Longitudinal PSA changes in men with and without prostate cancer: assessment of prostate cancer risk

Predicting the Diagnosis of Prostate Cancer with a Novel Blood-Based Biomarker: Comparison of Its Performance with Prostate-Specific Antigen

The purpose of this study was to assess the efficacy, specificity, and predictive value of a newly discovered biomarker, Zinc finger-like1 protein (referred to as neuroendocrine marker, NEM) for the detection of prostate cancer (PCa). We retrospectively analyzed banked plasma samples from 508 men, with a median age of 67 years (range 48-97), to compare the performance of NEM and PSA in predicting subsequent histologic PCa. The cohort consisted of four groups of patients visiting a urology clinic: (1) patients not diagnosed with either benign prostatic disease or prostate cancer (PCa) were defined as normal; (2) patients diagnosed with benign hyperplasia (BPH) but not PCa; (3) patients with confirmed PCa; and (4) patients with cancer other than PCa. The normal men displayed a mean NEM plasma level of 0.948 ± 0.051 ng/mL, which increased to 1.813 ± 0.315 ng/mL in men with BPH, 86.49 ± 15.51 ng/mL in men with PCa, and 10.47 ± 1.029 ng/mL in men with other Ca. The corresponding concentrations of prostate-specific antigen (PSA) in these subjects were 1.787 ± 0.135, 5.405 ± 0.699, 35.77 ± 11.48 ng/mL, and 8.036 ± 0.518, respectively. Receiver operating characteristic (ROC) curve analysis was performed to compare NEM and PSA performance, and the Jouden Index for each biomarker was calculated to determine cut-off points for each biomarker. The area under the ROC curve to predict PCa was 0.99 for NEM and 0.81 for PSA (p < 0.0001). The cut-off for NEM was at 1.9 ng/mL, with sensitivity of 98% and specificity of 97%. The corresponding PSA values were 4.4 ng/mL, with sensitivity of 76% and specificity of 95%. The predictive value of each biomarker in a patient was matched with his pathologic data to determine the accuracy of each biomarker. NEM was more accurate than PSA in differentiating cancer from benign conditions, such as BPH or prostatitis. In conclusion, NEM was a better predictor of PCa than PSA in patients visiting urology clinics. NEM tests, either alone or in conjunction with other biomarkers, provide a reliable, non-invasive, and inexpensive test to remarkably reduce false positives and thereby reduce the number of diagnostic biopsies and associated painful procedures and the loss of quality of life.

Risk-stratified multi-round PSA screening for prostate cancer integrating the screening reference level and subgroup-specific progression indicators

BACKGROUND

Although prostate-specific antigen (PSA) is widely used in prostate cancer (PCa) screening, nearly half of PCa cases are missed and less than one-third of cases are non-lethal. Adopting diagnostic criteria in population-based screening and ignoring PSA progression are presumed leading causes.

METHODS

A total of 31,942 participants with multi-round PSA tests from the PLCO trial were included. Time-dependent receiver-operating-characteristic curves and area under curves (tdAUCs) were performed to determine the screening reference level and the optimal subgroup-specific progression indicator. Effects of risk-stratified multi-round PSA screening were evaluated with multivariable Cox regression and measured with hazard ratio [HR (95%CIs)].

RESULTS

After a median follow-up of 11.6 years, a total of 3484 PCa cases and 216 PCa deaths were documented. The tdAUC of 10-year incidence PCa with PSA was 0.816, and the cut-off value was 1.61 ng/ml. Compared to subgroup with stable negative PSA in both first-round (FR) and last-round (LR) tests [FR(-)/LR(-)], HRs (95%CI) of PCa incidence were 1.66 (1.20-2.29), 8.29 (7.25-9.48), and 14.52 (12.95-16.28) for subgroups with loss of positive PSA[FR(+)/LR(-)], gain of positive PSA[FR(-)/LR(+)], and stable positive PSA[FR(+)/LR(+)]; while HRs(95%CI) of PCa mortality were 1.47 (0.52-4.15), 5.71 (3.68-8.86), and 5.01 (3.41-7.37). After excluding regressive PSA [(namely FR(+)/LR(-)], absolute velocity was the shared optimal progression indicator for subgroups with FR(-)/LR(-), FR(-)/LR(+), and FR(+)/LR(+), with tdAUCs of 0.665, 0.681 and 0.741, and cut-off values of 0.07, 0.21, and 0.33 ng/ml/year. After reclassifying participants into groups with positive and negative progression based on subgroup-specific progression indicators, incidence HR (95%CI) were 2.41 (1.87-3.10), 2.91 (2.43-3.48), and 3.16 (2.88-3.46) for positive progression compared to negative progression within subgroups of FR(-)/LR(-), FR(-)/LR(+), and FR(+)/LR(+), while mortality HR (95%CI) were 2.22 (0.91-5.38), 2.37 (1.28-4.38), and 2.98 (1.94-4.59). To improve screening performances by excluding regressive PSA and low-risk positive progression in FR(-)/LR(-), optimized screening strategy not only significantly reduce 32.4% of missed PCa (54.0% [1881/3484] vs. 21.6% [754/3484], P < 0.001), but also detected additional 8.0% of high-grade PCa (Gleason score 7-10: 36.0% [665/1849] vs. 28.0% [206/736], P < 0.001) than traditional screening strategy.

CONCLUSIONS

Risk-stratified multi-round PSA screening strategy integrating the screening reference level and the optimal subgroup-specific progression indicator of PSA could be recommended as a fundamental strategy to reduce missed diagnosis and improve the detection of high-grade PCa cases.

