前列腺活检对血清T-PSA F-PSA及F/T比值的影响

目的 :研究经直肠前列腺穿刺活检对血清总前列腺特异抗原 (T PSA)、游离前列腺特异抗原 (F PSA)及游离 /总前列腺特异抗原 (F/T)比值的影响。方法 :对 36例前列腺活检示良性病变的患者 ,分别于活检前及活检后 0 .5h、1周、30d检测T PSA、F PSA值 ,并计算F/T比值。结果 :活检前及活检后 0 .5h、1周、30d患者血清T PSA分别为 (11.76± 7.82 ) μg/L、(36 .90± 2 4 .76 ) μg/L、(2 4 .36± 16 .18) μg/L和 (12 .2 1± 6 .4 9) μg/L ;F PSA分别为 (2 .4 1± 0 .96 ) μg/L、(2 5 .14± 12 .5 6 ) μg/L、(4 .0 2± 1.90 ) μg/L和 (2 .6 1± 0 .87) μg/L ;F/T比值分别为 0 .2 1± 0 .0 6、0 .6 8± 0 .18、0 .15± 0 .0 4和 0 .2 2± 0 .0 5。与活检前相比 ,活检后 0 .5h、1周T PSA、F PSA值显著升高 (P <0 .0 1、P <0 .0 5 ) ;F/T比值活检后 0 .5h显著升高 (P <0 .0 1) ,活检后 1周时显著降低 (P <0 .0 5 ) ;活检后 30d时 ,以上指标与活检前相比 ,差异均无统计学意义 (均P >0 .0 5 )。结论 :前列腺穿刺活检 ,会导致血清T PSA、F PSA及F/T比值的显著升高 ,临床上要获得有意义的PSA的指标 ,最好在活检 30d后检测     

Inactive free : total prostate specific antigen ratios in ejaculate from men with suspected and known prostate cancer, compared with young control men

OBJECTIVE: To measure free : total prostate specific antigen (PSA) ratios in ejaculate from men with suspected and known prostate cancer, and in young control men, to determine if this ratio might be useful in discriminating benign from malignant prostatic conditions. Patients, subjects and methods Forty-seven men with prostate cancer (positive biopsies), 52 men with suspected prostate cancer but who had negative biopsies and 28 young men (< 30 years old) and with no family history of cancer, provided either a single ejaculate specimen (total 59) or multiple specimens (total 193) on subsequent occasions. Free and total PSA were measured using appropriate assays. All specimens were diluted in a PSA-negative female serum pool. RESULTS: The median free : total PSA ratios were 0.76-0.81 among the patient groups and control men, and there was no statistical difference between the groups. These data presumably only reflect the inactive component of free PSA, given that any alpha2-macroglobulin or alpha1-antichymotrypsin in the assay serum diluent was likely to have bound the active free PSA component in these samples. Similar results were obtained from those providing single and multiple samples, suggesting that a single specimen is sufficient to reflect the seminal plasma free : total PSA ratio over that period. There was no relationship between seminal plasma free : total PSA ratio and age for the controls or the positive biopsy group, although there was a negative relationship (i.e. a decline with age) that almost reached significance in those with negative biopsies (P = 0.058, R2 = 0.07). CONCLUSIONS: This is the first report of free : total PSA ratios in the ejaculate of men with suspected and known prostate cancer compared with young control men. Although no significant changes were detected in the free : total PSA ratios in ejaculate, these results may be confounded by differences in ratios with age, as is the case for serum PSA or different molecular forms of PSA. Indeed, these data suggest that a large proportion of free PSA in seminal plasma may be inactive. Further studies are needed to determine the potential utility of measuring free : total PSA, or other candidate markers, in ejaculate to better discriminate benign from malignant prostate disease.     

Influence of prostate volume and percent free prostate specific antigen on prostate cancer detection in men with a total prostate specific antigen of 2.6 to 10.0 ng/ml

