title: [Diagnosis of prostate cancer with PSA < or =4.0 microg/L].
abstract: OBJECTIVE
  To evaluate digital rectal examination (DRE) , transrectal ultrasonography (TRUS) , free/total (f-PSA/ t-PSA) prostate-specific antigen (PSA), and PSA density (PSAD) in the diagnosis of prostate cancer (PCa) in patients with PSA < or = 4.0 microg/L.
  
  
  METHODS
  Between April 1996 and December 2012, a total of 343 subjects, aged 30 -91 years, with PSA < or =4.0 microg/L and abnormal findings on DRE or TRUS underwent prostatic biopsy. Based on the levels of PSA, the subjects were divided into four groups: 0 -1.0, 1.1 -2. 0, 2.1 -3. 0, and 3.1 -4.0 microg/L. The diagnostic values of DRE, TRUS, f-PSA/t-PSA, and PSAD were assessed in those with different PSA levels. According to the age, the subjects were again divided into five groups: C49 yr, 50 -59 yr, 60 -69 yr, 70 -79 yr, and > 80 yr. The rates of PCa detection in relation to PSA levels were estimated in different age groups.
  
  
  RESULTS
  Of the 343 subjects, 65 (19.0% ) were diagnosed with PCa, with detection rates of 16.28% (21/129) , 17. 17% (17/99), 21.82% (12/55), and 25.00% (15/60) in those with the PSA levels of 0 -1.0, 1.1 -2.0, 2.1 -3.0, and 3.1 -4.0 microg/L, respectively. There were statistically significant differences in f-PSA/t-PSA between the PCa patients and non-PCa subjects with the PSA level > 2.0 microg/L (P <0.05) , but not with the PSA level < or =2.0 microg/L (P > 0.05) , nor did PSAD show any significant difference between the PCa and non-PCa groups ([0.09+/-0. 16] versus [0. 06 +/- 0. 07] micro/L/ml, P > 0. 05). The rate of cancer detection rose -with the elevation of the PSA level, but had no statistically significant difference among different age groups (P >0.05).
  
  
  CONCLUSIONS
  PSA 2.1 -4.0 microg/L with abnormal DRE and TRUS findings should be considered as a warning signal, which requires regular follow-up and PSA detection. With f-PSA/t-PSA <0. 15 with or without abnormal DRE and TRUS findings, routine prostate biopsy should be performed. PCa diagnosis cannot be effectively established by DRE, TRUS, f-PSA/t-PSA, and PSAD in those with PSA < or = 2.0 microg/L.
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Jie
authors.initials: J
authors.lastname: Tang
authors.forename: Xiang
authors.initials: X
authors.lastname: Fei
authors.forename: Qiu-Yang
authors.initials: QY
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D006801:Humans; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology
chemical_list: D017430:Prostate-Specific Antigen