title: Change in the ratio of free-to-total prostate-specific antigen during progression of advanced prostate cancer.
abstract: BACKGROUND
  The ratio of free-to-total prostate-specific antigen (PSA) is different in benign prostatic hyperplasia and in the early stage of prostate cancer. The present study was undertaken to examine the ratio of free-to-total PSA in the advanced stage of this cancer and its subsequent change during course of the disease.
  
  
  METHODS
  Free and total PSA were measured in sera collected from the following patients with benign and cancerous prostatic diseases: 47 cases of benign prostatic hypertrophy, nine in TIC with less than 10 ng/mL of total PSA, 11 in stage C, 16 in D2, 22 in remission under endocrine therapy, and 12 in relapse. In addition, PSA was measured sequentially in four other patients who were also in relapse.
  
  
  RESULTS
  The ratio of free-to-total PSA was similar in early and advanced stages of untreated prostate cancer and was lower than that in benign prostatic hyperplasia. The ratio increased to the level of benign prostatic hyperplasia during remission from stages C and D2 under endocrine therapy. There was no correlation with the intervals from the start of the therapy to examination. Following relapse, the ratio came down gradually to the level obtained in untreated prostate cancer.
  
  
  CONCLUSIONS
  The ratio of free-to-total PSA was similar in all stages of untreated prostate cancer. Response and relapse to endocrine therapy were associated with increase and decrease in ratio, respectively.
authors.affiliation: Department of Urology, Asahi General Hospital, School of Medicine, Chiba University, Japan. aghp1326@a1.mbn.or.jp
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: S
authors.initials: S
authors.lastname: Murakami
authors.forename: N
authors.initials: N
authors.lastname: Suzuki
authors.forename: J
authors.initials: J
authors.lastname: Shimazaki
mesh_terms: D018450:Disease Progression; D006801:Humans; D008297:Male; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D017430:Prostate-Specific Antigen / Q000097:blood*; D011470:Prostatic Hyperplasia / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology* / Q000628:therapy
chemical_list: D017430:Prostate-Specific Antigen