Longitudinal Evaluation of Prostate-Specific Antigen Levels in Men With and Without Prostate Disease

A new promising indicator in prostate cancer screening: Prostate-specific antigen fluctuation rate

OBJECTIVES

To evaluate whether PSA fluctuation can be used to predict the risk of prostate cancer.

MATERIALS AND METHODS

The study included 1244 patients who underwent prostate biopsy at Kartal Dr. Lutfi Kirdar City Hospital between 2013 and 2021 (848 in non-cancer; 396 in cancer). The patient's age, last two PSA values (PSA1 and PSA2) within three months before the biopsy, the duration between two PSAs (days), prostate size (g) and PSA density (PSAD) were all recorded. PSA fluctuation rate (PSAfr) was defined as the change rate between two PSA values.

RESULTS

PSAfr was significantly higher in the non-cancer group than in the prostate cancer group (15.2% (20.5) and 9.6% (14.4), P=.019). A Simple linear regression was used to examine the relationship between PSAfr and other factors such as age, PSA, PSAD, and prostate volume, but it was shown that these had no effect on PSA fluctuations. ROC analysis revealed a relatively low Area Under the Curve (AUC) for PSAfr (AUC, 0.584 (0.515-0.653)). However, the cut-off value of 12.35% was found to be significant, with a sensitivity of 58% and a specificity of 59% (P:.019, 95%CI). The odds ratio, adjusted for age, PSAD, and PSA2, was calculated as 0.545 (0.33-0.89) using logistic regression analysis to show the relationship between prostate cancer and PSAfr. As a result, those with high PSAfr were found to be 1.83 times less likely to be diagnosed with prostate cancer than those with low fluctuations.

CONCLUSION

PSAfr could be used in nomograms to predict prostate cancer risk and reduce the number of unnecessary biopsies.

Opportunistic prostate-specific antigen testing in Norwegian men: a public health challenge

OBJECTIVE

To describe age-specific prostate-specific antigen (PSA) distributions and resulting prostate cancer diagnoses that arise from population-wide opportunistic PSA testing.

PATIENTS AND METHODS

Over 8 million PSA tests were performed on >1.4 million Norwegian men from 2000 to 2020. During this period 43 486 men were diagnosed with localised prostate cancer. Most of the PSA testing reflected opportunistic testing. Age-specific PSA value distributions were constructed for men aged 45-75 years with and without prostate cancer.

RESULTS

The distributions of PSA values in men with and without prostate cancer widened with age and overlapped extensively from 3 to 7 ng/mL. Localised prostate cancer diagnoses increased 10-fold from the age of 45 to 75 years. PSA testing identified intermediate- or high-grade cancers in 21% (95% confidence interval [CI] 19-23%) of men aged 50-54 years and 42% (95% CI 41-43%) of men aged 70-74 years. Grade group (GG)1, GG2, GG3 and ≥GG4 constituted 49%, 31%, 10% and 10% of cancers identified at age 50-54 years and 26%, 26%, 18%, and 30% of cancers identified at age 70-74 years.

CONCLUSION

Opportunistic PSA testing increases with ageing and often generates values that cannot discriminate benign prostate enlargement from prostate cancer. A clinical cascade using additional imaging or serum tests is necessary to avoid negative biopsies and the overdiagnosis of indolent disease. The declining specificity of PSA testing with ageing poses a significant public health challenge especially among older men aged ≥70 years.

A big data-based prediction model for prostate cancer incidence in Japanese men

To define a normal range for PSA values (ng/mL) by age and create a prediction model for prostate cancer incidence. We conducted a retrospective analysis using 263,073 observations of PSA values in Japanese men aged 18-98 years (2007-2017), including healthy men and those diagnosed with prostate cancer. Percentiles for 262,639 PSA observations in healthy men aged 18-70 years were calculated and plotted to elucidate the normal fluctuation range for PSA values by age. Univariable and multivariable logistic regression analyses were performed to develop a predictive model for prostate cancer incidence. PSA levels and PSA velocity increased with age in healthy men. However, there was no difference in PSA velocity with age in men diagnosed with prostate cancer. Logistic regression analysis showed an increased risk of prostate cancer for PSA slopes ranging from 0.5 to 3.5 ng/mL/year. This study provides age-specific normal fluctuation ranges for PSA levels in men aged 18-75 years and presents a novel and personalized prediction model for prostate cancer incidence. We found that PSA slope values of > 3.5 ng/mL/year may indicate a rapid increase in PSA levels caused by pathological condition such as inflammation but are unlikely to indicate cancer risk.

