What side effects have you experienced from SBRT for prostate cancer?

Urinary side effects are down to under 5% "long term" when treating with new RT techniques at centers of excellence. This was told to me by several top urologist & RO's at different COE's. Agree with other poster about people on these forums are here because they are having issues, but many more have minimal side effects and no need to post on forums.

When I finished the SBRT and the urinary and bowel problems started a few days later, I was concerned that they seemed to be increasing and contacted my RO. The nurse responded that my symptoms were very common and would subside in 10 days to two weeks. She was spot on and said "it's just the radiation working its way through your body." I thought that summarized the situation pretty well.

The SpaceOAR and fiducial insertion was a breeze - no side effects at all. I was also given three tiny tattoos on my abdomen so I could be lined up in the same way each day. Ethos does not use MRI imaging but instead uses an adaptive CT scan which adjusts the radiation targets each day based on possible organ shifts. I think the margins are nearly as good as the MRI machines. The time in the machine is a little longer due to the scan time spent on obtaining an updated CT scan and then adapting the radiation targeting to it. My RO said it was the appropriate machine to use although MRI machines were available.

@jd18 That was mentioned early, but seems to have been dropped from the discussion. Sorry to hear about your situation. Hope things get better.

Update 6/19/2026: Just finished the SBRT on the 17th. Everything went well. Heard from the nurses and RTs that SBRT is the default treatment at my hospital and my doctor does them regularly. Still have no idea what all the to and froing was about. Started having GU SEs after my second treatment. Itchy/tingly feeling around the glans/meatus with feelings of urgency. Hesitancy, but able to totally void. Haven't made it through the night yet. As of today, 6/19, things are looking better. The itchy/tingling is mostly gone; I'm back to peeing every 2-3 hours. Still have irritation when urinating and getting up a couple if times per night. Don't know if this it on the SEs or if there is more to come in a couple of weeks. We'll see. The treatment itself was nothing burger. If what I've been dealing with for the last week is my SEs then they were very annoying, but also very tolerable. A little side note. I had of course an 18 core biopsy and the fiducial/spaceoar installation and honestly say they were also nothing burgers. I have friends who told me how horrible both would be and they just weren't. I've dental work done that was worse. Was awake through both. Either I have a high pain tolerance, or my urologist was a wizard.

Now the questions are, are there more SEs to come in a couple of weeks or is this it and did this all work. We'll hope for a no on the first and a yes on the second.

@bens1I think it's mostly a comfort thing for him. He always says I'll do the SBRT, but.... As for a definable reason he believes that the GU SEs of SBRT are much worse than IMRT. I read a lot of studies and don't see that.

I held firm. We did the SBRT.

Reading through the comments I feel lucky. My SEs didn't last long, maybe 4-6 weeks. It must depend on the area being radiated. 1st time was the prostate, lymph nodes and pubic ramus bone, the area was so sensitive it was critical to eliminate any movement so I herehad to do a self enema before heading to the hospital. SE during radiation, fatigue hit me hard on the 3rd day and I ended up sleeping through the weekend. Desire to eat was diminished due to the low gas diet I was on. Post treatments it was the burning urination and changes to bowel movements, but these didn't last more than 2 months. Fast forward 2 years and the second round, the treatment areas were lymph nodes and a hip bone. I didn't have to do the self enemas and the only side affects were fatigue and loose stools. The low gas diet was the hardest part for me as I am a vegetarian and depend on beans and whole grains, which I had to do without.

I did go with the SBRT

Just finished 5 sessions SBRT - cancer contained in capsule. Also been on Lupron for 3 months.
Very, very mild side effects. A 3 day bout of diarrhea and an upset stomach. I do get up more to pee, at night, but I am also hydrating much more.
Hoping the future is like the present!

79+ started Orgovyx @79 2mo. Good health, no meds. This is a good choice if you take no meds. Web site says 431 known drug interactions from mod to severe- does not even include minor.

I have a very high fiber diet for 39 years and no snacks, fast food, alcohol, very little dairy, desserts-just a 8 oz vegan protein drink each night.

