title: Mass screening for prostate cancer: a comparative study in Natori, Japan and Changchun, China.
abstract: OBJECTIVE
  To study the natural background of prostate cancer in Japan and China, mass checks with prostate-specific antigen (PSA)-based screenings were performed using identical procedures in Natori, Japan and Changchun, China.
  
  
  METHODS
  For 7 years (1995 to 2001) in Natori, Japan, and for 3 years (1998 to 2000) in Changchun, China, 2212 Japanese and 3566 Chinese men older than 55 years were mass checked by PSA-based screening (serum PSA cutoff value 4.1 ng/mL).
  
  
  RESULTS
  The PSA-positive rates (PSA 4.1 ng/mL or greater) and cancer detection rates in the screened persons of Natori and Changchun were 8.5% and 5.2% (P <0.0005) and 2.1% and 0.8% (P <0.0001), respectively. When the number of cancer cases detected was adjusted to a 100% biopsy rate for men who were PSA positive in both cities, the cancer detection rate was estimated at 2.3% and 1.3% in Natori and Changchun, respectively. This difference was also significant (P <0.01).
  
  
  CONCLUSIONS
  The results indicate that the percentage of PSA-positive men 55 years or older in Changchun was lower than that in Natori. The analysis of the results suggests that the prostate cancer incidence and prevalence in Changchun, China are lower than those in Natori, Japan.
authors.affiliation: Division of Urology, Miyagi Cancer Center, Natori, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kuwahara
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Tochigi
authors.forename: Sadafumi
authors.initials: S
authors.lastname: Kawamura
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Ogata
authors.forename: Ning
authors.initials: N
authors.lastname: Xu
authors.forename: Hongliang
authors.initials: H
authors.lastname: Wang
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhang
authors.forename: Shengwen
authors.initials: S
authors.lastname: Li
authors.forename: Xiaomeng
authors.initials: X
authors.lastname: Li
authors.forename: Xuejian
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000367:Age Factors; D044466:Asian People; D001707:Biopsy, Needle; D002681:China / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008403:Mass Screening / Q000706:statistics & numerical data*; D008875:Middle Aged; D015995:Prevalence; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000453:epidemiology* / Q000473:pathology
chemical_list: D017430:Prostate-Specific Antigen