血清总前列腺特异性抗原表达的随龄变化及其在前列腺癌鉴别诊断中的意义

Expression change of serum total prostate specific antigen with age and its significance in differential diagnosis of prostate cancer

目的：探讨血清总前列腺特异性抗原（TPSA）随年龄的变化及其在前列腺癌（PCa）与前列腺增生（BPH）鉴别诊断中的意义。方法采用电化学发光法检测146例PCa、108例BPH及210名健康体检者的TPSA及游离前列腺特异性抗原（FPSA）。结果年龄与血清TPSA水平呈正相关（r＝0.265，P＜0.01）。 PCa与BPH组的TPSA水平分别为（85.40±56.70）μg／L、（7.90±7.00）μg／L，差异有统计学意义（t＝8.310，P＝0.001）；FPSA水平分别为（5.16±4.90）μg／L、（1.50±1.36）μg／L，差异有统计学意义（t＝3.152，P＝0.030）。对于TPSA水平在4.0～20.0μg／L范围“诊断灰区”的患者，PCa和BPH组的TPSA水平分别为（8.82±4.01）μg／L、（8.41±3.95）μg／L，差异无统计学意义（t＝0.198， P＝0.256）；FPSA 水平分别为（1.18±0.91）μg／L、（2.32±1.20）μg／L，FPSA／TPSA 比值分别为0.12±0.08、0.24±0.23，两组差异均有统计学意义（t＝23.56，P＝0.020；t＝32.45，P＝0.006）。以FPSA／TPSA比值等于0.16为诊断阈值时，对PCa诊断的敏感度和特异度分别为84.4%和79.8%。结论血清TPSA水平随年龄而变化，应以各年龄段的95%位数作为医学决定水平，以提高其诊断PCa的特异性和准确性。对于TPSA水平处于“诊断灰区”的患者， FPSA／TPSA比值对PCa与BPH的鉴别诊断有较大临床价值。

Objective To evaluate the changes of serum total prostate specific antigen （TPSA） with age and its significance in differential diagnosis of prostate cancer （PCa） and prostatic hyperplasia （BPH）. Methods TPSA and free prostate specific antigen （FPSA） in 146 cases of PCa, 108 cases of BPH and 210 cases of healthy subjects were detected by electrochemiluminescence. Results There was a positive correlation between age and serum TPSA level （r=0.265, P〈0.01）. The levels of TPSA in PCa and BPH groups were （85.40 ±56.70） μg/L and （7.90 ±7.00） μg/L, and the difference was statistically significant （t=8.310, P= 0.001）; FPSA levels were （5.16±4.90） μg/L, （1.50±1.36） μg/L, and the difference was statistically significant （t= 3.152, P= 0.030）. In patients with TPSA levels ranging from 4.0 to 20.0 μg / L （＆quot;diagnostic gray zone＆quot;）, the levels of TPSA in PCa and BPH groups were （8.82±4.01）μg/L and （8.41±3.95）μg/L, and the difference had no statistical significance （t= 0.198, P= 0.256）; The levels of FPSA were （1.18 ±0.91） μg/L and （2.32±1.20） μg/L, the ratio of FPSA/TPSA were 0.12±0.08 and 0.24±0.23, and the differences were statistically significant （t= 23.56, P= 0.020; t= 32.45, P= 0.006）. When FPSA/TPSA ratio was 0.16, its sensitivity and specificity for PCa were 84.4%and 79.8%, respectively. Conclusions Serum TPSA levels vary with age, and 95 % of all age groups should be used as the medical criterion to improve the specificity and accuracy of PSA in diagnosing with PCa. The ratio of FPSA/TPSA has a significant clinical value in differential diagnosis of PCa and BPH in patients with TPSA in＆quot;diagnostic gray zone＆quot;.