• Serum PSA is commonly used in prostate cancer patients to assess response to definitive local therapy and to detect relapse after definitive treatment in localized disease • A low PSA nadir is associated with longer survival after endocrine treatment of metastatic prostate cancer, though survival predictions from PSA parameters are not accurate • Though PSA is used to evaluate response to chemotherapy and in clinical trials assessing new drugs in prostate cancer, it is unclear whether decline in serum PSA is a surrogate for overall survival • Physicians should be aware of the...

• Serum PSA is commonly used in prostate cancer patients to assess response to definitive local therapy and to detect relapse after definitive treatment in localized disease • A low PSA nadir is associated with longer survival after endocrine treatment of metastatic prostate cancer, though survival predictions from PSA parameters are not accurate • Though PSA is used to evaluate response to chemotherapy and in clinical trials assessing new drugs in prostate cancer, it is unclear whether decline in serum PSA is a surrogate for overall survival • Physicians should be aware of the postchemotherapy PSA surge syndrome during the first weeks following chemotherapy for CRPC, to preclude early discontinuation of chemotherapy in the erroneous assumption that progression has occurred.