I Have Metastatic Prostrate Cancer Since 3 Years ( Gleason

I have metastatic prostrate cancer since 3 years ( gleason level3) and have been taking Pamorelin 11.25 injection q3 and initial 3 months Tabi (bicalutamide 50 mg) since three years. My bone scan for three consecutive years do not show any reduction in locations and intensity and there is no new lesion. My PSA level is 0.05 since three years. once after 20 months my psa level bounced to 0.211 but after taking biclutamide for 3 months came back to 0.05.
my question is that if my bone scan does not show any improvement or deterioration should I use pause therapy( discontinue injection for some time till psa jumps to some predetermined level