Gleason score 7 in all places sampled. PSA 8. Had gold markers and rectal spacer at same time before beginning SBRT. Tell them to give extra numbing around where these go. I did and they ignored me and was a painful experience. But no real side effects afterward although a little difficulty urinating because of swelling of prostate. I regularly have bowl movements every two days, not every day, which is a problem for SBRT since you have to have an empty bowl and full bladder and hold for about 30 minutes from start to finish each SBRT treatment. Actual SBRT is painless and only takes about 10-15 minutes.

I experienced side effects from SBRT from the start with some difficulty urinating and constipation. Finally after the first week (3 treatments), had to get Flow max generic as very painful, frequent, up almost every hour at night. First night on Flow max had a blow out of urine. Get the night time Depends.

Never had diarrhea, loose stools etc. with either Orgovyx or SBRT so far. My urologist says must stay on Orgovyx 2 years. But any side effects dissipate quickly unlike the shots whose side effects can last 2 years after stopping the shots.

After all five, needed 2 flow max/day and a spastic bladder pill. Really big blow out but Depends caught it all. Going to continue this for a while but feel much better. Also taking generic Mira Lax 1/day. At this point, it is just in week 1 after last treatment. Both the laxative an Flow max add to the slight imbalance and fatigue issues you might find with Orgovyx. So far no naushea and continuing my regular diet which includes some spices that they say to limit. This waring might apply more to those who experience diarrhea or other bowl irritation.

Urologist says weight exercises are best for dealing with Orgovyx fatigue. I was a gym rat from age 40 to 66 - 1 hr./da, 6 days a week and sometimes 2 a days. Was very surprised how much strength I had lost so brought up some light weights from basement. At first you look at them and think how can I possibly lift weights? Just start light, maybe 8 or 10 pounds and do one set and tell yourself OK. I'll do more tomorrow. It is amazing how fast the effect of the weight fixes the fatigue even after 1 set. Really an incentive to get back to weights. Just work on flexibility and high reps (increase to 15-20 before upping weight). But in about 3 weeks you will be excited, increasing weights, reps and sets. You will still feel fatigued each morning until about noon. I lay down after lunch for about an hour and then do weight sets and feel great rest of day. Routine starts all over next day-fatigue, nap, weights. You probably will feel some pain in joints at first because joints are not yet generating extra synovial fluid and tendons are not flexible, but this goes a way if you do not overdue it. After you get the flexibility back, the only pain you get is afterward, the good type of muscle soreness from building muscle. Concentrate on a different body part next day until soreness goes. One non-weight exercise is to lay on floor and do leg lifts and crunches if too sore to do upper body. Also climbing steps in sets, 2 at a time, then start carrying a weight in one hand after a few times of no weight and steps. This really helps bring back aerobic capacity and you will probably have to catch breath after each time up and down steps. Better aerobic capacity also aids recovery between sets.

During SBRT, I was just too tired to do weights, and just stretched to keep flexibility and now ready after one week of ending SBRT to go back to weights. Cycling and walking might help some, but I always found too boring. Same for yoga for me. Nothing like pumping iron.

I’m 3 months since my last SBRT session with minimal side effects. Some initial urgency with urination that was short lived. Nothing else to report so far, hopefully the delay effects will pass me by. No issues with energy or physical activity. My first post radiation PSA is set for December (6 months after SBRT). No need for meds except flomax- generic which I started 18 months before prostate cancer diagnosis (7= 3+4). Very satisfied with the SBRT decision even though my initial urologist was pushing for surgery. Good luck with your journey; stay positive.

It is absolutely fabulous that people are reporting no side effects at 3 days and 3 months. We have to realize it can take years for side effects to manifest.
I am at 32 months, I was treated at age 68. I have been at Flowmax since treatment began and my urinary function is better than it was before treatment. No ED, albeit essentially dry ejaculation. I was on ADT for 6 months and had manageable hot flashes, some muscle ache, but no brain fog. Rigorous daily gym visits and walking 18 holes of golf twice a week allowed me to be relatively fatigue free and maintain muscle mass.
During the actual two week treatment period I had bowel urgency a couple times, but no related accidents( if you will). For me. SBRT with ADT was essentially a piece of cake especially compared with what other cancer patients are put through.

Stay Strong Brother, We Got This