Prostate-specific antigen velocity in diagnosis and prognosis of prostate cancer - a systematic review

Prostate-specific antigen velocity (PSAV) is widely used to detect PC and predict its progression. In this study, we qualitatively synthesized the currently available evidence from published studies regarding the PSAV role in PC. Electronic databases were searched to find relevant articles published until January 2019. Inclusion and exclusion criteria were applied to identify related papers. Eventually, data extraction followed by evidence synthesis was conducted. Full-text screening resulted in 42 included studies. Multiple definitions and intervals were used for PSAV calculation across studies. Results from the included studies were conflicting regarding the role of PSAV in detecting PC and predicting progression in active surveillance cases. However, there is evidence that PSAV may have a predictive role in post-treated men. There is no clear-cut evidence from the published literature to support the use of PSAV in clinical practice.

Targeting citrate as a novel therapeutic strategy in cancer treatment

An important feature shared by many cancer cells is drastically altered metabolism that is critical for rapid growth and proliferation. The distinctly reprogrammed metabolism in cancer cells makes it possible to manipulate the levels of metabolites for cancer treatment. Citrate is a key metabolite that bridges many important metabolic pathways. Recent studies indicate that manipulating the level of citrate can impact the behaviors of both cancer and immune cells, resulting in induction of cancer cell apoptosis, boosting immune responses, and enhanced cancer immunotherapy. In this review, we discuss the recent developments in this emerging area of targeting citrate in cancer treatment. Specifically, we summarize the molecular basis of altered citrate metabolism in both tumors and immune cells, explore the seemingly conflicted growth promoting and growth inhibiting roles of citrate in various tumors, discuss the use of citrate in the clinic as a novel biomarker for cancer progression and outcomes, and highlight the new development of combining citrate with other therapeutic strategies in cancer therapy. An improved understanding of complex roles of citrate in the suppressive tumor microenvironment should open new avenues for cancer therapy.

Potential effect of anti-inflammatory drug use on PSA kinetics and subsequent prostate cancer diagnosis: Risk stratification in black and white men with benign prostate biopsy

BACKGROUND

Rising prostate-specific antigen (PSA) levels are associated with both increased risk of prostate cancer and prostatic inflammation. The confounding effects of inflammation on the utility of PSA kinetics to predict prostate cancer may be partially mitigated by anti-inflammatory drug use. We investigated the influence of anti-inflammatory drug use on the association of PSA kinetics with prostate cancer risk.

METHODS

We studied 488 prostate cancer case-control pairs (290 white, 198 African American (AA)) nested in a retrospective cohort of men with a benign prostate biopsy. A series of multivariable models estimated prostate cancer risk associated with PSA velocity (PSAV) at different levels of anti-inflammatory drug use while adjusting for the presence of both clinical and histologic prostatitis.

RESULTS

In men with one, two, or three or more courses of anti-inflammatory drug use, for each ng/mL/year increase in PSAV, prostate cancer risk increased 1.21-fold, 1.83-fold, and 1.97-fold, respectively ( P < 0.0001). In controls with histologic prostatitis, anti-inflammatory drug use was associated with a significantly lower PSAV ( P < 0.0001). This association was not observed in men with histologic prostatitis who were subsequently diagnosed with prostate cancer. A positive interaction between anti-inflammatory drug use and PSAV-associated prostate cancer risk was only observed in AA men, as well as a strong positive association between any anti-inflammatory drug use and clinical prostatitis ( P = 0.004).

CONCLUSIONS

In men with benign prostate biopsy, accounting for the presence of histologic prostatitis and anti-inflammatory drug use, particularly in AA men, may help distinguish between men with rising PSA because of prostatitis vs undiagnosed cancer.

Prostate-specific antigen velocity in a prospective prostate cancer screening study of men with genetic predisposition

BACKGROUND

Prostate-specific antigen (PSA) and PSA-velocity (PSAV) have been used to identify men at risk of prostate cancer (PrCa). The IMPACT study is evaluating PSA screening in men with a known genetic predisposition to PrCa due to BRCA1/2 mutations. This analysis evaluates the utility of PSA and PSAV for identifying PrCa and high-grade disease in this cohort.

METHODS

PSAV was calculated using logistic regression to determine if PSA or PSAV predicted the result of prostate biopsy (PB) in men with elevated PSA values. Cox regression was used to determine whether PSA or PSAV predicted PSA elevation in men with low PSAs. Interaction terms were included in the models to determine whether BRCA status influenced the predictiveness of PSA or PSAV.

RESULTS

1634 participants had ⩾3 PSA readings of whom 174 underwent PB and 45 PrCas diagnosed. In men with PSA >3.0 ng ml-l, PSAV was not significantly associated with presence of cancer or high-grade disease. PSAV did not add to PSA for predicting time to an elevated PSA. When comparing BRCA1/2 carriers to non-carriers, we found a significant interaction between BRCA status and last PSA before biopsy (P=0.031) and BRCA2 status and PSAV (P=0.024). However, PSAV was not predictive of biopsy outcome in BRCA2 carriers.

CONCLUSIONS

PSA is more strongly predictive of PrCa in BRCA carriers than non-carriers. We did not find evidence that PSAV aids decision-making for BRCA carriers over absolute PSA value alone.

Racial differences in longitudinal changes in serum prostate-specific antigen levels: the Olmsted County Study and the Flint Men's Health Study

OBJECTIVE

To determine the distribution of, and racial differences in, changes in prostate-specific antigen (PSA) from a population-based sample of men.

