[The application of complexed PSA and its relative indexes in the diagnosis of prostate cancer].
OBJECTIVE
To investigate the applicable value of complexed prostate-specific antigen (PSA) in the diagnosis of prostate cancer.


METHODS
From July 2001 to May 2002, 152 consecutive patients (21 were prostate cancer and 131 were benign prostate hyperplasia proved by pathologic diagnosis) whose serum total PSA (TPSA) ranged from 0.2 microgram/L to 21.9 micrograms/L were accessed. The measurement of total PSA, free PSA (FPSA) and complexed PSA was performed by chemiluminescence immuno-assay method. The correlation of TPSA and CPSA was analysed by SPPS 10.0. The receiver operating characteristic curves were generated by plotting the sensitivity versus specificity.


RESULTS
Area under the curve was calculated for each assay. Logistic regression analysis was used to evaluate the ability of CPSA, TPSA and FPSA/TPSA. Area under the ROC curve of CPSA, TPSA and FPSA/TPSA ratio were 0.811, 0.799 and 0.376, respectively. The specificity for the complexed PSA, TPSA and FPSA/FPSA ratio were 62%, 57% and 4.7%, respectively, at cutoffs yielding 95% sensitivity. CPSA was determined to be the best index among the three ones by logistic regression analysis.


CONCLUSIONS
The CPSA and TPSA level in serum may provide good differentiation effect of prostate cancer and benign prostate hyperplasia than FPSA/TPSA ratio. The CPSA performs better than TPSA. At the same sensitivity, CPSA has higher specificity.
Chen
Zhao-Hui
ZH
Department of Urology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430022, China.
Zhao
Jun
J
Wu
Jian-Min
JM
Xiao
Chuan-Guo
CG
D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000032:analysis*; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D012680:Sensitivity and Specificity
D017430:Prostate-Specific Antigen