For many men there comes a time in the treatment process when ADT stops working and the PSA will again begins to rise! Unfortunately, the prostate cancer cells “learn” how to grow without testosterone being present. At this point, we call the cancer androgen independent (AID).
When the cancer does become AID, there are still a number of treatments available. As usual with prostate cancer, there are no clear-cut “best ways” to proceed. However, there is a consensus that prior to moving ahead with formal chemo-therapy using Taxotere you should try a second line hormonal manipulation using antiandrogen withdrawal (AAWD) either alone or in combination with high dose Ketoconazole (Nizoral) plus hydrocortisone or aminoglutethimide (Cytadren).
“In approximately 50% of patients whose cancer has started to grow again despite treatment that includes an antiandrogen, the cancer has been noted to regress by simply stopping the anti-androgen. This unusual response is referred to as the Anti-Androgen Withdrawal Response (AAWR). Scientists theorize that prostate cancer cells exposed to antiandrogens for a prolonged time may mutate (undergo genetic change) that paradoxically causes the anti-androgen to stimulate cancer growth.” –( Prostate Cancer Research Institute)
The question does remain whether or not to just stop the androgen blockade or to stop the blockade and start Ketoconazole. An interesting phase III Trial (CALGB 9583) reported in the Journal of Clinical Oncology, Vol 22, No 6 (March 2004) pp 1025-1033 tried to answer this question. Eric Small, Susan Halabi, Nancy Dawson, et al, authored the trial.
The findings of this trial were that 11% of patients undergoing AAWD alone and 27% of patients who underwent AAWD along with Ketoconazole (K) had a PSA response (p=.0002). Objective responses were observed in only 2% of patients treated solely