PURPOSE: Percent free prostate specific antigen and prostate specific antigen density have been independently shown to increase the specificity of prostate cancer screening in men with prostate specific antigen levels between 4.1 and 10.0 ng/ml. Recent data suggest the total prostate specific antigen cutoff for performing a biopsy should be 2.6 ng/ml. We assessed the influence of percent free prostate specific antigen and prostate volume on cancer detection in men with a prostate specific antigen between 2.6 and 10.0 ng/ml. MATERIALS AND METHODS: From 1991 to 2005 all transrectal ultrasound guided prostate biopsies (5,587) for abnormal digital rectal examination and/or increased age specific prostate specific antigen were evaluated. A total of 1,072 patients with a prostate specific antigen between 2.6 and 10.0 ng/ml and any percent free prostate specific antigen were included in study. The cancer detection rate was calculated for each percent free prostate specific antigen/volume stratum. RESULTS: Prostate cancer was detected in 296 patients (27.6%). The mean age and prostate specific antigen of the patients with benign pathology and prostate cancer were similar. Mean percent free prostate specific antigen was 17.5% and 14.1% (p>0.05), and the mean volume was 62.0 and 46.0 cc (p=0.001), respectively. The strongest risk factors for a positive biopsy were percent free prostate specific antigen (odds ratio 0.004, p<0.001), volume (OR 0.977, p<0.001) and digital rectal examination (OR 1.765, p=0.007), but not total prostate specific antigen (p=0.303). When stratified by volume and percent free prostate specific antigen, distinct risk groups were identified. The probability of detecting cancer inversely correlated with prostate volume and percent free prostate specific antigen. CONCLUSIONS: In men with prostate specific antigen levels between 2.6 and 10.0 ng/ml, the probability of detecting cancer was inversely proportional to prostate volume and percent free prostate specific antigen. This table may assist in predicting patient risk for harboring prostate cancer.     

Percent free prostate specific antigen and cancer detection in black and white men with total prostate specific antigen 2.5 to 9.9 ng./ml

PURPOSE: The ratio of free-to-total prostate specific antigen (PSA), or percent free PSA, is a useful adjunct to total PSA for estimating the risk of prostate cancer when total PSA is 2.5 to 9.9 ng./ml. Relationships between cancer detection and total PSA are influenced by race but to our knowledge relationships between cancer detection and percent free PSA have not been studied. MATERIALS AND METHODS: A total of 222 black and 298 white consecutive and evaluable men with total PSA 2.5 to 9.9 ng./ml. underwent prostate biopsy for suspected cancer at a Veterans Affairs Medical Center. Clinical measurements included digital rectal examination, total and free serum PSA, prostate volume, PSA density and Gleason score of malignant biopsy specimens. RESULTS: Median percent free PSA was 14.1 (range 3.6 to 49.2) in 201 men with prostate cancer and 21.9 (range 5.7 to 83.3) in 319 without detectable cancer (p <0.0001). Significant racial differences in demographic characteristics and clinical measurements were limited to total PSA, which was higher in black men (p = 0.03). Cancer was detected in 156 black (47%) and 206 white (33%) men (p = 0.001). Areas under receiver operating characteristics curves for percent free PSA and total PSA were 0.66 and 0.58, respectively, for black men (p = 0.15), and 0.76 and 0.58, respectively, for white men (p <0.00001). Percent free PSA was 35.2 in black men and 29.2 in white men, and specificity was 9.1% and 28.7%, respectively, when sensitivity for percent free PSA was set at 95%. Of 156 black and 206 white men with percent free PSA less than 25, 83 (53%) and 85 (41%), respectively, had detectable cancer (p = 0.03). Of 66 black and 92 white men with percent free PSA 25 or greater 21 (32%) and 12 (13%), respectively, had detectable cancer (p = 0.005). CONCLUSIONS: Our study demonstrates racial differences in relationships between percent free PSA and cancer detection in men with suspected prostatic carcinoma and total PSA 2.5 to 9.9 ng./ml. Clinical application of the commonly used percent free PSA cutoff of less than 25 to determine the advisability of prostate biopsy may lead to under diagnosis of early stage prostate cancer in black men, who are at greater risk of morbidity and mortality from disease than white men.     

Prostate-specific antigen and prostate gland size in men receiving exogenous testosterone for male contraception

Steroid regimens containing androgens are being evaluated currently as hormonal contraceptives for men. The possible non-reproductive effects of such treatment were assessed during an efficacy trial using a prototype regime of 200 mg testosterone enanthate i.m. weekly. Prostatic function and size were monitored by regular rectal examination, blood levels of prostate-specific androgen (PSA) were measured in 30 men and prostatic size was measured by trans-rectal ultrasound imaging in a representative subgroup of five subjects for 12 months and for a further 6 months after discontinuation. Despite the sustained rise in serum levels of testosterone, oestradiol and dihydrotestosterone during treatment, there was no detectable increase in prostatic size on rectal examination or any significant change in blood concentrations of PSA. A small but significant increase (14.3 ± 2.0%) in maximal prostate transverse area was observed in four men while the remaining one showed no change. Our preliminary data demonstrate the feasibility and importance of monitoring prostatic function in the development of androgen-containing male hormonal contraceptives.     