Infectivity-Enhanced, Conditionally Replicative Adenovirus for COX-2-Expressing Castration-Resistant Prostate Cancer

BACKGROUND

The development of conditionally replicative adenoviruses (CRAds) for castration-resistant prostate cancer (CRPC), particularly neuroendocrine prostate cancer (NEPC), has two major obstacles: choice of control element and poor infectivity. We applied fiber-modification-based infectivity enhancement and an androgen-independent promoter (cyclooxynegase-2, COX-2) to overcome these issues.

METHODS

The properties of the COX-2 promoter and the effect of fiber modification were tested in two CRPC cell lines (Du-145 and PC3). Fiber-modified COX-2 CRAds were tested in vitro for cytocidal effect as well as in vivo for antitumor effect with subcutaneous CRPC xenografts.

RESULTS

In both CRPC cell lines, the COX-2 promoter showed high activity, and Ad5/Ad3 fiber modification significantly enhanced adenoviral infectivity. COX-2 CRAds showed a potent cytocidal effect in CRPC cells with remarkable augmentation by fiber modification. In vivo, COX-2 CRAds showed an antitumor effect in Du-145 while only Ad5/Ad3 CRAd showed the strongest antitumor effect in PC3.

CONCLUSION

COX-2 promoter-based, infectivity-enhanced CRAds showed a potent antitumor effect in CRPC/NEPC cells.

Aptamers as Theragnostic Tools in Prostate Cancer

Despite of the capacity that several drugs have for specific inhibition of the androgen receptor (AR), in most cases, PCa progresses to an androgen-independent stage. In this context, the development of new targeted therapies for prostate cancer (PCa) has remained as a challenge. To overcome this issue, new tools, based on nucleic acids technology, have been developed. Aptamers are small oligonucleotides with a three-dimensional structure capable of interacting with practically any desired target, even large targets such as mammalian cells or viruses. Recently, aptamers have been studied for treatment and detection of many diseases including cancer. In PCa, numerous works have reported their use in the development of new approaches in diagnostics and treatment strategies. Aptamers have been joined with drugs or other specific molecules such as silencing RNAs (aptamer–siRNA chimeras) to specifically reduce the expression of oncogenes in PCa cells. Even though these studies have shown good results in the early stages, more research is still needed to demonstrate the clinical value of aptamers in PCa. The aim of this review was to compile the existing scientific literature regarding the use of aptamers in PCa in both diagnosis and treatment studies. Since Prostate-Specific Membrane Antigen (PSMA) aptamers are the most studied type of aptamers in this field, special emphasis was given to these aptamers.

Evaluation of machine learning strategies for imaging confirmed prostate cancer recurrence prediction on electronic health records

BACKGROUND

The main screening parameter to monitor prostate cancer recurrence (PCR) after primary treatment is the serum concentration of prostate-specific antigen (PSA). In recent years, Ga-68-PSMA PET/CT has become an important method for additional diagnostics in patients with biochemical recurrence.

PURPOSE

While Ga-68-PSMA PET/CT performs better, it is an expensive, invasive, and time-consuming examination. Therefore, in this study, we aim to employ modern multivariate Machine Learning (ML) methods on electronic health records (EHR) of prostate cancer patients to improve the prediction of imaging confirmed PCR (IPCR).

METHODS

We retrospectively analyzed the clinical information of 272 patients, who were examined using Ga-68-PSMA PET/CT. The PSA values ranged from 0 ng/mL to 2270.38 ng/mL with a median PSA level at 1.79 ng/mL. We performed a descriptive analysis using Logistic Regression. Additionally, we evaluated the predictive performance of Logistic Regression, Support Vector Machine, Gradient Boosting, and Random Forest. Finally, we assessed the importance of all features using Ensemble Feature Selection (EFS).

