Survival benefit of local versus no local treatment for metastatic prostate cancer-Impact of baseline PSA and metastatic substages

To test whether local treatment (LT), namely radical prostatectomy (RP) or brachytherapy (BT) still confers a survival benefit versus no local treatment (NLT), when adjusted for baseline PSA (bPSA). To further examine whether the effect of LT might be modulated according to bPSA and M1 substages.