Hi Carlos. According to my Oncologist, a 50% drop in PSA, so soon after completion of SRT, is a good sign that the radiation has found it's intended target. I had a similar result after my SRT and the result thus far has been good. Hopefully your PSA will go down further in the month to follow. Best of luck to you.
PSA 7.9, Gleason Score 3+4=7, 2 of 8 positive
open RP Nov 06, T3a, Gleasons 3+4=7, Seminal vesicles and lymph nodes clear
Catheter out 15 Dec 06, Dry since 11 Feb 07
All PSA tests in 2007 (4) <.04
PSA tests in 2008: Mar.=.04; Jun.=.05; Sept.=.08; at SRT Start=0.1,
Salvage RT completed (33 days-66Gy) 19 Dec 08
PSA: in Jan 09 =.05, all tests to date (Jan 11) <.04