RESULTS

The descriptive analysis found significant associations between IPCR and logarithmic PSA values as well as between IPCR and performed hormonal therapy. Our models were able to predict IPCR with an AUC score of 0.78 ± 0.13 (mean ± standard deviation) and a sensitivity of 0.997 ± 0.01. Features such as PSA, PSA doubling time, PSA velocity, hormonal therapy, radiation treatment, and injected activity show high importance for IPCR prediction using EFS.

CONCLUSION

This study demonstrates the potential of employing a multitude of parameters into multivariate ML models to improve identification of non-recurring patients compared to the current focus on the main screening parameter (PSA). We showed that ML models are able to predict IPCR, detectable by Ga-68-PSMA PET/CT, and thereby pave the way for optimized early imaging and treatment.

Contributions of Social Factors to Disparities in Prostate Cancer Risk Profiles among Black Men and Non-Hispanic White Men with Prostate Cancer in California

BACKGROUND

Black men are more likely than Non-Hispanic White (NHW) men to be diagnosed with high-risk prostate cancer. We examined the extent to which social factors were associated with differences in prostate cancer risk profiles between Black men and NHW men [using a modification to the original D'Amico risk groups based on prostate specific antigen (PSA), Gleason score (GS), and TNM stage (stage)], based on individual and combined clinicopathologic characteristics.

METHODS

We conducted a cross-sectional population-based study of 23,555 Black men and 146,889 NHW men diagnosed with prostate cancer in the California Cancer Registry from 2004 to 2017. We conducted multivariable logistic regression to examine the association of year of diagnosis, block group-level neighborhood socioeconomic status (nSES), marital status, and insurance type on differences in prostate cancer risk profiles between Black and NHW men.

RESULTS

High PSA (>20 ng/mL), GS, stage, individually and combined prostate cancer risk profiles were more common among Black men versus NHW men. In fully adjusted models, relative to NHW men, we observed a persistent 67% increased odds of high PSA among Black men. nSES was the factor most strongly associated with racial disparity in high PSA, accounting for 25% of the difference. Marital status was the factor that was second most associated with a racial disparity.

CONCLUSIONS

nSES was the factor most strongly associated with racial disparities in high PSA prostate cancer.

IMPACT

The influence of nSES on racial disparities in PSA, GS, stage, and prostate cancer risk profiles warrants further consideration.

Recommendations on the diagnosis, treatment and monitoring of testosterone deficiency in men

The relative proportional increase of the elderly population within many countries will become one of the most significant social transformations of the twenty-first century and, for the first time in history, persons aged 65 or above outnumbered children under five years of age globally. One in four persons living in Europe and Northern America will be aged 65 or over. One of the goals of ISSAM is to raise awareness of the special health needs of older men. Since a significant number of aging men will eventually become testosterone deficient, the Hypogonadism panel of ISSAM updates its guidelines.

The Role and Significance of Bioumoral Markers in Prostate Cancer

The prostate is one of the most clinically accessible internal organs of the genitourinary tract in men. For decades, the only method of screening for prostate cancer (PCa) has been digital rectal examination of 1990s significantly increased the incidence and prevalence of PCa and consequently the morbidity and mortality associated with this disease. In addition, the different types of oncology treatment methods have been linked to specific complications and side effects, which would affect the patient's quality of life. In the first two decades of the 21st century, over-detection and over-treatment of PCa patients has generated enormous costs for health systems, especially in Europe and the United States. The Prostate Specific Antigen (PSA) is still the most common and accessible screening blood test for PCa, but with low sensibility and specificity at lower values (<10 ng/mL). Therefore, in order to avoid unnecessary biopsies, several screening tests (blood, urine, or genetic) have been developed. This review analyzes the most used bioumoral markers for PCa screening and also those that could predict the evolution of metastases of patients diagnosed with PCa.

