The hormonal therapy is working. When a body is depleted of the T levels it's not uncommon for the PSA to drop completely out. I can name a few cases where the PSA was over 1,000 and after HT alone it was zero.
Advanced Prostate Cancer at age 44 (I am 49 now)
pT3b,N0,Mx (original PSA was 19.8) EPE, PM, SVI. Gleason 4+3=7
Da Vinci Surgery ~ 2/16/2007
Adjuvant Radiation Therapy ~ IMRT Completed 8/07
Adjuvant Hormone Therapy ~ 28 months on Casodex and Lupron.