The association between total prostate specific antigen concentration and prostate specific antigen velocity

PURPOSE: It has been previously demonstrated that a prostate specific antigen velocity greater than 2 ng/ml per year is associated with reduced cancer specific survival following radical prostatectomy or external beam radiation. However, men with different initial prostate specific antigen levels may be more or less likely to reach this prostate specific antigen velocity threshold. Because prostate specific antigen and prostate specific antigen velocity contain much of the same predictive information, our objective was to further examine the relationship between them. MATERIALS AND METHODS: From a large prostate cancer screening study, serial prostate specific antigen measurements were available for 13,276 men, including 1,851 with a negative digital rectal examination who underwent biopsy and 894 who were diagnosed with prostate cancer. Prostate specific antigen velocity was calculated using simple linear regression of the prostate specific antigen values from the year before diagnosis. ANOVA and the Kruskal-Wallis test were used to compare the mean and median prostate specific antigen velocity of men in different total prostate specific antigen ranges. In addition, chi-square analysis was used to compare the number of men in each total prostate specific antigen range who presented with high risk prostate specific antigen velocity greater than 2 ng/ml per year. RESULTS: In the total prostate specific antigen ranges of 2.5 ng/ml or less, 2.6 to 4.0, 4.1 to 10.0 and more than 10.0 ng/ml, the proportion of screened men with a prostate specific antigen velocity of more than 2 ng/ml per year was 1%, 14%, 31% and 74%, respectively (p <0.0001). Mean and median prostate specific antigen velocity were also significantly higher as the total prostate specific antigen level increased. CONCLUSIONS: Prostate specific antigen velocity varies directly with total prostate specific antigen. Men with high initial prostate specific antigen levels are significantly more likely to present with a prostate specific antigen velocity of more than 2 ng/ml per year that is more frequently associated with prostate cancer specific mortality.     

The effect of colonoscopy on serum prostate specific antigen levels.

OBJECTIVE: To evaluate, in a prospective trial, the effect of colonoscopy on serum prostate specific antigen (PSA) levels (which are known to increase after cystoscopy and prostatic needle biopsy) in men aged 50-70 years, as they commonly undergo colonoscopy and PSA screening together. SUBJECTS AND METHODS: Twenty-four consecutive men (mean age 61 years, range 37-78) were enrolled in the study. All subjects had their serum PSA measured 24-72 h before undergoing colonoscopy. Further values were obtained 24 h, 7 and 30 days after the procedure. The values before and after colonoscopy were compared to evaluate the effect of colonoscopy on serum PSA levels. RESULTS: Of 24 patients, seven (35%) had insignificant increases at 24 h after colonoscopy; 12 (50%) patients had an insignificant increase in PSA level 30 days after the procedure. None of the 24 patients had a significant increase after colonoscopy when compared with baseline values. CONCLUSION: Flexible colonoscopy does not adversely affect serum PSA levels. Although individuals may have a 30% daily fluctuation in serum values, this study detected no significant change in serum PSA levels after prolonged transrectal prostatic manipulation with a colonoscope.     

血清PSA、f-PSAR与前列腺重量相关性研究

目的：探讨前列腺增生症（ＢＰＨ）人群中前列腺重量（ＰＷ）与血清前列划抗原（ＰＳＡ）、血清液离前腺特异抗原百分率（ｆ－ＰＳＡＲ）的相关性,方法：术前测定１４６例ＢＰＨ患者血清ＰＳＡ〈其中５１例测定了血清游离前列腺特异抗原值,对血清ＰＳＡ〉１０μｇ／Ｌ患者行前列腺穿刺活检以排除前列腺癌,术后对前列腺手术标本进行称重,并按〈２５ｇ,２５￣５０ｇ、５１￣７５ｇ、〉７５ｇ分为４组,均经病理证实为ＢＰＨ,对忾     

Intra-individual variation of serum prostate specific antigen levels in men with benign prostate biopsies

OBJECTIVE: To determine the intra-individual (physiological) variation of prostate-specific antigen (PSA) measurements in men after a benign prostatic biopsy. PATIENTS AND METHODS: Sixty-four men were prospectively assessed, all of whom had a benign prostatic biopsy within the preceding 13 months. The degree of intra-individual variability was established by calculating the coefficient of variation on four PSA levels obtained from each patient weekly over a month. RESULTS: Six patients were subsequently diagnosed with prostate cancer and their data are presented separately. In the remaining 58 patients the median (range) individual mean PSA value was 6.3 (0.5-34.1) ng/mL. The median (range) coefficient of variation within the group was 9.5 (2.4-76.1)%. There was a clear linear relationship between mean PSA level and the standard deviation. CONCLUSION: In 48 of the 63 patients analysed, the coefficient of variation for serum PSA values in the group as a whole was greater than the variation claimed for the assay technique. The significance of the linear relationship between PSA and the standard deviation is discussed, with particular reference to those men who had a benign prostate biopsy.     