MATERIALS AND METHODS

Data from 2 prospective cohort studies of a random sample of white men, aged 40-79 years in 1990, followed biennially through 2007, and African American men, aged 40-79 years in 1996, followed through 2000, were examined to assess the longitudinal changes in PSA concentrations. Serum PSA levels were determined at each examination for both cohorts and observations after a diagnosis of prostate cancer or treatment of benign prostatic hyperplasia were censored. The observed and estimated annual percentage of change in the serum PSA levels were examined by race.

RESULTS

At baseline, the median PSA level in the white men did not differ from the median level observed in the African American men (white men 0.9 ng/mL; African American men 0.9 ng/mL; P = .48). However, African American men had a much more rapid increase in the PSA level over time compared with the white men (median annual percent change in PSA for white men 3.6%/y, African American men 7.9%/y; P <.001).

CONCLUSION

These data suggest that African American men have more rapid rates of change in the PSA levels over time. If the difference in the rate of changes between African American and white men is an early indicator of future prostate cancer diagnosis, earlier detection in African American men could help to alleviate the racial disparities in prostate cancer diagnosis and mortality.

A longitudinal study of PSA and its influential factors in a cohort of Chinese men with initial PSA levels less than 4 ng ml(-1)

To evaluate the longitudinal change in prostate-specific antigen (PSA) and the influence of initial PSA on the PSA change. We retrospectively analysed health examination data collected at Beijing Hospital from March 2007 to November 2011. Men with an initial PSA levels less than 4 ng ml(-1) and an annual PSA test for 5 years were enrolled into the study. The men were separated into four groups by the initial PSA level (0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng ml(-1)), and the difference in PSA change among the four groups was analysed. A total of 1330 men were enrolled into the study. The mean age, initial PSA and PSA velocity (PSAV) were 58.17 ± 14.63 (range 24-91) years, 1.18 ± 0.79 (range 0-4) ng ml(-1) and 0.04 ± 0.25 (range -1.34-2.02) ng ml(-1) year(-1). Pearson's correlation analysis showed no correlation between initial PSA and PSAV (r=-0.036, P=0.189). The PSAV of the 0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng ml(-1) initial PSA groups was 0.03 ± 0.11, 0.07 ± 0.32, 0.03 ± 0.34 and -0.01 ± 0.43 ng ml(-1) year(-1), respectively (P=0.06). As the initial PSA increased, the percentage of having a PSAV over 0.75 ng ml(-1) year(-1) and a negative PSAV both significantly increased. Males with a baseline PSA of 0-0.99, 1-1.99, 2-2.99 and 3-3.99 ng ml(-1) had a 1.88%, 6.16%, 16.30% and 57.81% chance, respectively, that their PSA would increase above 4.0 ng ml(-1) over the following 4 years (P<0.0001). The PSAV has no correlation with the initial PSA level. However, as the initial PSA increases, the chance that males will have an abnormal PSA or PSAV in the future increases.

When does combining markers improve classification performance and what are implications for practice?

When an existing standard marker does not have sufficient classification accuracy on its own, new markers are sought with the goal of yielding a combination with better performance. The primary criterion for selecting new markers is that they have good performance on their own and preferably be uncorrelated with the standard. Most often linear combinations are considered. In this paper, we investigate the increment in performance that is possible by combining a novel continuous marker with a moderately performing standard continuous marker under a variety of biologically motivated models for their joint distribution. We find that an uncorrelated continuous marker with moderate performance on its own usually yields only minimally improved performance. We identify other settings that lead to large improvements, including a novel marker that has very poor performance on its own but is highly correlated with the standard and a novel marker with poor to moderate performance that is highly correlated with the standard but only in one class category. These results suggest changing current strategies for identifying markers to be included in panels for possible combination. Using simulated and real datasets, we examine the merits of a broadened strategy that selects panels of markers as candidates on the basis of their joint performance with existing markers, compared with the standard strategy that selects markers on the basis of their marginal performance. We find that a broadened strategy can be fruitful but necessitates using studies with large numbers of subjects.

Prostate-specific antigen velocity versus prostate-specific antigen doubling time for prediction of 11C choline PET/CT in prostate cancer patients with biochemical failure after radical prostatectomy

PURPOSE

We previously showed that prostate-specific antigen (PSA) doubling time (PSADT) is a significant predictor of 11C choline positron emission tomography/computed tomography (PET/CT) findings in prostate cancer (PCa) patients. This study compared PSA velocity (PSAV) and PSADT to predict 11C choline PET/CT findings.

MATERIALS AND METHODS

PSAV and PSADT were retrospectively calculated in 170 PCa patients with biochemical failure after radical prostatectomy, who underwent 11C choline PET/CT for restaging of disease.

RESULTS

Median PSA was 1.25 ng/mL (range: 0.23-48.6 ng/mL), and median PSAV was 0.99 ng/mL/y (range: 0.11-98.9 ng/mL/y). Patients with positive 11C choline PET/CT (n = 75) had significantly (P < 0.05) higher PSAV than patients with negative 11C choline PET/CT (n = 95) (6.93 ± 13.08 vs. 1.23 ± 2.03 ng/mL/y). The percent of patients with positive 11C choline PET/CT was 21% for PSAV <1 ng/mL/y, 56% for PSAV between 1 and 2 ng/mL/y, and 76% for PSAV >2 ng/mL/y. The quality of fitting (r2) of PSA values according to the exponential function (PSADT) was significantly (P < 0.05) better than the quality of fitting according to the linear function (PSAV) in the entire sample and in all anatomic regions. At multivariate analysis, trigger PSA, PSADT but not PSAV obtained the statistical significance (P < 0.05).

