Multicenter evaluation of an artificial neural network to increase the prostate cancer detection rate and reduce unnecessary biopsies.
BACKGROUND
The percentage of free prostate-specific antigen (%fPSA) has been shown to improve specificity for the diagnosis of prostate cancer (PCa) over total PSA (tPSA). A multicenter study was performed to evaluate the diagnostic value of a %fPSA-based artificial neural network (ANN) in men with tPSA concentrations between 2 and 20 microg/L for detecting patients with increased risk of a positive prostate biopsy for cancer.


METHODS
We enrolled 1188 men from six different hospitals with PCa or benign prostates between 1996 and 2001. We used a newly developed ANN with input data of tPSA, %fPSA, patient age, prostate volume, and digital rectal examination (DRE) status to calculate the risk for the presence of PCa within different tPSA ranges (2-4, 4.1-10, 2-10, 10.1-20, and 2-20 microg/L) at the 90% and 95% specificity or sensitivity cutoffs, depending on the tPSA concentration. ROC analysis and cutoff calculations were used to estimate the diagnostic improvement of the ANN compared with %fPSA alone.


RESULTS
In the low tPSA range (2-4 microg/L), the ANN detected 72% and 65% of cancers at specificities of 90% or 95%, respectively. At 4-10 microg/L tPSA, the ANN detected 90% and 95% of cancers with specificities of 62% and 41%, respectively. Use of the ANN with 2-10 microg/L tPSA enhanced the specificity of %fPSA by 20-22%, thus reducing the number of unnecessary biopsies.


CONCLUSIONS
Enhanced accuracy of PCa detection over that obtained using %fPSA alone can be achieved with a %fPSA-based ANN that also includes clinical information from DRE and prostate volume measurements.
Stephan
Carsten
C
Department of Urology, University Hospital Charité, Humboldt University, D-10098 Berlin, Germany. carsten.stephan@charite.de
Cammann
Henning
H
Semjonow
Axel
A
Diamandis
Eleftherios P
EP
Wymenga
Leon F A
LF
Lein
Michael
M
Sinha
Pranav
P
Loening
Stefan A
SA
Jung
Klaus
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy / Q000592:standards; D006801:Humans; D008297:Male; D008875:Middle Aged; D016571:Neural Networks, Computer; D017430:Prostate-Specific Antigen / Q000097:blood* / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D012372:ROC Curve; D012680:Sensitivity and Specificity
D017430:Prostate-Specific Antigen