Prostate specific antigen velocity threshold for predicting prostate cancer in young men

PURPOSE: Longitudinal changes in prostate specific antigen are increasingly used to guide the recommendation for biopsy. Prostate specific antigen velocity 0.75 ng/ml yearly has been proposed to distinguish prostate cancer from benign prostate conditions. However, this threshold might be too high in young men with lower total prostate specific antigen. MATERIALS AND METHODS: In a large prostate cancer screening study 6,844 men were 60 years or younger at study entry and prostate specific antigen velocity calculation was possible. Of these men 346 (5%) were subsequently diagnosed with prostate cancer and various prostate specific antigen velocity thresholds were examined for prediction of prostate cancer risk. Multivariate analysis was performed to determine whether prostate specific antigen velocity is an independent predictor of prostate cancer in men younger than 60 years. RESULTS: Median prostate specific antigen velocity was significantly higher in men who were later diagnosed with prostate cancer than in those who were not (0.840 vs 0.094 ng/ml yearly, p<0.0001). On multivariate analysis prostate specific antigen velocity greater than 0.4 ng/ml yearly was more predictive of prostate cancer than age, total prostate specific antigen, family history or race. Multivariate analysis in the subgroup of men with total prostate specific antigen less than 2.5 ng/ml had similar results. Overall a cutoff of 0.4 ng/ml yearly was associated with 67.3% sensitivity, 81.2% specificity, 16% positive predictive value and 98% negative predictive value for prostate cancer detection in young men. CONCLUSIONS: The traditional prostate specific antigen velocity threshold of 0.75 ng/ml yearly is too high for men younger than 60 years and it misses 48% of prostate cancers. Young men with prostate specific antigen velocity greater than 0.4 ng/ml yearly are at significantly greater risk for prostate cancer and close followup is warranted.     

Probability of prostate cancer at various levels of per cent free prostate specific antigen in Japanese men with total PSA of 4.1-10.0 ng/ml

Estimates for the likelihood of prostate cancer at different levels of per cent free prostate specific antigen (PSA) were derived from experience with consecutive Japanese male patients with intermediate total PSA values who underwent ultrasound-guided biopsies and/or transurethral resection of the prostate. Receiver operating characteristic (ROC) curve analysis showed that in patients with a total PSA of 4.1-10.0 ng/ml, per cent free PSA identified those with prostate cancer better than did total PSA; per cent free PSA also proved superior in the subgroup whose glands appeared benign on palpation. The probabilities of prostate cancer at per cent free PSA values of 10-15, >15-20, >20-26 and >26% were 58.3, 40.8, 25.3, 14.3 and 7.6%, respectively, when analyzed without regard to findings on palpation. In patients with palpably benign glands, the corresponding values were 55.3, 35.4, 19.6, 9.7, and 4.6%, respectively. These probabilities are lower than those reported in Western countries, probably reflecting both different patterns of practice and racial differences. Race-specific assessment is recommended before applying a clinical test.     

游离前列腺特异抗原百分比/前列腺特异抗原密度在前列腺癌诊断中的应用

目的探讨游离前列腺特异抗原百分比（FPSA／TPSA值）／前列腺特异抗原密度[（F／T）／PSAD值]在前列腺癌诊断中的意义。方法回顾分析204例行经直肠超声引导前列腺穿刺活检患者的诊断资料,其中前列腺癌90例、良性前列腺增生114例,分析总PSA（TPSA）、FPSA／TPSA值、PSAD、（F／T）／PSAD值等指标在判断前列腺癌的敏感性为90％时的截点及相应的特异性。结果不同血清PSA水平（〈4．0,4．0～,10．1～和〉20．0μg／L）的前列腺癌患者的（F／T）／PSAD值与良性前列腺增生患者比较,差异有统计学意义（P〈0．05）;前列腺癌患者的（F／T）／PSAD值低于良性前列腺增生患者;（F／T）／PSAD值比FPSA／TPSA值和PSAD更有助于提高诊断特异性,在敏感性为90％左右的前提下,FPSA／TPSA值的特异性为31．6％,PSAD的特异性为45．6％,（F／T）／PSAD值的特异性为64．0％;PSA水平不同,取的（F／T）／PSAD值截点也不同：PSA〈4．0μg/L时截点为2．5,PSA为4．0～20．0μg／L时截点为0．8;PSA〉20．0μg／L时截点为0．5。结论应用（F／T）／PSAD值能够在保持较高敏感性的前提下,显著提高前列腺癌诊断的特异性。     