CONCLUSIONS

PSAV can be used to stratify the risk of positive 11C choline PET/CT in PCa patients with biochemical failure. Patients with PSAV >1 ng/mL/y should be selected to increase the positive detection rate of 11C choline PET/CT. The greater statistical power of PSADT compared with PSAV could be related to the better capability of fitting time-dependent changes in PSA values, thereby better reflecting the natural growth of recurrent PCa.

Assessing prostate cancer growth with citrate measured by intact tissue proton magnetic resonance spectroscopy

BACKGROUND

Annual PSA tests have led to a significant increase in the number of prostate cancer (PCa) cases diagnosed. This increased incidence has led to overtreatment of many patients, as current pathology often cannot distinguish latent from aggressive PCa. Studies have shown that the depletion of zinc in prostate cells correlated with cell-line growth rates, and may therefore relate to the progression of PCa. Furthermore, as zinc is normally an inhibitor of citrate oxidation, the reduction of zinc in PCa may cause a decrease in citrate secretion levels in the glandular epithelia of PCa patients.

METHODS

Using high-resolution magic angle spinning proton magnetic resonance spectroscopy followed by quantitative histopathology, we investigate unit histo-benign prostate epithelial citrate concentrations in intact tissue samples obtained from 18 patients with pre-surgical PSA values less than 20 ng/ml. Using these data, we evaluate correlations between citrate concentrations and PSA velocities, densities and blood percent-free PSA.

RESULTS

We observe different linear patterns between citrate concentrations and histo-benign glandular epithelia from patients of different PSA velocities. More importantly, we obtain a significant correlation between PSA velocity, density and percent-free PSA, and citrate concentrations in unit volume of histo-benign epithelial glands of the peripheral zone.

CONCLUSIONS

Low levels of citrate in unit volume represent rapidly increasing PSA values, and, therefore, may be used as an indicator of fast-growing PCa. Thus, tissue samples obtained at the time of biopsy may be evaluated for their citrate concentrations for the prediction of PCa growth rates, allowing for the implementation of alternative treatment options and reducing overtreatment.

Sauver JL, Klee GG, Girman CJ, Lieber MM. Sixteen-year longitudinal changes in serum prostate-specific antigen levels: the olmsted county study

OBJECTIVE

To determine the distribution of longitudinal changes in serum prostate-specific antigen (PSA) levels from a population-based sample of men.

PATIENTS AND METHODS

In this prospective cohort study, a random sample of Olmsted County, Minnesota, men aged 40 to 79 years in 1990 were followed up biennially from January 1, 1990, through August 29, 2007. Serum PSA levels were determined at each examination, and men were censored for follow-up with a diagnosis of prostate cancer or treatment for benign prostatic hyperplasia. The empirical distributions of annual percent change and annual absolute change in serum PSA level were calculated and tabulated, including the median and 75th and 95th percentiles.

RESULTS

For men with PSA measurements 2 years apart, the median annual percent change in serum PSA level was 4.83% and the 95th percentile was about 49.76%. The variability in estimated annual change decreased with increasing time between assessments, with a 95th percentile of 21.82% after 8 or more years between assessments. Although the median absolute change per year increased with increasing age, the median percent change per year was fairly consistent across age groups.

CONCLUSION

These data demonstrate that, with shorter intervals between assessments, greater variability should be expected. These distributions should prove helpful to patients and clinicians in interpreting changes in serum PSA levels observed in typical clinical practices.

[Diagnostics and therapy of localized prostate cancer: a problem-oriented account]

The diagnostics and treatment of prostate cancer (PCa) are currently encumbered with several problems: Only a small proportion of men attend medical check-ups. The PSA count, although invaluable in the early detection of PCa, is not being paid for by health insurance schemes, because its indiscriminate use would result in overdiagnosis of PCa which, in turn would burden patients with avoidable morbidity and the mutually supportive community with unnecessary costs. Accordingly, some clinically insignificant tumors are being detected and treated although treatment appears unnecessary. However, more importantly too many significant tumors which need early detection to be cured are being discovered too late due to diagnostic possibilities being neglected. At least one third of all tumors discovered are still found at a locally advanced stage. Following diagnosis by biopsy the therapeutic recommendations are guided by the clinical stage. In spite of recent advances in MR-based imaging the exact local extent of tumors remains uncertain. Prognostic and predictive biomarkers for aid in therapeutic decisions are also lacking. The more defensive therapeutic strategies, such as active surveillance should be recommended with special precautions in patients younger than 65 years, in the light of new Scandinavian data. Among the curative treatments radical prostatectomy claims the primary position. Minimally-invasive surgery for PCa has not come up to expectations regarding superior local tumor control, less perioperative complication, or better functional results, at the expense of appreciably higher costs.

Prostate-specific antigen (PSA) isoform p2PSA in combination with total PSA and free PSA improves diagnostic accuracy in prostate cancer detection

BACKGROUND

Novel markers for prostate cancer (PCa) detection are needed. Total prostate-specific antigen (tPSA) and percent free prostate-specific antigen (%fPSA=tPSA/fPSA) lack diagnostic specificity.

OBJECTIVE

To evaluate the use of prostate-specific antigen (PSA) isoforms p2PSA and benign prostatic hyperplasia-associated PSA (BPHA).

DESIGN, SETTING, AND PARTICIPANTS

Our study included 405 serum samples from the Rotterdam arm of the European Randomised Study of Screening for Prostate Cancer and 351 samples from the Urology Department of Innsbruck Medical University.

MEASUREMENTS

BPHA, tPSA, fPSA, and p2PSA levels were measured by Beckman-Coulter Access Immunoassay. In addition, the Beckman Coulter Prostate Health Index was calculated: phi=(p2PSA/fPSA)×√(tPSA).