Tissue- and Liquid-Based Biomarkers in Prostate Cancer Precision Medicine

Worldwide, prostate cancer (PC) is the second-most-frequently diagnosed male cancer and the fifth-most-common cause of all cancer-related deaths. Suspicion of PC in a patient is largely based upon clinical signs and the use of prostate-specific antigen (PSA) levels. Although PSA levels have been criticised for a lack of specificity, leading to PC over-diagnosis, it is still the most commonly used biomarker in PC management. Unfortunately, PC is extremely heterogeneous, and it can be difficult to stratify patients whose tumours are unlikely to progress from those that are aggressive and require treatment intensification. Although PC-specific biomarker research has previously focused on disease diagnosis, there is an unmet clinical need for novel prognostic, predictive and treatment response biomarkers that can be used to provide a precision medicine approach to PC management. In particular, the identification of biomarkers at the time of screening/diagnosis that can provide an indication of disease aggressiveness is perhaps the greatest current unmet clinical need in PC management. Largely through advances in genomic and proteomic techniques, exciting pre-clinical and clinical research is continuing to identify potential tissue, blood and urine-based PC-specific biomarkers that may in the future supplement or replace current standard practices. In this review, we describe how PC-specific biomarker research is progressing, including the evolution of PSA-based tests and those novel assays that have gained clinical approval. We also describe alternative diagnostic biomarkers to PSA, in addition to biomarkers that can predict PC aggressiveness and biomarkers that can predict response to certain therapies. We believe that novel biomarker research has the potential to make significant improvements to the clinical management of this disease in the near future.

Active Surveillance in Prostate Cancer: Role of Available Biomarkers in Daily Practice

Prostate cancer (PCa) is the most commonly diagnosed cancer in men. The diagnosis is currently based on PSA levels, which are associated with overdiagnosis and overtreatment. Moreover, most PCas are localized tumours; hence, many patients with low-/very low-risk PCa could benefit from active surveillance (AS) programs instead of more aggressive, active treatments. Heterogeneity within inclusion criteria and follow-up strategies are the main controversial issues that AS presently faces. Many biomarkers are currently under investigation in this setting; however, none has yet demonstrated enough diagnostic ability as an independent predictor of pathological or clinical progression. This work aims to review the currently available literature on tissue, blood and urine biomarkers validated in clinical practice for the management of AS patients.

[Intelligent early prostate cancer detection in 2021: more benefit than harm]

Prostate-specific antigen (PSA) is used for early detection of prostate cancer which represents the most frequent cancer diagnosed in men in Germany and Europe. Results of the largest screening trials revealed that PSA testing reduces the incidence of locally advanced and metastatic prostate cancer and shows an effect on cancer-specific mortality. However, since early diagnosis also results in overdiagnosis and overtreatment of insignificant cancers with associated morbidities, there is a need for a more individualized and risk-tailored modern strategy. The PSA at baseline is an important part of this strategy although the German Federal Joint Committee declined its financial coverage by health insurances. Available validated instruments should accompany the baseline PSA to optimize detection of clinically significant prostate cancer.

The Association between Prostate-Specific Antigen Velocity (PSAV), Value and Acceleration, and of the Free PSA/Total PSA Index or Ratio, with Prostate Conditions

