title: The relationship between prostate-specific antigen and TNM classification or Gleason score in prostate cancer patients with low prostate-specific antigen levels.
abstract: BACKGROUND
  Prostate-specific antigen (PSA) is a useful biomarker for risk classification in patients with prostate cancer. However, it is unclear whether a correlation exists between low PSA levels (<10 ng/ml) at diagnosis and prognosis.
  
  
  METHODS
  Of the 642 Japanese patients who underwent prostate biopsy and were diagnosed with prostate cancer at Kanazawa University Hospital from 2000 to 2010, 406 patients with a PSA level <20 ng/ml were retrospectively reviewed.
  
  
  RESULTS
  PSA levels in 275 (68%) patients were <10 ng/ml. Although the percentage of Gleason score 8-10 in patients with a PSA level of <3.5 ng/ml was higher than that in patients with a PSA level between 3.5 and 10 ng/ml, it was not statistically significant. On the other hand, the percentage of higher stage (T3 and T4) patients with a PSA level <3.5 ng/ml was significantly greater than that in patients with a PSA level between 3.5 and 10 ng/ml (P < 0.0001). The percentage of metastases (N1 and M1) in patients with a PSA level <3.5 ng/ml was also significantly higher than that in patients with a PSA level between 3.5 and 10 ng/ml (P = 0.0112).
  
  
  CONCLUSIONS
  Patients with prostate cancer with a PSA level <3.5 ng/ml at diagnosis had a more advanced stage of cancer compared with those with a PSA level between 3.5 and 10 ng/ml. Therefore, risk classification using PSA levels at diagnosis may need to take into consideration this specific PSA range in order to better predict survival.
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Kouji
authors.initials: K
authors.lastname: Izumi
authors.affiliation: Division of Pathology, Kanazawa University Hospital, Kanazawa, Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Ikeda
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Aerken
authors.initials: A
authors.lastname: Maolake
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Machioka
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nohara
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Kazutaka
authors.initials: K
authors.lastname: Narimoto
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Ueno
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Kadono
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Kitagawa
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Konaka
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mizokami
authors.affiliation: Department of Integrative Cancer Therapy and Urology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
authors.forename: Mikio
authors.initials: M
authors.lastname: Namiki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D006801:Humans; D007564:Japan; D007610:Kallikreins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging / Q000473:pathology; D009367:Neoplasm Staging; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology*; D011859:Radiography; D012189:Retrospective Studies
chemical_list: D014408:Biomarkers, Tumor; C549870:KLK3 protein, human; D007610:Kallikreins; D017430:Prostate-Specific Antigen
keywords: Gleason score; PSA; TNM; prostate cancer