title: Cumulative risk of developing prostate cancer in men with low (≤ 2.0 ng/mL) prostate-specific antigen levels: a population-based screening cohort study in Japan.
abstract: OBJECTIVE
  To investigate the natural history of men with low levels of baseline prostate-specific antigen in terms of risk of increased prostate-specific antigen, developing prostate cancer and also the likelihood of detecting clinically insignificant cancer in population-based screening.
  
  
  METHODS
  A total of 10,653 men aged between 55 and 68 years with baseline prostate-specific antigen levels of 2.0 ng/mL or lower screened annually were enrolled. The cumulative risks of increased prostate-specific antigen and developing cancer were investigated. The relationships of baseline prostate-specific antigen with clinicopathological features of screening-detected cancer were also investigated.
  
  
  RESULTS
  A total of 1405 men (13.2%) showed serum prostate-specific antigen above 2.0 ng/mL and 68 (0.6%) were diagnosed with prostate cancer during the observation period. Cumulative probabilities of increased prostate-specific antigen above 2.0 ng/mL over 10 years were 7.7%, 18.3%, 57.3%, and 88.7% in men with baseline prostate-specific antigen levels of 0.0-0.5, 0.6-1.0, 1.1-1.5, and 1.6-2.0 ng/mL, respectively. The cumulative probabilities of developing prostate cancer at 4 years in men with baseline prostate-specific antigen of 0.0-1.0 and 1.1-2.0 ng/mL were 0.05% and 1.10%, respectively. Patients with unfavorable clinicopathological features were diagnosed at 3 years, and at 1 year after the initial screening visit in men with baseline prostate-specific antigen levels of 0.0-1.0 and 1.1-2.0 ng/mL, respectively.
  
  
  CONCLUSIONS
  The cumulative probabilities of increased prostate-specific antigen and developing prostate cancer significantly increase with higher baseline prostate-specific antigen ranges. Our database could contribute to the establishment of a natural history-adjusted screening system in the future.
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Graduate School of Medical Science, , Kanazawa University, Kanazawa, Ishikawa, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Sawada
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Kitagawa
authors.forename: Kazuto
authors.initials: K
authors.lastname: Ito
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Takeda
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mizokami
authors.forename: Mikio
authors.initials: M
authors.lastname: Namiki
mesh_terms: D000368:Aged; D015331:Cohort Studies; D055088:Early Detection of Cancer; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000175:diagnosis; D012306:Risk
chemical_list: D017430:Prostate-Specific Antigen
keywords: prostate cancer; prostate-specific antigen; risk factor; screening