Introduction: Prostate-specific antigen velocity (PSAV) is used to monitor men with clinical suspicion of prostate cancer (PCa), with a normal cut-off point of 0.3–0.5 ng/mL/year. The aim of the study is to establish the predictive capacity of PSAV (value and acceleration) and of the free PSA/total PSA index or ratio. Method: Prospective multicentre observational study in 2035 men of over 47 years of age. Inclusion criteria: men who wished to be informed on the health of their prostate. Exclusion criteria: men with a previously diagnosed prostate condition. Groups: GA: (n = 518): men with serum PSA equal to or greater than 2.01 ng/mL. GB: (n = 775): men with serum PSA greater than or equal to 0.78 ng/mL and less than 2.01 ng/mL. GC: (n = 742): men with serum PSA less than 0.78 ng/mL. Variables: prostate-specific antigen (PSA); age; body mass index (BMI); PSA velocity (PSAV) (ng/mL per year); free PSA/total PSA index (iPSA); PSAV acceleration (increasing: positive, or decreasing: negative); prostate diagnosis (benign prostatic hyperplasia (BPH), prostatic intraepithelial neoplasia (PIN), or infectious and non-infectious prostatitis and prostatic adenocarcinoma (PCa)); de novo diagnoses of urinary tract diseases or conditions; concomitant treatments, diseases and conditions; final diagnosis of prostate health. Results: Mean age 62.35 years (SD 8.12), median 61 (47–94); age was lowest in GC. Mean BMI was 27.89 kg/m² (SD 3.96), median 27.58 (18.56–57.13); no differences between groups. Mean PSAV was 0.69, SD 2.16, median 0.13 (0.001–34.46); PSAV was lowest in GC. Mean iPSA was 27.39 u/L (SD 14.25), median 24.29 (3.7–115); iPSA was lowest in GA. PSAV had more positive acceleration in GA and more negative acceleration in GC. There were 1600 (78.62%) cases of normal prostate or BPH, 322 (15.82%) cases of PIN or non-infectious prostatitis, and 113 (5.55%) cases of PCa. There were more cases of BPH in GC and more cases of PIN or prostatitis and cancer in GA (p = 0.00001). De novo diagnoses: 15 cases of urinary incontinence (UI), 16 discomfort/pain in LUT, 112 cases of voiding disorders, 12 urethral strictures, 19 hematuria, 51 cystitis, 3 pyelonephritis, 4 pelvic inflammatory disease; no differences were found between groups. In the multivariate analysis, PSAV and the direction of PSAV acceleration (positive or negative) were the variables which were correlated most strongly with prostate health. iPSA was associated with the presence of prostatitis, PCa, and BPH. Men in GA had more prostatitis, PCa, treatment with alpha blockers, and history of previous smoking. GB had more cases of BPH and more positive acceleration of PSAV. GC had more normal prostates, more BPH, more use of ranitidine, and more PSAV with negative acceleration. Conclusions: PSAV, direction of PSAV acceleration, and iPSA in PSA cut-off points of 0.78 ng/mL and 2.01 ng/mL in a priori healthy men over 47 predict the probability of benign or malignant pathology of the prostate.

Tobacco and marijuana use and their association with serum prostate-specific antigen levels among African American men in Chicago

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AA men are under-represented in PSA research, a biomarker of prostate cancer aggresiveness.

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Cigarette smoking was associated with an increase in PSA among older AA men.

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Tobacco use was associated with an increase in PSA among older AA men.

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Marijuana use was associated with a decrease in PSA among older AA men.

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Future behavioral risk factor studies linked to biopsy outcomes are warranted.

African American (AA) men experience more than twice the prostate cancer mortality as White men yet are under-represented in academic research involving prostate-specific antigen (PSA), a biomarker of prostate cancer aggressiveness. We examined the impact of self-reported tobacco (cigarette pack-years and current tobacco use including e-cigarettes) and current regular marijuana use on serum PSA level based on clinical laboratory testing among 928 AA men interviewed 2013–2018 in Chicago. We defined outcome of elevated PSA ≥ 4.0 ng/mL for logistic regression models and continuous PSA increases for general linear models. All models were adjusted for age, sociodemographic characteristics, healthcare utilization, body mass index, and self-reported health. Among 431 AA men age ≥ 55 years, we observed ∼ 5 times the odds of elevated PSA among those with > 1 pack-years of cigarette smoking vs. never-smokers (odds ratio [OR] = 5.09; 95% confidence interval [CI] = 1.57–16.6) and a quarter the odds of elevated PSA among current marijuana users vs. non-users (OR = 0.27; 95% CI = 0.08–0.96). PSA increased on average 1.20 ng/mL among other current tobacco users vs. non-users. Among older AA men, cigarette smoking history and current tobacco use were positively associated with an increase in PSA levels and current marijuana use were inversely associated with PSA levels. Future work with studies of diverse patient populations with cancer outcomes are needed to assess whether these behavioral characteristics contribute to racial/ ethnic disparities in prostate cancer outcomes. Our study provides novel evidence regarding potential differences in PSA levels among older AA men according to behavioral characteristics.

Biomarkers in the setting of benign prostatic hyperplasia-induced lower urinary tract symptoms: what an interventional radiologist needs to know

With increasing evidence to support prostate artery embolization (PAE) in the treatment of benign prostatic hyperplasia (BPH)-induced lower urinary tract symptoms (LUTS), Interventional Radiologists have begun to play an important role in the management of these patients. One area of knowledge needed when developing a PAE practice is knowledge of prostate-specific antigen (PSA) and other biomarkers utilized to detect prostate cancer in this population and what role they should play in the work up and follow-up of patients presenting with presumed BPH-induced LUTS. Furthermore, understanding how to evaluate presumed BPH-induced LUTS and stratify the risk of prostate cancer is an important skill to develop. The goal of this review is to provide Interventional Radiologists who have begun or aim to begin a PAE practice with the information they need to know regarding PSA levels and prostate cancer risk stratification for this patient population.

