Relationship among age, prostate-specific antigen, and prostate volume in men with lower urinary tract symptoms (LUTS) and in different groups of men with and without benign and malignant prostate diseases

Relationship between serum prostate-specific antigen and transrectal prostate sonographic findings in asymptomatic Ugandan males

Background

Prostate disorders are among the leading causes of morbidity and mortality in men above the age of 40 years globally. Serum prostate-specific antigen (PSA) levels may be used to screen men at risk of prostate cancer and determine choice of medical treatment in benign prostatic hyperplasia (BPH) and evaluation of patients with prostatitis, while prostate sonography determines prostate volume (PV) and detects nodules. BPH may exhibit distinct hypoechoic, isoechoic, or hyperechoic nodules in the transition zone, whereas hypoechoic nodules in the peripheral zone are diagnostic for prostate cancer in over 50% of cases. In this study, we aimed at determining the relationship between serum PSA levels and transrectal prostate sonographic findings among asymptomatic Ugandan males.

Methods

Ugandan males above 30 years of age or older without lower urinary tract symptoms were cross-sectionally enrolled into the study. Serum PSA determination and transrectal ultrasound were performed. Association between PSA levels and PV was assessed using Spearman’s correlation coefficients (ρ).

Results

A total of 277 men were studied. The median serum PSA level was 1 (95% CI: 1–2). Most (n = 217, 78.3%) participants had serum PSA levels ≤ 4 ng/ml. The median sonographic PV was 26 (95% CI: 26–29) mls. One hundred and fifty-five (56.0%) participants had PV between 25 and 50 mls. Both PSA levels and PV progressively increased with age from 0.9 ng/ml and 22 mls in the 30–39 year age group to 7 ng/ml and 38 mls in the 60–69 year age group, respectively. PSA levels weakly correlated with PV (ρ = 0.27) (p < 0.0001). One hundred and thirty (47%) participants had prostatic nodules. Of these, 100 (77%) had features of benign nodules and 23% had suspicious nodules for prostate cancer. The median (range) serum PSA level in those with nodules was 2.0 (0.1–16.0) ng/ml and for those without nodules was 1.1 (0.1–8.0) ng/ml (p < 0.0001).

Conclusions

Serum PSA has a weak direct correlation with PV and not a reliable marker for the prediction of presence or absence of prostatic nodules in asymptomatic adult males.

Effect of prostate volume on f/tPSA value: A cross-sectional study

Previous studies have suggested that there is a positive correlation between prostate-specific antigen (PSA) levels and prostate volume (PV). A better understanding of the possible influence of PV on a ratio of free to total PSA (f/tPSA) may improve the diagnostic value of the prostate disease. The study group consisted of 342 men with lower urinary tract symptoms (LUTS). All patients underwent urinary tract ultrasonography and had tests carried out on PSA, serum glucose, total cholesterol, triglyceride, HDL, LDL and blood pressure. Univariate and multivariate analyses were used to assess the associations between prostate volume and f/tPSA value. We found no obvious relationship between prostate volume and f/tPSA value when PSA >10 ng/ml but did observe a positive correlation when 4 ng/ml < PSA ＜ 10 ng/ml (hazard ratio [HR]: 0.0012; 95% confidence interval [CI]: 0.0009-0.0248). With increasing prostate volume, multivariate analysis showed an obvious increase in f/tPSA value (HR: 0.0011; 95% CI: 0.0007-0.0015) (p ≤ .0001). We confirmed that prostate volume could affect the f/tPSA levels in serum. There was an obvious positive correlation between prostate volume and f/tPSA level when PSA levels were between 4 and 10ng/dl. There was no significant correlation between prostate volume and f/tPSA value when PSA >10 ng/ml.

Does prostate-specific antigen (PSA) mass or free PSA mass improve the accuracy of predicting total prostate volume in relation to obesity in men with biopsy-proven benign prostatic hyperplasia?

