amount of radiation to each area was different. Pelvic radiation was suggested by my radiation oncologist.

No real issues to speak of. I am almost 15 months out of radiation and have been off ADT 10 months. I had a 6 month course. One month prior and 5 months post.

In hindsight it gave me the best chance for a cure and hopefully not have a recurrence. Only time will really tell. My driving thought in my decision was to take the best chance for a cure.

Good luck with your decision not sure there is a perfect choice.

[tn12 in reply to Mgtd]

Please fill out your bio. Would be helpful. Thanks

[kiyo]

I don't know if this is helpful or not -----my husband is finishing up his last CyberKnife treatment on Friday and then will be going through 25 radiation sessions with IMRT as a prophylactic treatment. Although there are no lymph nodes involved, his RO highly recommded adding the latter because of my husband's high risk profile. Here is an article discussing the POP-RT clinical trial on whole pelvic radiation for high-risk and very high-risk prostate cancer patients: ascopubs.org/doi/10.1200/JC.... So I suspect it is all dependent on a person's risk factors.

[Infamous9597 in reply to kiyo]

just noticed your husband and I share similar profile. Best of wishes to your husband.

[kiyo in reply to Infamous9597]

Thank you! And best luck with your treatment as well!

[Tall_Allen]

Why do you imagine that WPRT would be beneficial for you? Based on your profile, that would be absurd.

[Infamous9597 in reply to Tall_Allen]

Based on the MRI interpretation from MSKCC, I am classified as stage 3Ta, which is considered high risk. I believe there is a high probability of microscopic lymph node metastases, even though the PSMA scan couldn't detect it.

Am I overthinking this? In your opinion, am I receiving the best course of treatment with Orgovyx for 6 months, 1 session of HDR brachytherapy, and 5 sessions of Truebeam SBRT (prostate-only)? Your help is greatly appreciated.

[Tall_Allen in reply to Infamous9597]

Got it! Thanks for explaining that. A lot depends on your staging -- was it focal or does there seem to be significant capsular penetration? MRIs aren't very precise, if it was only focal:

prostatecancer.news/2020/04...

The best data we have on WPRT comes from the POP-RT trial. They gave WPRT to GS7 men only if PSA>15:

prostatecancer.news/2021/08...

I know that MSK did a clinical trial combining BT and SBRT, but that seems unnecessarily duplicative to me - either is curative, and combining them only adds to toxicity and inconvenience.

[Infamous9597 in reply to Tall_Allen]

Thank you so much for the information. I just reviewed all three of my MRI reports more carefully, but couldn't find any mention of focal or significant capsular penetration. I have updated my profile to include excerpts from each report. Please feel free to review.

If I understand correctly, are you suggesting that I should consider BT combined with whole pelvic IMRT, since BT and SBRT are duplicative?

[Tall_Allen in reply to Infamous9597]

"gross EPE" means it was not focal, and loss of capsule, bulging and irregularity suggest it is not focal. It may even be stage T3b Seminal vesicle) or T4 (rectum, pubococcygeus muscle).

Yes, WPRT with BT boost to the prostate can get the prostate dose as high as you like. I am partial (with no evidence) to using MRI-targeted linacs in cases like yours because it can preserve the rectal wall and bowels.

[Infamous9597 in reply to Tall_Allen]

Ty TA.

Ironically, MSK refused to give me MR-Linac and instead offered TrueBeam SBRT. In that case, should I request a switch to whole pelvic IMRT with a BT boost?

Additionally, should I extend the duration of ADT? I was given 6 month of ADT due to low Decipher.

[Tall_Allen in reply to Infamous9597]

Your T3a puts you in the high-risk category. That requires 12 months of ADT with brachy boost therapy:

prostatecancer.news/2022/01...

IMO the WPRT and the possible T4 drives the need for an MR-linac. Maybe discuss this with Sean McBride?

[Infamous9597 in reply to Tall_Allen]

I have been seeing Dr. Marisa Kollmeier at MSK, and as I mentioned, she only offered TrueBeam SBRT, not MR-Linac. In that case, I would prefer to proceed with IMRT. Do you agree?

By the way, I have seen you recommend Dr. Sean McBride in other posts. However, are you familiar with Dr. Marisa Kollmeier?

[Tall_Allen in reply to Infamous9597]

I'm familiar with her by reputation. She was mentored in brachytherapy by Michael Zelefsky, which is impressive. I know that when Zelefsky left, she was promoted. I think she will do a great job . Sean McBride is their SBRT maven. I was only mentioning MR-linac because of your unique situation, but you are in great hands at MSK.

[BeHealthi in reply to Tall_Allen]

Tall_Allen, someone I know had treatments with dr. Zelefsky and I think his profile is impressive. What’s your opinion about him?

[Tall_Allen in reply to BeHealthi]

The best.

[Infamous9597 in reply to Tall_Allen]

Thank you TA.

I just read about lymphopenia after whole pelvic radiation (healthunlocked.com/advanced... , and it sounds dreadful. Do you think it would be a good idea to just do prostate-only SBRT right now and save the whole pelvic SBRT for when the cancer recurs? Isn't this the same approach as doing salvage radiation for the whole pelvic area if prostatectomy fails?

[Tall_Allen in reply to Infamous9597]

IMO, silly to worry about that. Salvage always creates more side effects than doing it right the first time.