title: Evaluation of novel formula of PSA, age, prostate volume, and race in predicting positive prostate biopsy findings.
abstract: OBJECTIVE
  To develop a formula that incorporates age, prostate volume, race, and prostate-specific antigen (PSA) level into a single score for prostate cancer detection.
  
  
  METHODS
  We developed a PSA-age volume (AV) score by multiplying the patient age by the prostate volume and dividing it by the PSA level. The PSA-AV was developed using 1000 prostate biopsy specimens and was validated on 318 internal and 4406 external biopsy specimens.
  
  
  RESULTS
  We analyzed 1000 biopsy specimens (mean age 63 ± 8 years, 63% white and 35% black, mean PSA 6.8 ± 4 ng/mL, mean prostate volume 41 ± 18 cm(3), mean PSA-AV 485 ± 304). Of the 1000 biopsy specimens, 556 (55.6%) had positive findings. A lower PSA-AV score correlated with a greater cancer risk (R(2) = 0.91). A PSA-AV score of 700 had a sensitivity and specificity of 87% and 35%, respectively. These values matched or exceeded the sensitivity and specificity for age-adjusted PSA level and a PSA cutoff of 4 ng/mL. Compared with using the age-adjusted PSA level, using a score of 700 increased the number of biopsies by 64 and detected 62 more cancers. Using a PSA-AV cutoff of 700, rather than a PSA cutoff of 4 ng/mL, led to 16 fewer biopsies with 7 additional cancers detected. Our data were internally and externally validated.
  
  
  CONCLUSIONS
  According to our data, a PSA-AV score has shown to be a useful formula for predicting positive biopsy findings. A PSA-AV score of 700 is useful in ruling out cancer in younger patients and patients with small prostates, and in ruling in cancer in older patients and patients with a large prostate.
authors: Division of Urology, Department of Surgery, University of Alabama at Birmingham School of Medicine, Birmingham, AL 35294-3411, USA.
authors: Shyam
authors: S
authors: Patel
authors: Muta M
authors: MM
authors: Issa
authors: Rizk
authors: R
authors: El-Galley
mesh_terms: D000328:Adult; D001741:Black or African American; D000367:Age Factors; D000368:Aged; D001706:Biopsy; D006801:Humans; D008297:Male; D008433:Mathematics; D008875:Middle Aged; D009929:Organ Size; D011237:Predictive Value of Tests; D011467:Prostate / Q000473:pathology*; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D044465:White People
chemical_list: D017430:Prostate-Specific Antigen