We evaluated whether the prostate-specific antigen (PSA) mass or free PSA (fPSA) mass ( i.e ., absolute amount of total circulating PSA or fPSA protein, respectively), versus serum PSA or fPSA concentration, improves the accuracy of predicting the total prostate volume (TPV) in relation to obesity. Among men whose multicore (≥12) transrectal prostate biopsy was negative, 586 who had a PSA of ≤10 ng ml -1 and underwent the fPSA test prior to biopsy were enrolled. The PSA mass or fPSA mass (μ g) was calculated by multiplying the serum level by plasma volume. At each TPV cut-off point (30 ml, 40 ml, and 50 ml), the areas under the receiver operating characteristics curve (AUCs) of each variable were compared in obesity-based subgroups. AUCs of fPSA and fPSA mass for predicting TPV were significantly larger than those for PSA and PSA mass by 8.7%-12.1% at all cut-off points. Subgroup analyses based on obesity showed that, although PSA mass and fPSA mass enhanced accuracy by 4% ( P = 0.031) and 1.8% ( P = 0.003), respectively, for determining TPVs of ≥30 ml and ≥50 ml in obese and overweight men, they did not improve the accuracy in most other combinations of the degrees of obesity with TPV cut-off points. Thus, compared with serum PSA or fPSA, the absolute amount of PSA or fPSA protein mass improved the accuracy of predicting TPV in obese men very minimally and only for certain TPV cut-off points. Hence, these indicators may not provide clinically meaningful improvement in predicting TPV in obese men.

Serum prostate-specific antigen as a predictor of prostate volume and lower urinary tract symptoms in a community-based cohort: a large-scale Korean screening study

The aim of this study is to assess the ability of serum prostate-specific antigen (PSA) to predict prostate volume (PV) and lower urinary tract symptoms (LUTS) represented by the international prostate symptom score (IPSS). From January 2001 to December 2011, data were collected from men who first enrolled in the Korean Prostate Health Council Screening Program. Patients with a serum PSA level of >10 ng ml(-1) or age <40 years were excluded. Accordingly, a total of 34 857 men were included in our study, and serum PSA, PV and the IPSS were estimated in all patients. Linear and age-adjusted multivariate logistic analyses were used to assess the potential association between PSA and PV or IPSS. The predictive value of PSA for estimating PV and IPSS was assessed based on the receiver operating characteristics-derived area under the curve (AUC). The mean PV was 29.9 ml, mean PSA level was 1.49 ng ml(-1) and mean IPSS was 15.4. A significant relationship was shown between PSA and PV, and the IPSS and PSA were also significantly correlated after adjusting by age. The AUCs of PSA for predicting PV >20 ml, >25 ml and >35 ml were 0.722, 0.728 and 0.779, respectively. The AUCs of PSA for predicting IPSS >7, >13 and >19 were 0.548, 0.536 and 0.537, respectively. Serum PSA was a strong predictor of PV in a community-based cohort in a large-scale screening study. Although PSA was also significantly correlated with IPSS, predictive values of PSA for IPSS above the cutoff levels were not excellent. Further investigations are required to elucidate the exact interactions between PSA and LUTS and between PSA and PV in prospective controlled studies. Such studies may suggest how PSA can be used to clinically predict PV and the IPSS.

Relationships between total/free prostate-specific antigen and prostate volume in Chinese men with biopsy-proven benign prostatic hyperplasia

OBJECTIVE

This study investigated relationships between total prostate-specific antigen (tPSA), free prostate-specific antigen (fPSA), and prostate volume (PV) in Chinese men with biopsy-proven BPH, and analyzed whether fPSA performed better than tPSA at estimating thresholds of PV.

MATERIALS AND METHODS

From 2003 to 2008, a total of 286 patients with a PSA less than 10 ng/ml and biopsy proven benign prostatic hyperplasia were included in this study. The relationships between age, PV, tPSA, and fPSA were analyzed using the Pearson correlation coefficient (r). Receiver-operating characteristic (ROC) curves were constructed to evaluate and compare the ability of serum tPSA and fPSA to estimate thresholds of PV in men with biopsy-proven BPH.

RESULTS

Among relationships between tPSA, fPSA, age, and PV, the highest correlation was found between fPSA and PV (r = 0.456, P < 0.001); the correlation coefficient was much lower between tPSA and PV (r = 0.278, P < 0.001). The ROC curves revealed that the performance of fPSA at predicting threshold prostate sizes (30, 40, and 50 ml) showed areas under the curve (AUC) ranging from 0.72 to 0.75, denoting better discrimination of PV than that achieved by use of tPSA.

