PSA response graph from our original "Virtual HDR" Prostate Cyberknife SBRT trial, updated as of March 2011. The median PSA value after treatment in this group of favorable and intermediate prognosis prostate cancer patients continues to decrease out to 4 years, eventually reaching a median "nadir" value of 0.1 ng/mL. Long-term confirmation of the result is still necessary (i.e. - 5-10 years post-treatment), but prior literature for all commonly used radiotherapy methods has repeatedly indicated a favorable long-term outcome when the PSA nadir falls below 0.5 ng/mL, causing us to be very optimistic that the long-term prostate CyberKnife result will be confirmed as favorable. We continue to enroll most of our prostate CyberKnife patients on www.clinicaltrials.gov listed clinical trials, so that me may continue to document and update the long-term results in a larger number of patients. Note: This graph illustrates the median result for our entire study population. Individual patient PSA response patterns may vary significantly from those presented here, especially within the first 1-3 years post-treatment, and should be reviewed with the patient's attending radiation oncologist for most accurate interpertation.