SBRT, what has your monitoring protocol been like?

[u/SophieMasloff]

As I understand it, the primary risks associated with SBRT are some very mild secondary toxicity and a more difficult process for monitoring recurrence.

After getting to nadir, how are you being monitored for local or remote recurrence? Is it just PSA or are you getting periodic MRI or PSMA PET scans?

My urologist discussed this with me today and kind of freaked me out, he wasn't pushing surgery and signed me up for a consult but one of his risks associated with SBRT was the difficulty in reacting to a remote recurrence before it advances to a serious issue.

[u/Think-Feynman]

This is one of the tough scenarios that most men face. I'd say that he definitely was low-key pushing surgery by dumping on the other treatments. Not sure why he said monitoring was more difficult.

The truth is, a very high percentage of men who get RALP will have a rough outcome - incontinence, erectile dysfunction, penis length shortening, and a recurrence.

The 5-year biochemical recurrence rate is about 25%, and rises thereafter. The standard treatment at that point is radiation.

For SBRT (I had CyberKnife), the immediate risks of ED are low, with incontinence not really being an issue. Recurrence rates based on stage:

• Low-risk: < 5% at 5 years.
• Favorable intermediate-risk: < 10% at 5 years.
• Unfavorable intermediate-risk: < 25% at 5 years. [1, 2, 3]

Any treatment has a biochemical recurrence risk. This is why you do PSA monitoring. I'm at .07 and still falling after 3.5 years past my last treatment. I am officially in remission. If I have a rise, they will retest, and if it still shows a rise, they will do other diagnostics like PSMA PET scan. That's pretty standard for any treatment. And there is a PSA bounce that you can get, which is common in the first year or so, but I didn't have one.

Stereotactic Body Radiation Therapy (SBRT): The New Standard Of Care For Prostate Cancer

https://codeblue.galencentre.org/2024/09/stereotactic-body-radiation-therapy-sbrt-the-new-standard-of-care-for-prostate-cancer-dr-aminudin-rahman-mohd-mydin/

Urinary and sexual side effects less likely after advanced radiotherapy than surgery for advanced prostate cancer patients

https://www.icr.ac.uk/about-us/icr-news/detail/urinary-and-sexual-side-effects-less-likely-after-advanced-radiotherapy-than-surgery-for-advanced-prostate-cancer-patients

Prostate radiation only slightly increases the risk of developing another cancer

https://med.stanford.edu/news/all-news/2022/070/prostate-radiation-slightly-increases-the-risk-of-developing-ano.html

CyberKnife - The Best Kept Secret

https://www.columbian.com/news/2016/may/16/cyberknife-best-kept-secret-in-prostate-cancer-fight/

[u/SophieMasloff → u/Think-Feynman]

awesome post. TY

[u/Maleficent_Break_114]

Yeah, there is a risk in that occurring with SBRT but now did he fail to tell you that the very same odds will occur even with RALPing it?

[u/SophieMasloff → u/Maleficent_Break_114]

yeah he did but his point was that radiation was available in that event and re-irradiation in local recurrence can carry higher risks for secondary cancers.

I'm mostly interested in how the monitoring is done to ensure I can response proactively and preferably not just rely on PSA

[u/WalnutRoasted → u/Maleficent_Break_114]

Monitoring would be similar for EBRT (including SBRT) and RP surgery.

If you look at North of Lake Ontario protocols, https://www.cancercareontario.ca/sites/ccocancercare/files/assets/CCOProstateFollowUpPathway.pdf page 3, you will see it is pretty much the same for both: PSA every 3 months, then 6 months, then every 12 months. Yes the nadir and acceptable PSA are a bit different. Usually: PSMA-PET is an expensive procedure with long wait times and used for monitoring there is an unexplained (rapid) rise in PSA.

I’m 15 months past EBRT (choice of 5x SBRT and 20x VMAT) and all systems down there doing very well.

[u/PSA_6--0]

I have had it easy. I ended up with rather heavy radiotherapy (no side-effects though) and three months of ADT. At the end of radiotherapy my PSA was 0.1. There was some fluctuation after that but never over 0.1 after that. Now been at <0.02 (the limit of my lab) for a while, now 4 years after treatment.

You can be sure that if I would get a PSA result like 0.2 now I would be in contact with my medical team.

I know other guys with notably higher stable point. But it is possible to have an easy case also. And the guys with rising values have had PET scans done, so that they know they have no visible metastases.

And regarding your question I am doing PSA every three months, at this point my medical team would be happy with twice a year check.

[u/SophieMasloff → u/PSA_6--0]

good feedback. TY

[u/Cheap_Flower_9166]

Exactly. So disingenuous. You need to learn a lot more before deciding. This is a good place. I’d fire the uro.

[u/BlinBlinski]

I don’t think i’ve reached my nadir yet - original treatment 18 months ago - but have had 3-monthly psa tests and two psma/pet scans when there were marked increases in psa levels (both negative fortunately - no recurrences).

[u/OkCrew8849]

Post radiation and post surgery it is “follow the PSA”. for both. And both may include PSMA, when indicated.

The substantive differences involve cancer control, physical recovery, and preservation of sexual and urinary functions. (Hopefully your urologist also explained these in [accurate] detail.)

[u/C63Sedan]

Depends on how advanced and response to treatment. At MSK I get my PSA checked every 3 months and PET scan after 6 months. Scans are not reliable as they can’t always find all evidence of cancer so PSA is the indicator I was told.