CONCLUSION

Although tPSA significantly correlated with PV in Chinese men with biopsy-proven BPH, the correlation between fPSA and PV was much stronger, and fPSA performed significantly better than tPSA at predicting thresholds of PV. fPSA may be used to estimate PV and could be a useful tool in making therapeutic decisions in Chinese men with BPH.

Relationship between serum prostate-specific antigen and prostate volume in Korean men with benign prostatic hyperplasia: a multicentre study

OBJECTIVES

To evaluate the relationship between prostate specific antigen (PSA) and prostate volume (PV) in Korean men, as PV is a key predictor of both disease progression and response to medical therapy in patients with benign prostatic hyperplasia (BPH), and PSA has been suggested as a proxy marker to estimate the total PV, mainly in Caucasians.

PATIENTS AND METHODS

From 1999 to 2004, men aged 50-79 years with lower urinary tract symptoms (LUTS) and BPH were enrolled into this multicentre study. The analyses included 5716 patients presenting to 11 medical centres with LUTS (International Prostate Symptom Score >8, peak urinary flow rate <15 mL/s); they had a mean age of 64.3 years, mean baseline PV of 36.9 mL, and mean baseline PSA level of 2.2 ng/mL. Men with a baseline PSA of >10 ng/mL were excluded, to reduce the likelihood of including occult prostate cancer. A biopsy was taken in those with suspicious findings on a digital rectal examination or serum PSA level of >4 ng/mL, to exclude prostate cancer. Receiver operating characteristic (ROC) curves were constructed to evaluate the ability of serum PSA to predict threshold PV in men with BPH.

RESULTS

The PV and serum PSA level had an age-dependent log-linear relationship, the strength of which increased with age. The ROC curve analysis showed that PSA had good predictive value for various prostate volume thresholds (30, 40 and 50 mL).

CONCLUSIONS

The PSA-PV relationship in Korean men is similar to that in Caucasians, but Korean men have a slightly lower PSA level and a smaller PV than Caucasians. The approximate age-specific criteria for detecting Korean men with a PV of >40 mL were a PSA level of >1.3 ng/mL, >1.7 ng/mL and >2.0 ng/mL for men with BPH in their sixth, seventh and eighth decade, respectively.

Saw palmetto is an indirectly acting sympathomimetic in the rat-isolated prostate gland

BACKGROUND

To investigate whether saw palmetto that inhibits alpha1-adrenoceptor binding in vitro affects contractility of the rat prostate gland.

METHODS

The effects of a commercially available saw palmetto extract were examined on the contractility of rat-isolated prostate glands. The extract was tested in the presence and absence of phentolamine, prazosin, yohimbine, propranolol, hexamethonium, cocaine, desipramine, nifedipine, guanethidine, atropine, and alpha,beta-methylene ATP to evaluate the mechanism of action. Isolated preparations of rat vas deferens and bladder were used for comparison.

RESULTS

Unexpectedly, saw palmetto extract caused contractions of the rat prostate gland that could be attenuated by prazosin, phentolamine, nifedipine, guanethidine, cocaine, and desipramine but not by any of the other pharmacological tools. Similar contractile effects were observed in rat-isolated vas deferens preparations but not in rat-isolated bladder preparations.

CONCLUSIONS

In the rat prostate gland, saw palmetto extract causes indirect alpha1-adrenoceptor-mediated contractions via the release of noradrenaline from sympathetic neurons.

Prostate-Specific Antigen as an Estimator of Prostate Volume in the Management of Patients with Symptomatic Benign Prostatic Hyperplasia

OBJECTIVES

To assess the ability of serum prostate specific antigen (PSA) to estimate prostate volume (PV) to aid in the management of patients with benign prostatic hyperplasia (BPH).

