title: Prostate-specific antigen (PSA) and radiotherapy in locally confined prostate cancer.
abstract: BACKGROUND
  During the last years, prostate-specific antigen (PSA) has been established as the most important tumor marker for prostate cancer. The aim of our study was to evaluate the response of PSA during and after radiotherapy of prostate cancer.
  
  
  METHODS
  From 1/95 to 6/97, 26 patients were irradiated for locally confined prostate cancer (11/26 patients primarily and 15/26 patients after radical prostatectomy). Radiation therapy was carried out with a linear accelerator with a total dose of 60 Gy to the prostate bed. PSA values were measured immediately before, weekly during radiation therapy and every three months after in the usual follow-up pattern.
  
  
  RESULTS
  During radiotherapy, median PSA values fell and continued to fall after radiotherapy. The median PSA half-life was reached 3 months after irradiation, the PSA nadir after 15 months. 5 patients with increasing PSA levels relapsed.
  
  
  CONCLUSIONS
  During and after radiotherapy, PSA kinetics are low with a median half-life of 3 months in our patient population. Rising PSA profile indicates progression of tumor.
authors.affiliation: Department of Radiation Oncology, University of Muenster, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Schaefer
authors.forename: O
authors.initials: O
authors.lastname: Micke
authors.forename: N
authors.initials: N
authors.lastname: Willich
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D005500:Follow-Up Studies; D006207:Half-Life; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009367:Neoplasm Staging; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy* / Q000601:surgery; D011879:Radiotherapy Dosage; D013997:Time Factors
chemical_list: D017430:Prostate-Specific Antigen