Prostate MRI with PI-RADS v2.1: initial detection and active surveillance

The role of prostate MRI in clinical practice has continued to broaden over time. Multiple iterations of PI-RADS reporting have aided in improving detection and reporting of prostate cancer. In addition, recent recommendations from the PI-RADS Steering Committee promote an MRI-first approach with an MRI-directed prostate cancer diagnostic pathway. It is imperative for radiologists to be knowledgeable and familiar with prostate MRI and PI-RADS recommendations, as there is an increasing demand for prostate imaging by clinicians and patients alike.

A Pilot retrospective analysis of alpha-blockers on recurrence in men with localised prostate cancer treated with radiotherapy

While alpha-blockers are commonly used to reduce lower urinary tract symptoms in prostate cancer patients receiving radiotherapy, their impact on response to radiotherapy remains unknown. Therefore, this pilot study aimed to retrospectively determine if alpha-blockers use, influenced response to radiotherapy for localised prostate cancer. In total, 303 prostate cancer patients were included, consisting of 84 control (alpha-blocker naïve), 72 tamsulosin and 147 prazosin patients. The main outcomes measured were relapse rates (%), time to biochemical relapse (months) and PSA velocity (ng/mL/year). Recurrence free survival was calculated using Kaplan-Meier analysis. Prazosin significantly reduced biochemical relapse at both two and five-years (2.72%, 8.84%) compared to control (22.61%, 34.52%). Recurrence free survival was also significantly higher in the prazosin group. This remained after multivariable analysis (HR: 0.09, 95% CI: 0.04-0.26, p < 0.001). Patients receiving prazosin had a 3.9 times lower relative risk of biochemical relapse compared to control. Although not statistically significant, tamsulosin and prazosin extended recurrence free survival by 13.15 and 9.21 months respectively. We show for the first time that prazosin may reduce risk of prostate cancer recurrence and delay time to biochemical relapse and provides justification for prospective studies to examine its potential as an adjunct treatment option for localised prostate cancer.

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.

Detection of Prostate Cancer Antigen 3 and Prostate Cancer Susceptibility Candidate in Non-DRE Urine Improves Diagnosis of Prostate Cancer in Chinese Population

Although prostate biopsy is the gold standard for the diagnosis of prostate cancer, it also leads to high incidence of negative biopsies and the diagnosis of clinically low-risk prostate cancer and the subsequent overtreatment. It remains an unmet need to discover new biomarkers in order to defer the unnecessary biopsies in clinical practice. In this study, we described a new method, LBXexo score, to measure the urine exosomal PCA3/PRAC expression from non-DRE urine as a noninvasive diagnosis to improve the detection rate in Chinese population with a low serum PSA level. First-voided urine samples were collected to isolate exosomes, and exosomal RNAs of PCA3 and PRAC were measured by quantitative reverse transcription PCR. A significant increase in exoPCA3/PRAC was observed in both any-grade and high-grade prostate cancer groups when compared with the biopsy-negative group. Receiver-operating characteristic curve analyses showed that the LBXexo score significantly improved diagnostic performance in predicting biopsy results, with AUCs of 0.723 (p=0.017) and 0.736 (p=0.038) for any-grade and high-grade (GS ≥ 7) prostate cancer, respectively. For high-grade cancer, LBXexo had the negative and positive predictive values of 100% and 27.59%, respectively, and could potentially avoid unnecessary biopsy. This is the first report in Chinese population that demonstrates the predictive value of the exosomal expression of PCA3 and PRAC derived from non-DRE urine in predicting prostate biopsy outcomes. It could be used in clinical practice to make a better informed biopsy decision and avoid unnecessary biopsies in Chinese population.

Use of radiobiology in medical jurisprudence, with particular reference to delays in diagnosis and therapeutic onset

OBJECTIVE

This paper considers aspects of radiobiology and cell and tissue kinetics applicable to legal disputations concerned with diagnostic and treatment onset delays.

