| Popis: |
Prostate specific antigen (PSA) is the main tool in the follow-up of prostate cancer patients after definitive therapy. It's widely used as an early marker to value treatment success. Biochemical recurrence predicts metastatic disease progression and prostate cancer-specific mortality. In 1996, the American Society for Therapeutic Radiology and Oncology (ASTRO) provided a definition of biochemical failure after radiotherapy, based on three consecutive increases in PSA after nadir. As more experience was gained using the proposed definition and follow up duration in the PSA era matured, deficiencies and controversial issues emerged, so more recently proposed candidate definitions have provided consistent outcome. In view of the criticisms, a second consensus conference was held on 2005, with "nadir + 2 ng/ml" accepted as standard definition. The natural history and evidence of PSA kinetic parameters and different definitions of biochemical failure after external beam radiation therapy and/or brachytherapy are reviewed in the following article. |
