SBRT (MRI) Side Effects

@glabelle

I had SBRT but specifically the Mridian machine, 5 treatments, with 2 mm margins so healthy tissue exposure was less than other sbrt machines that used 3-5 mm. After the 3rd treatment, my urination was a bit more difficult, so I started Flomax and overnight my stream increased. There have not been any additional side effects other than over time (I was treated in Jan-Feb of 2023), my urination flow improved.

My brother had five sessions of SBRT and had similar problems with urination to what you have. This problem went on for maybe three or four months, and then things went back to normal. Flomax did work for him, though it was not a perfect solution at first.

Basically the same issues you describe, plus tiredness. After two months I didn't need Flowmax anymore. The fatigue went away after about 3 months--would take a nap in the afternoon if it got too bad.

I wonder if lengthening the interval from alternate days to two days per week or once weekly might reduce the acute urinary symptoms.? The PROSTox (MiraDx) test is geared to determine if delayed onset urinary tract symptoms may occur. [15% HIGH or < 5% LOW risk for either or both (SBRT/IMRT)]. The delayed intervals may also apply to this group as well.

Interesting comment you make on frequency of individual SBRT treatments. Originally I was told 5 treatments every other day. Then, I was told 5 treatments on five consecutive days, which is what I had. I’ve wondered why the change and if the consecutive 5-day treatment plan causes a higher incidence of side effects. I did take the DNA test and came back low risk. Maybe that is why they went 5 consecutive days?

One of the reasons that I did not go with the shorter 5-sessions of radiation was due to the reported higher risk of urinary bother with the higher radiation dose each session (though I did use Tamsulosin throughout my treatments just in case)..
> Flomax (Tamsulosin) will help relax tissues in the bladder and prostate, allowing you to urinate more during the day.
> Limit your fluid intake many hours before bedtime.
> You’re already taking ibuprofen; perhaps a different NSAID (Alleve/Advil/Naproxin/Motrin) will work better for you?
> Consider trying a prescription strength NSAID (Celebrex), perhaps that may work better.
> You should try that prescribed 6-day course of steroids (Medrol dose-packs); that’s supposed to work better than all the others above.

Is there also any pain and burning during urination (dysuria)?

Thank you for the suggestions. I haven’t experienced dysuria.

I’m two years out from the same treatment with adt. I also had the same issue when finished. Brace yourself, this was the first of the side effects. I also took Flomax as well, which helped. At first, if I had to go I had to make sure I could sit down because both ends would open, eventually things got better and I was able to “retrain” myself to go without worry. I then stopped the FlowMax and now I’m able to go as “normal”. Recently, I decided to go back to using FlowMax as I was still having to get up multiple times in the night to pee. They do help and I only need to get up once or twice now. Just remain calm and try to remain positive, the issue will subside. All I can add is to be ready for other side effects.

my RO at moffit said he would consider a prednisone taper post HDR.
additionally, he would rx celebrex post sbrt.
side effects from steroid do taper down with the dose.
always consider drug interactions, contraindications, comorbidities. for instance., steroids can raise blood sugar temporarily.

If you don’t do a taper of prednisone, you will find great fatigue in the Afternoon. Almost nothing will be able to keep you from falling asleep. That’s the problem with prednisone and not tapering it over a long enough period.

That taper can take two or three months to actually allow your body to adjust and start producing more cortisol.