Is 60 Gy / 20 fractions “strong enough”?

Yes, the biological effects of the Gys is greater with increased dose per fraction. So 3x20 has about the same effect as 2.5x28 even though the total Gys are less. With SBRT it is usually 8gys x 5 for a total of 40, and sometimes even 7x5.

That's a "curative dose" (it's the level of dose they give when the *intent* is to cure rather than just palliate pain, even though it's impossible ever to know for sure if your cancer is cured).

For my Gleason 7(4+3) w/PSA 7.976, they gave me the choice of 20 fractions @ 3.0 grays/fraction (60 grays total), 28 fractions @ 2.5 grays/fraction (70 grays total), or 30 fractions @ 2.0 grays/fraction (60 grays total).

I asked them which they had more success with. They indicated the 28 fractions @ 2.5 grays/fraction. That’s the one I chose.

My RO prescribed 37 txs @1.8 gy per for a total of 66.6 gys (45 gys of which were also directed to the pelvic lymph nodes)
Together with short term ADT
G 9 w/ EPE post-op path findings.

Gratefully undetectable uPSA since Nov 2023. 🤞& 🙏 for continuation.

Best wishes.

@brianjarvis Not sure why 2x30 was offered (insurance limits since they pay by fraction?). Normal is at 37-40 fractions at 2Gys for 74-80 Gys. Still 2.5x28 will work as well or better. The 3x20 is about the same but with a higher percentage of side effects. As a general rule fewer fractions are easier on the schedule, but harder on the body. Need to pay attention to biological effect and not just total Gys. The RO and physicist have a load of calculations to equate different dose schedules (ask). So 3x20=60Gys is good but 2x30 for 60 Gys is underdosed.

External therapy is suboptimal. Internal beam rate therapy avoiding irradiating non prostate healthy tissue can deliver the optimal dose. Seeds aka interstitial radiotherspy aka ‘LDR’ brachytherapy has the best
track record. Go to You-Tube video Brachyherapy 101 to start. It has dropped from 17% to 7% in
the US whereas it is increasing in the EU. It is the lowest $$$

@thmssllvn I have heard that here in the U.S., the insurance reimbursement rates are lower for brachytherapy than for external beam radiation treatments.
(I’m 5 years post-proton radiation treatments. So far, PSA is staying low and have had no adverse after-effects.)