Visible Changes After Prostate SBRT

If you have to do any ADT after SBRT your genitals will temporarily and noticeably shrink. Mine returned to mostly normal within six months.

Since my SBRT treatment, the base of my penis has become narrower when erect (my sexual health doctor calls it "cobra penis" which is a type of Peyronie's). It hasn't interfered with function in any way, and the doctor says it doesn't need treatment at this time. It's much more noticeable to me than to a partner. My oncologist insists radiation does not cause this. The actual answer seems more nuanced.

Here's what my personal research found:

• Radiation causes fibrosis in nearby soft tissues. Scar-like stiffening can happen in the perineum, around the crura (the internal part of the penis that sits near the prostate), or around the suspensory structures. That can slightly “pull in” the base or reduce elasticity when erect.
• ADT and radiation together shrink penile tissue volume temporarily. Some men get diffuse loss of girth that later recovers unevenly.
• Reduced blood flow at the base (because the proximal cavernosal arteries take some spray from the radiation field) can lead to less expansion at that specific segment during erection.
• A form of Peyronie’s triggered by micro-trauma + post-radiation healing can happen, even though many rad oncs deny it.

@4rbest
You don't mention your Gleason or biopsies I assume those have already been done.

Are you going on homone treatments? Hormone treatments would have a far more side affect to you that SBRT.

You mentioned SBRT. I assume this is with photon radiation not proton. If you don't know the difference you need to research it as they are very different types of radiation and controlling the radiation beam.

I did not have hormone treatments so cannot comment on personal experience with side affects from this type of treatment. I had 30 rounds of proton radiation. I did have side affects (minor) of increased urination and urgency but I did not notice any change to my penis.

You mentioned what your wife will see. I can tell you that proton radiation is ususally done with beam entering the sides of your body by your hip. You will get what looks like a sunburn there on both sides after time. My wife saw it and I had not told her about to expect it so she did kind of freak out. The sunburn is caused by radiation entering the body and will last for some time even after but eventually will go to tan and then goes away compleately after time (after radiation stops).

Just a footnote on proton and photon radiation. Photon enters body a full force, hits the targets and continues through the body. Proton radiation can enter the body at lower dose, release is full dose at targeted area and stops. It (proton) does not continued through and exit body. So you can see the difference is not in success rates (they are the same) it is the possibility of less damage and secondary cancers to healthing ograns and tissues that photon will hit.

UFHPTI has an excellent information hand out on radiation treatments, that includes tons of research, their program, and two books (one is the Walsh book on surving PC) that is free and will be sent to you regardless of you deciding to go there or even consider going there.
Good luck!!

@scottbeammeup mine are very very slowly going back to normal too after ADT cessation in January 2025. AGE is 77. Last months testosterone was 59. FYI to compare.

My husband had RP and there are no changes in size or look or anything remotely close that assumption.

Regarding RT - there should be no changes as @scottbeammeup explained and they are rare, except if you have to use ADT. ADT usually causes many changes in body in general and returning to "normal" depends of length of usage of ADT, age and many other factors.

I doubt after 5 you will be manscaped.

@jc76 it is from a LINAC machine so I believe photon.

@4rbest
I am not familiar with LINAC machine.

Just in the last 2.5 years I was diagnosed with PC there have been so many new diagnosis and treatment of PC. I just read WEDMD and citing new trials and studies on advanced PC treatments using proton, and target ways to attack PC only not other normal cells.

I hope with all this new advancements PC can with a lot of other diseases become a disease with a cure rate of 100%. What would be even better a way to prevent it.

Howdy - completed SBRT X5 on 7/24/25. No ADT. Absolutely no external change visible & manscaped. Only somewhat bothersome aspect is the dry orgasms. Sort of feels like the flow is pinched off - and while the orgasm is satisfying- it is different and well maybe less explosive if that makes sense.