I was diagnoised with stage 4 prostate cancer in April 2024, started Zoladex and Apalutamide in May and had SBRT in September the same year. My PSA has since been dropping from 85 to 0.042 ( June 2026). Things look good for me until recently when I discovered blood in stools. I see blood almost every other day, either in the form of blood streaks in stool or simply bleeding that wet the underwear. My doctor said it is likely SBRT induced. But how could that happen more than 2 years after? I am 87 3/4 and in relatively good shape except some Apalutamide side effects of tireness and hot flashes. Has that happened to anyone of you? Thank you in advance for sharing your experience.
Hello hkcl
I am so sorry to read of your issues. Don't forget I am not medically trained and these are just my thoughts:
* One side effect of SBRT is "Rare or mild rectal bleeding may occur" - Well it's a bit late for a side effect and it sounds like it's much more than "rare or mild".
*
My doctor said it is likely SBRT induced
Did he now - and is that your GP who I doubt has very much knowledge of radiotherapy.
* As far as I am aware the correct way to deal with this would be to ask for 2 stool samples and send them off for a "FIT Test" (Faecal Immunochemical Test). The GP normally does this to see what the result is and if invasive testing (a colonoscopy normally) is needed.
and yes, I have had 3 colonoscopies so I am aware of what is involved.
Regardless of your age (I hope I see 87and 3/4!) - I think that's shabby treatment from your GP and I think you need to be having a word with your Practice Manager. You can't just pass it off as a side effect - clearly you are worried and rightly so.
I hope the above helps - do let us know how you get on.
Best wishes - Brian.

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Hello Brian,
Thanks for the fast response. The " doctor " who made the "SBRT induced" comment is a radiologist of a major Canadian hospital. He has already made referral for me to see a Gastroenterologist. However I have been waiting for more than 3 weeks without hearing from the hospital regarding an appointment date. I have the feeling that they do not consider my case an emergency.
More info about myself: My appetite is normal and my body weight is stable. There is no pain in any part of my body. My concern is, like you said: " a bit late for a side effect".
Thank you again for the comments.
Henry.
Hello hKcl
Just to give an idea of time. My FIT test came within 2 days of being arranged by GP and results within a week if not quicker.
Very Best Wishes to you.
Hello Henry (hkcl )
Thank you for your reply - I don't know how the Canadian medical system works but I would be pushing for a test on the blood in my stools to find out just what it is and where it's come from.
As you say everything else looks OK - if you click on my avatar or my name and read my journey - I was fine, I just went off my food and drink - next thing I am in hospital on death's door!! You need to know where the blood is coming from and the cause!
Yes - "it's a bit late for a side effect".
Good luck and please do let us know how you get on.
Best wishes - Brian.

Macmillan Support Line - 0808 808 00 00, 7 days a week between 8am-8pm
Strength, Courage, Faith, Hope, Defiance, VICTORY.
I am a Macmillan volunteer.
Hi hkcl , obviously any blood needs to be checked out but the causes can be widespread. I first had blood (fresh blood bright red) in my stools about a year after standard RT. A colonoscopy identified radiation proctitis which got worse over the next few years but after about 6 years started to reduce. Other simple causes of blood are piles and diverticulitis. I still (after 8 years since RT) am shocked when I see the loo red, but have come to realise that a small amount of blood can look quite alarming. Watch out for anemia if you lose too much blood.
Best wishes, David
Please remember that I am not medically trained and the above are my personal views.
Hi, hkcl,
Three years after rt I started getting rectal bleeding, radiation proctitus was diagnosed following a colonoscopy. The oncologist said it can happen many years after the treatment. It improved over the years but last year I had vmat rt to all the pelvic lymph nodes so it has worsened again but controlled with suppositories,
Geoff
Hi hkcl,
The medication is prescription but its important to confirm that it is radition proctitis then the correct medication can be prescribed, in my case it was by having a colonoscopy. there are several different treatments available depending on the severity of the condition.
Geoff
Hi again Henry, after a few colonoscopies I was diagnosed with mild radiation proctitis. The Dr suggested leaving it alone although he did mention that there was a possible treatment for more severe cases, involving some laser I think, but he indicated there were risks. In my case, I also had piles and diverticulitis (a previous condition diagnosed 20 years ago), so the medics were unsure about which one of these options was causing the blood.
As others have said, diagnosis of the cause is essential before looking to possible treatments. Although it is disturbing to see blood, it hasn’t caused me any problem and is now getting better with occurrences now over a month apart.
Best wishes, David
Please remember that I am not medically trained and the above are my personal views.
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