(I) Re: prostate specific antigen velocity in men with total prostate specific antigen less than 4 ng/ml

This study analyses the prostate-specific antigen (PSA) determinations of 11,709 men with two or more PSA measurements within approximately 12 mo, an initial PSA of <4 ng/ml, and using biopsy indications of PSA > or 2.5 ng/ml or > or =4.0 ng/ml. The authors found that PSA velocity (PSAV) thresholds in the range of 0.4 ng/ml/yr should be used to help guide the need for biopsy in men with a total PSA level <4 ng/ml. Receiver operating characteristic (ROC) analysis showed that the area under the curve (AUC) was 0.68 for PSAV and 0.87 when total PSA was included in addition to PSAV.     

Age-specific reference levels of serum prostate-specific antigen and prostate volume in healthy Arab men

OBJECTIVE; To determine age-specific reference ranges for serum prostate-specific antigen (PSA) concentration and prostate volumes in a population of healthy Arab men. SUBJECTS AND METHODS: Blood samples were taken from 396 healthy Arab men (from Kuwait and Oman) aged 15-79 years and from across the social spectrum. Men aged >40 years had a digital rectal examination and transrectal ultrasonography of the prostate to determine prostate volume. The serum PSA level was measured using commercial kits, and age-specific ranges for PSA levels and prostate volume determined. RESULTS: The serum PSA ranges (ng/mL) for each age range in Arab men were: 40-49 years, 0-0.9; 60-69, 0-2.7; 70-79, 0-5.5 ng/mL; the respective prostate volumes were 8-22, 9-30 and 10-33 mL. The serum PSA level and prostate volume correlated with age (P < 0.001). Arab men had lower serum PSA levels and prostate volumes than those reported for Caucasians, but similar to those reported for Asians (Japanese and Chinese). CONCLUSION: These results indicate that Arab men have lower PSA levels and prostate volumes than Caucasians. The levels are slightly lower than those reported in the Japanese and, as in the Japanese, low PSA levels and small prostate volumes might be related to the low incidence of clinical prostate cancer in Arab men.     

The effect of microsurgical varicocelectomy on serum follicle stimulating hormone, testosterone and free testosterone levels in infertile men with varicocele

OBJECTIVES: To analyse the effects of varicocelectomy on serum follicle-stimulating hormone (FSH), testosterone and free testosterone levels, and to investigate the interrelationships between seminal and hormonal variables. PATIENTS AND METHODS: The records were retrospectively evaluated for 78 infertile patients who underwent microsurgical inguinal varicocelectomy, with documented serum FSH, testosterone, free testosterone levels, sperm concentration and sperm motility before and after surgery. Left and bilateral varicoceles were detected in 40 and 38 patients, respectively. In addition, serum hormonal values of 10 fertile men in whom physical examinations and Doppler ultrasonography revealed no evidence of varicocele were recorded and used as a control group. RESULTS: The mean (sd) serum FSH levels of all patients decreased from 15.21 (3.34) before surgery to 10.82 (2.93) mIU/mL afterward (P=0.01), and serum testosterone levels increased from 5.63 (1.40) to 8.37 (2.2) ng/mL (P=0.01), whereas free testosterone levels increased from 23.13 (3.19) to 32.83 (4.37) pg/mL (P<0.001). In contrast to the significant difference in sperm motility before and after surgery of all patients (P<0.01), the difference in sperm count was insignificant (P>0.05). Thirty-six patients with high serum FSH levels before surgery had significantly lower levels afterward (P=0.001). In this group, the sperm concentration and motility also increased, from 17.66 (4.35) to 20.76 (4.37) million/mL (P=0.05) and from 30.9 (4.4)% to 37.5 (4.34)%, respectively (P=0.01). In the remaining 42 patients who had normal preoperative serum FSH levels, there was a slight decrease after surgery (P=0.02). Their sperm concentration increased slightly (P=0. 04), and motility also increased (P=0.001). Sixty patients had a significantly higher testosterone level after surgery; in this group the sperm concentration and motility increased (P=0.01). CONCLUSION: Varicocelectomy promotes Sertoli and Leydig cell function. The significant increase in serum free testosterone level results in a significant improvement in sperm concentration and motility.