@retireddoc 's link was for Groups 1-3 prostate cancer:

Group 1 = Gleason 6 (3+3)
Group 2 = Gleason 7 (3+4)
Group 3 = Gleason 7 (4+3)

These patients all had radical prostatectomies, and (again, according to the summary posted by retireddoc) there was no statistically-significant difference in biochemical recurrence between the cohorts who did and didn't receive TRT later.

I don't see anything there that would apply to those of us with advanced/metastatic prostate cancer (who would usually be G8 or G9, according to my oncologist, if they even bothered to grade it); presumably the study was just about early-stage cases where the cancer was hopefully eliminated with the prostatectomy. But if additional studies confirm it, it's good news that testosterone treatment might not increase the post-surgery risk for those people.