FPSA/TPSA比值对前列腺癌的诊断价值

目的 :研究FPSA/TPSA的比值对前列腺癌 (PCa)的诊断价值以及PCa与前列腺增生 (BPH)的鉴别诊断价值 ,了解影响比值的有关因素。　方法 :分别用RIA和ELISA检测FPSA和TPSA ,并计算FPSA/TPSA之比。　结果 :85例正常对照FPSA/TPSA的比值 (x±s)为 0 32± 0 0 9,BPH和PCa的比值分别为 0 2 6± 0 0 8和 0 12± 0 0 6 ;若以 0 16作为比值的cut off值 ,PCa和BPH的灵敏度分别为 91 7%和 7 3 % ,特异度为 95 3 % ,PCa和BPH的鉴别诊断效率高达 92 5 % ;取cut off值为 0 2 5时 ,PCa和BPH的灵敏度分别为 86 %和 8 3 % ,特异度为 92 9% ,PCa和BPH的鉴别诊断效率仅 2 3 4% ;直肠指诊、膀胱镜检查、前列腺活检和标本 4℃存放 1周 ,均可使比值显著升高 ;慢性肾衰病人显著低于正常人。　结论 :FPSA/TPSA比值较FPSA和TPSA均更具诊断和鉴别诊断价值 ,对TPSA在 4 0～ 10 0 μg/L的病人价值更大 ;比值测定影响因素较FPSA和TPSA少。

Diagnostic Value of FPSA/TPSA Ratio in Prostate Cancer

Objectives: To evaluate the value of Free PSA/total PSA(FPSA/TPSA) ratio in the diagnosis of prostate cancer(PCa) and distinguishing PCa from BPH, and study the factors affecting the ratio. Methods: Free and total PSA were respectively detected by using RIA and ELISA, then their ratio(FPSA/TPSA) was calculated. Results: The ratio of FPSA/TPSA (x±s) was 0.32±0.09 in 85 normal controls, 0.26±0.08 in BPH and 0.12±0.06 in PCa, respectively. If using 0.16 as cut off value, the sensitivity was 91.7% and 7.3% in PCa and BPH respectively, the specificity was 95.3% in two groups, and the differential diagnosis efficiency was even up to 92.5%; using 0.25 as the cut off value, the sensitivity was 86% and 8.3% in PCa and BPH respectively, the specificity was 92.9% in two groups, but the differential diagnosis efficiency was only 23.4%. Digital rectal examination, cystoscopy, biopsy of prostate or the samples stored at 4℃ for one week, could lead to an increase of the ratio, but chronic kidney dysfunction lead to a decrease. Conclusions: The ratio of FPSA/TPSA was more valuable than FPSA and TPSA in diagnosing PCa and in differential diagnosing PCa and BPH, especially, in the patients with TPSA in 4.0～10.0μg/L, and the factors affecting the ratio were less, too.