What are the odds that an orchiectomy will reduce the size of the prostate if you have prostate cancer at 87?

I have had prostate cancer for years, now all of a sudden a new urologist says I need my testicles removed to slow the growth. Unless it will reduce the size of the prostate and allow me to urinate without a catheter, why shouldn’t I just stick with the injections if it accomplishes the same thing chemically? Is there any benefit to surgery that is worth the pain and risk?