Casodex causing increasing psa

Has anyone experienced a rising psa after initiating Casodex therapy. After having Robotiic surgery, IMRT, and 12 months of Firmagon shots, I have never had a psa >.1. After 12 months of Firmagon and 5 psa all <0.1, I decided to take a vacation period. 5 months later my psa was 0.33. I resumed the Firmagon and the psa dropped to 0.32. My Onc then decided we should add Casodex. One month later psa 0.43. Continued the same and now, 4/9/14 psa 0.76. I want to stop now and see what the psa is in one month. If it drops, I may experience a anti-androgen response but if it icreases than switch to Nilutamide or Zytiga. My medonc wants to continue with the Casodex. Now he is discussing biochemical failure and CRPC. If Casodex is contributing to the increasing psa and the psa were to have continued to drop on Firmagon alone, these scary discussions would be moot. All previous indicators, T levels, duration < 20, psa nadir, duration of nadir, indicate no need to worry about CRPC until 5- 7 years. Neg bone scan in April. T- < 20. DHT <1.0 Gleason 4+5. Appreciate any input. pmikey