RESULTS AND LIMITATIONS

The p2PSA and phi levels differed significantly between men with and without PCa. No difference in BPHA levels was observed. The highest PCa predictive value in both cohorts was achieved by phi with areas under the curve (AUCs) of 0.750 and 0.709, a significant increase compared to tPSA (AUC: 0.585 and 0.534) and %fPSA (AUC: 0.675 and 0.576). Also, %p2PSA (p2PSA/fPSA) showed significantly higher AUCs compared to tPSA and %fPSA (AUC: 0.716 and 0.695, respectively). At 95% and 90% sensitivity, the specificities of phi were 23% and 31% compared to 10% and 8% for tPSA, respectively. In both cohorts, multivariate analysis showed a significant increase in PCa predictive value after addition of p2PSA to a model consisting of tPSA and fPSA (increase in AUC from 0.675 to 0.755 and from 0.581 to 0.697, respectively). Additionally, the specificity at 95% sensitivity increased from 8% to 24% and 7% to 23%, respectively. Furthermore, %p2PSA, phi, and the model consisting of tPSA and fPSA with or without the addition of p2PSA missed the least of the tumours with a biopsy or pathologic Gleason score ≥7 at 95% and 90% sensitivity.

CONCLUSIONS

This study shows significant increases in PCa predictive value and specificity of phi and %p2PSA compared to tPSA and %fPSA. p2PSA has limited additional value in identifying aggressive PCa (Gleason score ≥7).

Tyrol Prostate Cancer Demonstration Project: early detection, treatment, outcome, incidence and mortality

OBJECTIVE

To evaluate the effectiveness of a well-controlled programme of early detection and treatment of prostate cancer in the population of Tyrol, Austria, where such a programme of early detection and treatment was initiated in 1988 and where prostate-specific antigen (PSA) testing was offered for free to all men aged 45-75 years from 1993.

SUBJECTS AND METHODS

Comparison of prostate cancer mortality rates in Tyrol and the rest of Austria was accomplished through a generalized additive model. A piecewise linear change-point Poisson regression model was used to compare mortality rates in Tyrol and the rest of Austria. Standardized mortality ratios were calculated with reference to the mortality rates in 1986-1990.

RESULTS

In all, 86.6% of eligible men have been tested at least once since 1993. Cancer deaths in Tyrol in 2005 were 54% (95% confidence interval [CI] 34-69%) lower than expected compared with 29% (95% CI 22-35%) in the rest of Austria. The decreasing trend in prostate cancer mortality was significantly greater in Tyrol compared with the rest of Austria (P = 0.001). A significant migration to lower stage disease occurred and radical prostatectomy was associated with low morbidity.

CONCLUSIONS

In the Tyrol region where treatment is freely available to all patients, where widespread PSA testing and treatment with curative intent occurs, there was a reduction in prostate cancer mortality rates which was significantly greater than the reduction in the rest of Austria. This reduction in prostate cancer mortality is most probably due to early detection, consequent down-staging and effective treatment of prostate cancer.

[Therapy of male hypogonadism]

One of the most frequent, but also most undiagnosed, endocrinopathies is male hypogonadism (testosterone deficiency). Understanding the variety of clinical pictures male hypogonadism exhibits is pivotal for diagnosis and putative treatment. There can be disturbances of mood and cognitive abilities as well as sexual functions. Further on, a decrease in muscle mass and strength, an accumulation of body fat and osteopenia/osteoporosis as well as anemia might be observed. There are indications that insulin sensitivity is mitigated in a state of androgen depletion, especially due to an inverse association of testosterone to the metabolic syndrome. In older men, symptoms of androgen deficiency may feature a differential profile due to accompanying co-morbidities. Restoring serum testosterone levels by substitution therapy can markedly attenuate, if not relieve, the clinical picture of hypogonadism. New treatment modalities have been introduced, including short-acting transdermal as well as long-acting depot preparations. Herewith, the diagnostic pathways to describe or exclude male hypogonadism and as well as various options of initiation and surveillance of testosterone substitution therapy are elucidated. Future perspectives of andrology regarding metabolic and pharmacogenetic aspects are discussed.

Relationship of prostate-specific antigen velocity to histologic findings in a prostate cancer screening program

OBJECTIVES

For prostate cancer screening, the role of prostate-specific antigen (PSA) velocity (PSAV) in conjunction with total PSA is controversial. We evaluated the relationship of PSAV to histologic findings on biopsy and assessed whether PSAV provides independent predictive information.

METHODS

From a community-based cohort of 25,276 men screened from 1991 to 2001, 1851 underwent a first biopsy for an elevated PSA and nonsuspicious digital rectal examination with a PSAV available from the year before biopsy. We analyzed the association between PSAV and biopsy histology.

RESULTS

The histologic findings on biopsy were cancer in 468 (25%), prostatic inflammation in 135 (7%), and benign prostate tissue in 1248 (68%). The cancer detection rate was associated with PSAV and, depending on PSAV, ranged from 13% to 36% (P <0.001). Among men with a PSAV less than 0.5 ng/mL per year, the cancer rate ranged from 27% to 36%, at a PSAV of 0.5 to 3.0 ng/mL per year was 24% to 28%, and at a PSAV greater than 3.0 ng/mL per year was 13% to 18%. On multivariable analysis adjusting for age and PSA, PSAV was independently associated with risk of cancer on biopsy (P <0.0005). The rate of prostatic inflammation was directly associated with PSAV (PSAV of 3.0 ng/mL per year or less: 5% to 9%; PSAV greater than 3.0 ng/mL per year: 11% to 13%, P = 0.01).

