Year of treatment as independent predictor of relapse-free survival in patients with localized prostate cancer treated with definitive radiotherapy in the PSA era

Conclusions: Independent of tumor stage, radiation dose, failure definition, and follow-up parameters, the year in which RT was performed was an independent predictor of outcomes. These findings indicate a more favorable presentation of localized prostate cancer in current years that is not necessarily reflected in the patients' PSA levels or Gleason scores. This phenomenon is probably related to a combination of factors, such as screening, increased patient awareness leading to earlier biopsies and earlier diagnosis, more aggressive pretherapy staging, and unrecognized improvements in therapy, but perhaps also to changing tumor biology. Outcomes predictionsshould be based on contemporaneous series. Alternatively, the year of therapy could be incorporated as a variable in outcomes analyses of localized prostate cancer patients treated in different periods within the PSA era.