A new book Prostate Cancer Decoded by Robert L. Bard, MD(available on Amazon) explains how HIFU (High Intensity Focused Ultrasound) treats prostate cancer with laser surgery after an MRI which shows precisely where to employ the focus. It has apparently been extremely successful even when used for men who have already had a prostatectomy and/or radiation and/or chemo or hormone treatments in the cases where the cancer (if not metastasised) still exists or reappears.
Apparently at this point because FDA hasn’t approved the approach the only access in the US is in NYC where a sonogram will diagnose prostate cancer that has not yet metastasised. The HIFU procedure is available in Canada and men from the US are being sent to Toronto in that regard.
The above book covers the whole subject of responses to prostate cancer very well.