CONCLUSIONS

In screened men with an elevated PSA undergoing biopsy, PSAV provides independent predictive information for estimating prostate cancer risk. Modest increases in PSA are associated with an increased risk of cancer, whereas more dramatic PSA rises are associated with a diminishing risk of cancer and higher rate of inflammation.

Screening for prostate cancer in U.S. men ACPM position statement on preventive practice

INTRODUCTION

Prostate cancer is the leading cancer in U.S. men, and the third leading cause of cancer deaths. Principal screening tests for detection of asymptomatic prostate cancer include digital rectal examination (DRE) and measurement of the serum tumor marker, prostate-specific antigen (PSA). There are risks and benefits associated with prostate cancer screening. Randomized controlled trials of screening by DRE and PSA are limited to two previously published studies. Two other large-scale randomized controlled trials are currently in progress.

METHODS

This study reviewed the efficacy of DRE and PSA for prostate cancer screening found in the medical literature prior to July 2007.

RESULTS

Applications of PSA screening tests used in clinical practice include (1) a PSA cutoff of 4 ng/ml, (2) age-specific PSA, (3) PSA velocity, (4) PSA density, and (5) percent free PSA. Prostate cancer screening can detect early disease and offers the potential to decrease morbidity and mortality. Prostate cancer screening benefits, however, remain unproven, pending results of ongoing trials. There is currently no convincing evidence that early screening, detection, and treatment improves mortality. Limitations of prostate cancer screening include potential adverse health effects associated with false-positive and negative results, and treatment side effects.

CONCLUSIONS

The American College of Preventive Medicine concludes that there is insufficient evidence to recommend routine population screening with DRE or PSA. Clinicians caring for men, especially African-American men and those with positive family histories, should provide information about potential benefits and risks of prostate cancer screening, and the limitations of current evidence for screening, in order to maximize informed decision making.

[Differential therapy of prostate cancer]

Prostate cancer has become the most common malignancy in males worldwide. Standard therapy in local confined prostate cancer with curative intent is a radical ablation of the gland. Brachytherapy seems to be an alternative treatment but long-term results are not yet available. In cases of advanced disease androgen deprivation is applied to eliminate testosterone which is the natural stimulator of tumor growth. The application of chemotherapy is limited to androgen-independent disease without curative intention. Standard chemotherapy is Docetaxel. Both early detection and aftercare are based on measurement of prostate-specific antigen.

Methods of Calculating Prostate-Specific Antigen Velocity

OBJECTIVES

Numerous methods of calculating PSA velocity (PSAV) are used and have the potential to produce differing PSAV results from the same PSA data. We calculated PSAV using three common methods and compared differences between the methods and their predictive value for prostate cancer diagnosis.

METHODS

From a population-based database of PSA results, men with initial PSA<10.0 ng/ml and a subsequent diagnosis of prostate cancer or benign histology were identified. Those with > or =3 PSA tests before diagnosis carried out over a minimum of 18 mo were included. PSAV was calculated by using three methods: The differences between the methods and test characteristics of each method were compared.

RESULTS

Of the 2204 men included, 716 (32.5%) were diagnosed with prostate cancer and 1488 (67.5%) benign histology. PSAV differed markedly in each method of calculation. The LR and FL methods had similar predictive values, which were higher than the AE method. There was strong agreement for cancer diagnosis between LR and FL (kappa=0.85), with weaker agreement between LR/AE and FL/AE (kappa=0.69 and 0.66, respectively).

CONCLUSIONS

Methods used to calculate PSAV using the same PSA data can produce markedly different results. Linear regression should be the method of choice for calculating PSAV. Using first and last PSA values only may be adequate for everyday clinical use, as long as measurements are separated by a sufficiently long time period.

Prostate-specific antigen velocity and prostate cancer gleason grade and stage

BACKGROUND

Increased preoperative prostate-specific antigen (PSA) velocity (PSAV) has been associated with increased prostate cancer mortality and higher Gleason scores. The authors evaluated the relation between PSAV, biopsy Gleason score, and pathologic stage in men who were enrolled in a prostate cancer screening trial.

METHODS

Data were analyzed from 1441 men who were enrolled in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial who received > or =2 PSA screens and were diagnosed with prostate cancer within 1 year of the last screen. PSAV was estimated by using all screening PSA values within 6 years prediagnosis.

RESULTS

Both PSA and PSAV were related to biopsy Gleason score. The multivariable odds ratios (OR), controlling for PSA and demographics, for having a Gleason score of 7 to 10 were 1.3 (95% confidence interval [95% CI], 0.9-1.9), 2.2 (95% CI, 1.5-3.3), and 2.3 (95% CI, 1.4-3.9) for men with PSAV values from 0.5 to 1 ng/mL per year, from 1 to 2 ng/mL per year, and >2 ng/mL per year, respectively, compared with men who had PSAV values <0.5 ng/mL per year. The median PSAV was 0.60 ng/mL per year for men with Gleason scores from 2 to 6 versus 0.84 ng/mL per year for men with Gleason scores from 7 to 10 (P < .0001). Among 658 men who underwent prostatectomy, both PSA and PSAV were associated with advanced pathologic stage in univariate analyses; however, when the analysis controlled for clinical stage and biopsy Gleason score, the associations of PSA and PSAV were no longer statistically significant.

CONCLUSIONS

PSAV and PSA levels were associated independently with biopsy Gleason score. Among men who underwent prostatectomy, PSAV and PSA were not predictive of advanced pathologic stage when the analysis was controlled for biopsy Gleason score and clinical stage. It cannot be determined yet whether PSAV is predictive of long-term prostate cancer outcome in this cohort.