METHODS

Various models for tumour volume changes with time are reviewed for estimating volume ranges at earlier times, using ranges of kinetic parameters. Statistical cure probability methods, using Poisson statistics with allowances for parameter heterogeneity, are also described to estimate the significance of treatment delays, as well as biological effective dose (BED) estimations of radiation effectiveness.

RESULTS

The use of growth curves, based on parameters in the literature but with extended ranges, can identify a window of earlier times when such tumour volumes would be amenable to a cure based on the literature for curability with stage (and dimensions). Also, where tumour dimensions are not available in a post-operative setting, higher cure probabilities can be achieved if treatment had been given at earlier times.

CONCLUSION

The use of radiobiological modelling can provide useful insights, with quantitative assessments of probable prior conditions and future outcomes, and thus be of assistance to a Court in deciding the most correct judgement.

ADVANCES IN KNOWLEDGE

This study collates prior knowledge about aspects of radiobiology that can be useful in the accumulation of sufficient proof within medicolegal claims involving diagnostic and treatment days.

Landmarks in prostate cancer

The field of prostate cancer has been the subject of extensive research that has resulted in important discoveries and shaped our appreciation of this disease and its management. Advances in our understanding of the epidemiology, natural history, anatomy, detection, diagnosis, grading, staging, imaging, and management of prostate cancer have changed clinical practice and influenced guideline recommendations. The development of the Gleason score and subsequent modifications enabled accurate prediction of prognosis. Increased anatomical understanding and improved surgical techniques resulted in the development of nerve-sparing surgery for radical prostatectomy. The advent of active surveillance has changed the management of low-risk disease, and chemotherapy and hormonal therapy have improved the outcomes of patients with distant disease. Ongoing research and clinical trials are expected to yield more practice-changing results in the near future.

Effect of Prior Local Treatment and Prostate-Specific Antigen Kinetics during Androgen-Deprivation Therapy on the Survival of Castration-Resistant Prostate Cancer

Prostate-specific antigen (PSA) kinetics predicts survival in castration-resistant prostate cancer (CRPC); however, the influence of prior treatment on this relationship is unclear. Patients with CRPC were stratified according to time to PSA nadir and time to CRPC progression to investigate their prognostic significance on prostate cancer-specific survival (PCSS) and whether PSA kinetics may serve as prognosticators regardless of prior local treatment. This multicenter retrospective study included 295 patients diagnosed with CRPC between September 2009 and November 2017. PSA kinetics during androgen-deprivation therapy (ADT) including %PSA decline, PSA nadir level, time to PSA nadir, and time to CRPC progression was investigated. Subgroup analysis was performed according to the prior history of local curative treatment. Patients who did not receive prior local treatment with ≥6 months to PSA nadir and <12 months to CRPC, showed lower PCSS rates than those with <6 months to PSA nadir (23.3% vs. 45.3%; p = 0.031) and ≥12 months to CRPC (20.0% vs. 47.8%; p = 0.001). In patients who had received local treatment, PSA kinetic parameters did not influence PCSS. Our results indicate that time to PSA nadir and time to CRPC progression are prognosticators of PCSS in patients with CRPC who did not previously receive curative local treatment.

A different perspective: Can urine pH be important in the diagnosis of prostate cancer?

OBJECTIVE

The aim of our study was to investigate emphasis of urinary pH in patients with prostate cancer.

METHODS

Patients, who underwent 12-core prostate biopsy because of prostate-specific antigen elevation and suspicious digital rectal examination, were retrospectively reviewed. According to pathology, patients with prostate cancer were classified as group 1, and patients with benign prostatic hyperplasia were classified as group 2. Primary endpoint of this study was the urine pH. The age of two groups and urine pH were compared with each other. Student t test and Mann-Whitney U test were used for the intergroup analysis of continuous variables. A cut-off value for urine pH was determined with a receiver operating characteristic curve. p < 0.05 was considered as statistically significant.

RESULTS

There were 119 patients in group 1 and 99 patients in group 2. When urine pHs of both groups were compared, group 1 and group 2 were 5.1 ± 0.45 and 5.5 ± 0.79, respectively (p = 0.0001). The cut-off value determined by receiver operating characteristic curve analysis for urine pH was 5.2 (sensitivity: 42%, specificity: 79%, area under the curve: 0.61; 95% CI: [0.53, 0.68]; p = 0.003).