METHODS

From 1989 to 2002, data were collected from 2264 patients complaining of lower urinary tract symptoms (LUTS) who visited the Department of Urology of the University Medical Centre Nijmegen, The Netherlands. Baseline PV and serum PSA was determined using standard techniques. All patients who had a baseline PV < or =200 ml, as well as a baseline serum PSA 0-10 ng/ml, were included. Patients with a history of prostate surgery, prostate cancer and conditions other than BPH at baseline were excluded. A log-transformed linear regression model was used to estimate PV. Receiver-operating characteristic (ROC) curves were constructed to evaluate the ability of serum PSA to estimate threshold PVs in men with BPH, and to select the optimal serum PSA cut-off values.

RESULTS

The analyses included 1859 patients with a mean age of 63.5 years, mean baseline PV 43.9 ml, and mean baseline PSA value 3.1 ng/ml. PV as well as serum PSA increases with age. Linear regression analyses showed that PV and serum PSA have an age-dependent log-linear relationship, where 42% of the variance of PV can be explained by PSA and age. ROC's area under the curves (AUC) reveal that PSA has a good predictive value for assessing 'prostate enlargement', with AUC around 82% in the overall age groups irrespective of the PV cut-off values. Optimal serum PSA cut-off values for the overall study population irrespective of age are 2.0 ng/ml to detect PV >30 ml and 2.5 ng/ml to detect PV >40 ml.

CONCLUSIONS

This study suggests that serum PSA can estimate prostate enlargement sufficiently accurately to be useful for therapeutic, especially medical, management. It is well accepted that the outcome of pharmacotherapy for BPH depends on baseline PV. Therefore, in the absence of reliable direct measurement of PV, serum PSA determination may be used to optimise patient management.

Benign prostatic hyperplasia

In both ageing men and women, there is an increasing incidence of lower urinary tract symptoms (LUTS) which are increasing. These infections have many possible causes, including smooth muscle dysfunction, neurological factors and benign prostatic hyperplasia. Up to 15% to 25% of men aged 50-65 years have LUTS of sufficient severity to interfere with their quality of life. Although benign prostatic hyperplasia is an important cause of these symptoms, and can have serious consequences, clinicians should be aware of these other causes so that the appropriate diagnosis is made before invasive treatments are started. New medical treatments, including alpha-adrenergic blocking agents and 5 alpha-reductase inhibitors mean that many men without complications such as infection, bleeding, or chronic retention, and with mild to moderate symptoms, should be managed in primary care. Combined local protocols between primary and secondary care will help to establish which men with persistent symptoms or complications need referral for a urological opinion to determine the need for further investigation and more invasive forms of management. We review the pathophysiology of the disease, and current approaches to investigation and management of this common problem.

Distribution of inflammation, pre-malignant lesions, incidental carcinoma in histologically confirmed benign prostatic hyperplasia: a retrospective analysis

OBJECTIVES

We analyze our experience on BPH through 20 years of histopathological examinations performed by the same pathologist.

METHODS

We retrospectively reviewed all histopathological examinations performed from January 1979 to December 1998 in patients undergoing surgery in our urological clinic who were diagnosed with BPH. We limited our evaluation to the following variables in each BPH case analyzed: inflammatory aspects associated with BPH, presence of focal acinar atrophy, atypical adenomatous hyperplasia (AAH), prostatic intraepithelial neoplasia (PIN), incidental prostate carcinoma (IC). These histological variables were analyzed according to some clinical parameters such as age, prostate volume and serum PSA.

RESULTS

The study population was comprised of 3942 cases with histological diagnosis of BPH. The mean patient age was 68.85+/-7.67 years. In particular, inflammatory aspects were associated with BPH in a high percentage of cases (43.1% =1700 cases), predominantly as chronic inflammation. Observation of focal acinar atrophy significantly increased according to patient decade of age (p=0.027). There was a significant trend to increase with age decades (p=0.036) for high grade PIN. A significant difference was found in IC (T1a, T1b) distribution in the different decades of age and especially in regards to both T1a and T1b tumors, there was a trend to increase with patient age (p=0.020 and p=0.025, respectively). On the contrary, the distribution of inflammatory aspects (p<0.001) and AAH (p=0.003) significantly varied according to prostate volume, and particularly in regards to chronic inflammation, there was a trend to increase depending on the prostate volume (p=0.002). Only the presence of T1b tumor but not of the other histological parameters associated to BPH, was able to significantly influence serum PSA.