Implications of Prostate-Specific Antigen Doubling Time as Indicator of Failure after Surgery or Radiation Therapy for Prostate Cancer

OBJECTIVES

To review the methodology of PSA doubling time (PSA DT) calculations and the implications of PSA DT for the follow-up of prostate cancer patients curatively treated with surgery or radiation therapy.

METHODS

A literature search of the most recent articles on PSA DT (those published after 2000) led to the selection of six studies with the largest and best-documented cohorts of patients treated with surgery or irradiation with curative intent.

RESULTS

PSA kinetics, in the form of PSA DT, is the most effective parameter for identifying patients at significant risk for mortality specific to prostate cancer. Thresholds of 3, 6, and 12 mo have shown prognostic significance both in surgical and radiation series, notwithstanding differences in treatment selection, definition of biochemical recurrence, and methods of DT calculation.

CONCLUSIONS

In retrospective studies, PSA DT is a reliable predictor of prognosis; however, prospective validation studies are needed to determine the cut points of PSA DT. Optimal time intervals for calculation and optimal thresholds are still to be determined.

Large-scale study of clinical impact of PSA velocity: long-term PSA kinetics as method of differentiating men with from those without prostate cancer

OBJECTIVES

To assess the longitudinal prostate-specific antigen (PSA) changes in a screening population with or without prostate cancer during a 10-year period.

METHODS

Serial PSA measurements performed during a 10-year period were evaluated in 4272 participants of a screening program who had no evidence of prostate malignancy and 528 men who eventually developed prostate cancer.

RESULTS

Of the 4272 men with no evidence of prostate cancer, the mean total PSA level increased from 1.16 to 1.49 ng/mL during the 10 years, corresponding to a PSA velocity (PSAV) of 0.03 ng/mL/yr. Younger men had lower total PSA values throughout the 10-year period. Of the 528 patients with prostate cancer, the total PSA level increased from 2.19 at 10 years before diagnosis to 6.09 ng/mL at the time of positive biopsy findings, corresponding to a PSAV of 0.39 ng/mL/yr. The PSAV increased in the years before diagnosis (0.225 ng/mL/yr in the 8 to 10 years before diagnosis compared with 0.98 ng/mL/yr in the 2 years before diagnosis). The PSAV was greater in patients with Stage pT3-T4 cancer than in men with organ-confined tumors (median 0.53 versus 0.32 ng/mL/yr; P <0.001).

CONCLUSIONS

In men with prostate cancer, the PSAV was significantly greater than in those without prostate cancer and correlated with pathologic stage and Gleason score but not with prostate volume. In the patients with prostate cancer, the PSAV increased in the years before the diagnosis. In contrast, men without prostate cancer had only slight PSA changes over time. Hence, PSA kinetics may help identify men with potentially curable prostate cancer.

Prostate-specific antigen 'velocity' as a diagnostic test for prostate cancer

BACKGROUND

Prostate-specific antigen "velocity" (slope) is promoted as a diagnostic test for prostate cancer, but its clinical usefulness is uncertain. Accordingly, we evaluated the sensitivity of prostate-specific antigen (PSA) velocity among men who are diagnosed subsequently with prostate cancer.

METHODS

Among 64,545 men receiving primary care at any of nine Veterans Affairs Medical Centers during 1989-1990, 1,313 men at least 50 years old had an incident diagnosis of prostate cancer during 1991-1995. PSA velocity values obtained prior to diagnosis ("test") were compared with results from prostate biopsies ("truth").

RESULTS

Among men (n = 493) with at least two tests before diagnosis, the sensitivity of PSA velocity > or = 0.75 ng/mL/yr was 75.5% (95% confidence interval [CI] 71.7-79.3) overall and 48.1% (95% CI 34.8-61.5) among men with normal values of PSA (< 4.0 ng/mL). Based on published data for specificity and prevalence, the estimated positive predictive value of PSA velocity > or = 0.75 ng/mL/yr is as low as 5%.

CONCLUSION

PSA velocity may have limited usefulness as a diagnostic test for prostate cancer.

Comparison of methods for calculating prostate specific antigen velocity

PURPOSE

Prostate specific antigen velocity is frequently calculated using regression analysis of multiple prostate specific antigen measurements during an interval of 18 to 24 months. It has been reported that the prostate specific antigen velocity in the year before prostate cancer diagnosis is associated with the cancer specific mortality rate following radical prostatectomy and radiation therapy. There are limited data comparing alternate methods of calculating prostate specific antigen velocity. In this study we compared simple arithmetic prostate specific antigen velocity calculations to the more complicated regression analysis using prostate specific antigen measurements from varying intervals to determine whether the methods were interchangeable.

MATERIALS AND METHODS

From 2003 to 2005 a total of 540 men underwent radical retropubic prostatectomy for localized prostate cancer. Preoperative prostate specific antigen velocity was calculated using arithmetic and linear regression methods during 12 and 18-month intervals. The correlation, mean and median prostate specific antigen velocity were compared among methods.

RESULTS

Prostate specific antigen velocity calculations using simple arithmetic and linear regression had a strong correlation when restricted to prostate specific antigen values from 12 months before diagnosis (r = 0.92). When prostate specific antigen measurements beyond 1 year were included in the calculation, prostate specific antigen velocity was significantly lower than in the 12 months before cancer diagnosis.

