[Free/total ratio of prostate-specific antigen (PSA) for prostate cancer detection in patients with gray zone PSA level].
Thirty seven patients complaining of voiding disturbance who showed gray zone total prostate-specific antigen (t-PSA) level (upper limit of normal approximately 10 ng/ml) but did not reveal apparent cancerous findings in the prostate were examined for free PSA (f-PSA) and prostate volume. According to histological diagnosis, 9 were cancer cases and the other 28 were non-cancer cases. The free/total (F/T) ratio was 0.10 and 0.16 in the cancer and non-cancer groups, respectively (t-PSA; DPC kit, p = 0.03). The t-PSA (DPC and Dinabott kits), f-PSA and PSA density alone did not distinguish these two groups. For diagnosis of cancer, the ratio seemed to be F/T, the most reliable followed by PSA density and t-PSA. When using a 13% F/T, the sensitivity and specificity for cancer detection were 88.9 and 70.8%, respectively. t-PSA measured with the Dinabott kit, showed a similar tendency except that the F/T ratio showed a slight variation. Prostate volume and patient age influenced the F/T slightly, but these factors may not impair the usefulness of F/T.
Tanaka
M
M
Department of Urology, Asahi General Hospital.
Murakami
S
S
Igarashi
T
T
Abe
T
T
Suzuki
K
K
Sekita
N
N
Shimazaki
J
J
D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008875:Middle Aged; D017430:Prostate-Specific Antigen / Q000097:blood*; D011470:Prostatic Hyperplasia / Q000175:diagnosis; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D011933:Reagent Kits, Diagnostic / Q000592:standards; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; D011933:Reagent Kits, Diagnostic; D017430:Prostate-Specific Antigen