CONCLUSION

In our analysis different histological variables associated to BPH are differently influenced by the age of patients and prostate volume, and they differently influence serum PSA levels.

Prostate-specific antigen, prostate volume and transition zone volume in Japanese patients with histologically proven benign prostatic hyperplasia

The relationship among age, prostate-specific antigen (PSA) level and prostate volume in Japanese patients with lower urinary tract symptoms (LUTS) and histologically proven benign prostatic hyperplasia (BPH) was examined in order to assess the utility of PSA as a predictor of prostate volume. Two hundred eighteen patients with LUTS were confirmed to have BPH by histological examination for the reason of elevated PSA and/or abnormal digital rectal examination finding. Correlation among PSA, prostate volume and transition zone volume were analyzed in patients classified into age-stratified groups. Prostate volume increased with age. Mean serum PSA increased with age, and the correlation of PSA and prostate volume was determined to be statistically significant in each cohort of age. A correlation coefficient ranged from 0.315 to 0.439. In patients with LUTS and clinical BPH, serum PSA increased with age and was related to prostate volume. PSA might be useful for therapeutic decision making for patients with symptomatic BPH.

Relationship of prostate-specific antigen and prostate volume in patients with biopsy proven benign prostatic hyperplasia

BACKGROUND

Emerging data suggest a direct correlation between prostate-specific antigen (PSA) and prostate volume in patients with lower urinary tract symptoms (LUTS) and clinical evidence of benign prostatic hyperplasia (BPH). We attempt to confirm that a similar correlation exists between PSA and prostate volume in patients with biopsy-proven BPH.

METHODS

Over a 5 year period, 2,270 patients were confirmed to have BPH as the only histological diagnosis after evaluation with serum PSA, trans-rectal ultrasound (TRUS) biopsy, and prostate volume measurement. PSA and prostate volume were statistically analyzed by age-stratified cohorts, including multiple regression analysis and assessment of correlation using the Pearson correlation coefficient (r).

RESULTS

Mean PSA and prostate volume increased with each advancing cohort of age, and the correlation of PSA and prostate volume was determined to be statistically significant (P < 0.001) in each cohort with a correlation coefficient ranging from 0.33 to 0.41.

CONCLUSIONS

We confirm that the relationship between PSA and prostate volume in a large series of patients with biopsy-proven BPH provides a comparable correlation to data for patients with LUTS and clinical BPH. As such, PSA represents a valuable approximation of prostate volume, and may prove to be clinically useful in the management of patients with BPH.

Prostate specific antigen and benign prostatic hyperplasia

Benign prostatic hyperplasia is a common condition in males over 50 years, but prostate cancer can develop in the same population. Prostate specific antigen, the best marker for prostate cancer, is also produced by benign epithelial cells, and there is an overlapping phenomenon between both conditions. The better we understand the relationships between benign prostatic hyperplasia and prostate specific antigen, the higher will be the discrimination power of prostate specific antigen measurement as a marker for prostate cancer. Our scope includes a review of the latest published material to date on this subject.

Serum prostate-specific antigen as a predictor of prostate volume in men with benign prostatic hyperplasia

OBJECTIVES

To assess the utility of prostate-specific antigen (PSA) as a predictor of prostate volume by characterizing the relationship between prostate volume and serum PSA in men with symptomatic benign prostatic hyperplasia (BPH) and no evidence of prostate cancer, stratified by decade of life.

METHODS

Placebo-controlled multicenter trials in patients with BPH and a safety study in normal young men provided baseline measurements of serum PSA and prostate volume. The analyses included patients with a baseline prostate volume measured by either transrectal ultrasound (TRUS) or magnetic resonance imaging and baseline serum PSA. A common central laboratory was used for all but one of the individual studies; both laboratories used the Hybritech method. Patients 80 years of age or older were excluded. Patients with a baseline serum PSA greater than 10 ng/mL were excluded to reduce the likelihood of including occult prostate cancer cases. The patients in the BPH trials were screened at baseline by digital rectal examination (DRE) and serum PSA. Those with suspicious findings underwent TRUS-guided biopsy; only patients with negative biopsies are included in these analyses.