CONCLUSIONS

Using a simple arithmetic prostate specific antigen velocity calculation yields results comparable to those of the more complicated regression analysis when restricted to prostate specific antigen values from within the year before diagnosis in patients with clinically localized prostate cancer. In this manner arithmetic prostate specific antigen velocity calculations may be used in daily clinical practice to help predict the outcome following definitive therapy. Prostate specific antigen velocity is significantly lower when calculated during a longer interval before prostate cancer diagnosis.

Relapse after radical prostatectomy correlates with preoperative PSA velocity and tumor volume: Results from a screening population

OBJECTIVES

To evaluate, in a screening population, the impact of tumor volume and prostate volume on prostate-specific antigen (PSA) velocity (PSAV) and to find predictors of biochemical failure after radical prostatectomy. Longitudinal PSA changes in men with prostate cancer have been reported to be significantly different from those without prostate cancer.

METHODS

PSAV was assessed in 102 men undergoing radical retropubic prostatectomy. The pathologic findings of specimens obtained at radical retropubic prostatectomy and pelvic lymph node dissection were analyzed separately for all patients.

RESULTS

The median preoperative PSA in the 102 patients was 6.4 ng/mL, the median prostate volume was 32.8 cm3, and the median tumor volume was 1.27 cm3. The PSAV correlated significantly with tumor volume (P <0.05) but not with prostate volume (P = 0.142). The median tumor volume in men with biochemical progression after radical retropubic prostatectomy was 2.55 cm3 versus 0.94 cm3 in men who were free of disease 5 years after surgery. The median PSAV in the year before diagnosis in men with relapse after radical prostatectomy was 1.98 ng/mL/yr versus 1.05 ng/mL/yr in men who had no evidence of disease.

CONCLUSIONS

The results of our study have shown that the main factor contributing to the PSAV in patients with prostate cancer is cancer load and that prostate volume is not significantly associated with the PSAV. Men with a PSAV of more than 2 ng/mL/yr in the year before cancer diagnosis are at a high risk of relapse. The PSAV may be helpful in identifying patients with small tumors and thus increase the detection rate of potentially curable prostate cancers.

Shift of tumor features in patients with clinically localized prostate cancer undergoing radical prostatectomy since the beginning of the PSA era

AIM

To analyze trends of clinical and tumor characteristics over a 12-year period since the beginning of the prostate-specific antigen (PSA) era in a consecutive series of radical prostatectomies.

PATIENTS AND METHODS

Between 1993 and 2004 a consecutive series of 1351 patients underwent radical prostatectomy for clinically localized prostate cancer (PC) in a single institution. Clinical and histopathological information was entered into our computer database and analyzed for changes over time.

RESULTS

The annual frequency of surgical interventions increased from 43 to 160 (272%) during the observation period (r = 0.930; p < 0.01). The detection of PC based solely on pathological PSA levels rose impressively from 7% to 70% (r = 0.986; p < 0.01). The rates of organ-confined disease also increased significantly from 47% to 79% (r = 0.774; p < 0.01). Stage pT3a decreased somewhat from 28% to 18% (r = -0.389; n.s.) whereas pT3b decreased significantly from 26% to 3% (r = -0.729; p < 0.01).

CONCLUSION

During the 12-year period, PC was increasingly detected on the basis of a pathological PSA level only and shifted significantly to more organ-confined stages. With a time delay, these findings are consistent with trends observed in large centers in the USA.

Does PSA Velocity Predict Prostate Cancer in Pre-Screened Populations?

PSA-driven screening has been applied to a large part of the male population in many countries. An elevated PSA in secondary screens may indicate benign enlargement of the prostate rather than prostate cancer. In such cases the yearly rate of increase of PSA (PSA velocity [PSAV]) may improve the test characteristics of PSA.

MATERIALS AND METHODS

Data from the European Randomized Study of Screening for Prostate Cancer Rotterdam are used to study the issue. Relative sensitivity, relative specificity, and positive predictive value (PPV) are calculated. Logistic regression analysis is used to compare odds ratios for positive biopsies. The relationship between PSAV and parameters of tumour aggressiveness is investigated.

RESULTS

Five hundred eighty-eight consecutive participants were identified who presented at their first screening with PSA values <4.0 and who progressed to PSA values >4.0 ng/ml four years later. None were biopsied in round one, all were biopsied in round two. Relative sensitivity and specificity depend strongly on PSAV cut-offs of 0.25-1.0 ng/ml/yr. The use of PSAV cut-offs does not improve the PPV of the PSA cut-off of 4.0 ng/ml, nor do any of the PSAV cut-offs improve the odds ratio for identifying prostate cancer with respect to the cut-off value of 4.0 ng/ml. The rate of aggressive cancers seems to increase with increasing PSAV.

CONCLUSIONS

PSAV does not improve the detection characteristics of a PSA cut-off of 4.0 ng/ml in secondary screening after four years.

Testosterone replacement therapy and the risk of prostate cancer. Is there a link?

Substantial evidence supports the value of testosterone replacement therapy (TRT) in improving quality of life in men with proven aging male syndrome (AMS). Benefits of TRT include improved bone mineral density, reduced fracture risk, increased muscle mass, and improved mood, sense of well being, and libido, among others. There is currently a heated debate about the theoretical association between TRT and the initiation, progression, and aggressiveness of prostate cancer; however, this link has not been uniformly studied, and any results have been contradictory and nonconclusive. Although no clear evidence links TRT to prostate cancer, the possibility of increasing the risk of a clinical manifestation of a latent pre-existing malignancy can influence the decision about TRT use. Current recommendations are to exclude prostate cancer before initiating TRT in men over age 40 and to closely monitor men in the first year of testosterone replacement, followed by observation in subsequent years.