RESULTS

The analyses included 4627 patients, 4448 from the BPH trials and 179 from the safety study. The men in the BPH trials were older (mean age+SE, 63.7+0.10 years) than the men in the safety study (mean age + SE, 30.8+/-0.43), had larger prostates (mean volume+/-SE, 43.7+/-0.38 mL versus 26.3+/-0.49 mL in the safety study), and had higher serum PSA values (mean+/-SE, 2.6+/-0.03 ng/mL versus 0.7+/-0.39 ng/mL in the safety study). The relationship between prostate volume and serum PSA was evaluated using only the BPH trial data. Prostate volume and serum PSA have an age-dependent log-linear relationship (ie, their logarithms are linearly related, and the parameters of the relationship depend on age). Older men tend to have a steeper rate of increase in prostate volume with increasing serum PSA (P < 0.00 for differences between slopes), and there was a slight tendency for PSA density to increase with age. Receiver operating characteristic (ROC) curves were constructed to evaluate the ability of serum PSA to predict threshold prostate sizes in men with BPH. The ROC curve analyses revealed that PSA had good predictive value for assessing prostate volume, with areas under the curve ranging from 0.76 to 0.78 for various prostate volume cutoff points (30, 40, and 50 mL). Conclusions. Prostate volume is strongly related to serum PSA in men with BPH and no evidence of prostate cancer, and the relationship depends on age. Since treatment outcome or risk of long-term complications depend on baseline prostate volume, serum PSA can estimate the degree of prostate enlargement sufficiently accurately to be useful for therapeutic decision making. To achieve a specificity of 70% while maintaining a sensitivity between 65% and 70%, approximate age-specific criteria for detecting men with prostate glands exceeding 40 mL are PSA > 1.6 ng/mL, >2.0 ng/mL, and >2.3 ng/mL for men with BPH in their 50s, 60s, and 70s, respectively.

Can the intraprostatic concentration of epidermal growth factor influence the variance of serum prostate specific antigen levels in patients with benign prostatic hyperplasia?

PURPOSE

Except for prostate volume, little is known about the factors influencing serum prostate specific antigen (PSA) levels. Considering that dihydrotestosterone and epidermal growth factor are regulators of the proliferation and differentiation in the epithelial component of human prostate tissue and that PSA is produced only by the epithelial cells of the gland, studies were performed on patients with a histological diagnosis of benign prostatic hyperplasia (BPH) to establish whether a significant association exists between the intraprostatic concentration of dihydrotestosterone or epidermal growth factor and serum PSA levels.

MATERIALS AND METHODS

A total of 20 patients with BPH who had not been previously treated were part of a larger study on the correlation among PSA, prostate volume and age, and were evaluated according to the algorithm in the guidelines of the international consultation on BPH. All men underwent open suprapubic prostatectomy to enucleate the entire adenoma and in each case sections were made in the periurethral, subcapsular and intermediate zones of the BPH tissue. Dihydrotestosterone and epidermal growth factor concentrations were evaluated by radioimmunoassay in the periurethral zone and in total BPH tissue.

RESULTS

In these 20 patients with BPH serum PSA levels were significantly associated with epidermal growth factor but not with dihydrotestosterone concentrations in total BPH tissue (r = 0.7762, p = 0.00002836 and r = 0.3923, p = 0.0956307, respectively). A stronger association was found between PSA levels and the periurethral concentration of epidermal growth factor and dihydrotestosterone (r = 0.8117, p = 0.000005 and r = 0.5656, p = 0.0098326, respectively). On the contrary, epidermal growth factor and dihydrotestosterone were not significantly associated with prostate volume (p = 0.957415 and p = 0.531439, respectively).

CONCLUSIONS

To our knowledge this study is the first report in the literature to demonstrate an association between serum PSA, and dihydrotestosterone and epidermal growth factor levels, particularly in the periurethral zone of human BPH tissue. These data suggest the importance of epidermal growth factor and dihydrotestosterone in influencing serum PSA levels.