CONCLUSION

Acidic urine pH may be important for predicting prostate cancer according to this study.

An Ultra-Rapid Biosensory Point-of-Care (POC) Assay for Prostate-Specific Antigen (PSA) Detection in Human Serum

Prostate-specific antigen (PSA) is the established routine screening tool for the detection of early-stage prostate cancer. Given the laboratory-centric nature of the process, the development of a portable, ultra rapid high-throughput system for PSA screening is highly desirable. In this study, an advancedpoint-of-care system for PSA detection in human serum was developed based on a cellular biosensor where the cell membrane was modified by electroinserting a specific antibody against PSA. Thirty nine human serum samples were used for validation of this biosensory system for PSA detection. Samples were analyzed in parallel with a standard immunoradiometric assay (IRMA) and an established electrochemical immunoassay was used for comparison purposes. They were classified in three different PSA concentration ranges (0, <4 and ≥4 ng/mL). Cells membrane-engineered with 0.25 μg/mL anti-PSA antibody demonstrated a statistically lower response against the upper (≥4 ng/mL) PSA concentration range. In addition, the cell-based biosensor performed better than the immunosensor in terms of sensitivity and resolution against positive samples containing <4 ng/mL PSA. In spite of its preliminary, proof-of-concept stage of development, the cell-based biosensor could be used as aninitiative for the development of a fast, low-cost, and high-throughput POC screening system for PSA.

Liquid Biopsy Potential Biomarkers in Prostate Cancer

Prostate cancer (PCa) is the second most common cancer in men worldwide with an incidence of 14.8% and a mortality of 6.6%. Shortcomings in comprehensive medical check-ups in low- and middle-income countries lead to delayed detection of PCa and are causative of high numbers of advanced PCa cases at first diagnosis. The performance of available biomarkers is still insufficient and limited applicability, including logistical and financial burdens, impedes comprehensive implementation into health care systems. There is broad agreement on the need of new biomarkers to improve (i) early detection of PCa, (ii) risk stratification, (iii) prognosis, and (iv) treatment monitoring. This review focuses on liquid biopsy tests distinguishing high-grade significant (Gleason score (GS) ≥ 7) from low-grade indolent PCa. Available biomarkers still lack performance in risk stratification of biopsy naïve patients. However, biomarkers with highly negative predictive values may help to reduce unnecessary biopsies. Risk calculators using integrative scoring systems clearly improve decision-making for invasive prostate biopsy. Emerging biomarkers have the potential to substitute PSA and improve the overall performance of risk calculators. Until then, PSA should be used and may be replaced whenever enough evidence has accumulated for better performance of a new biomarker.

Prostate-Specific Antigen Trends Predict the Probability of Prostate Cancer in a Very Large U.S. Veterans Affairs Cohort

If prostate-specific antigen (PSA) trends help identify elevated prostate cancer (PCa) risk, they might provide early warning of progressing cancer for further evaluation and justify annual testing. Our objective was to determine whether PSA trends predict PCa likelihood. A biopsy cohort of 361,657 men was obtained from a Veterans Affairs database (1999–2012). PSA trends were estimated for the 310,458 men with at least 2 PSA tests prior to biopsy. Cancer tumors may grow exponentially with cells doubling periodically. We hypothesized that PSA from prostate cancer grows exponentially above a no cancer baseline. We estimated PSA trends on that basis along with five descriptive variables: last PSA before biopsy, growth rate in PSA from cancer above a baseline, PSA variability around the trend, number of PSA tests, and time span of tests. PSA variability is a new variable that measures percentage deviations of PSA tests from estimated trends with 0% variability for a smoothly increasing trend. Logistic regression models were used to estimate relationships between the probability of PCa at biopsy and the trend variables and age. All five PSA trend variables and age were significant predictors of prostate cancer at biopsy (p < 0.0001). An overall logistic regression model achieved an AUC of 0.67 for men with at least 4 tests over at least 3 years, which was a substantial improvement over a single PSA (AUC 0.58). High probability of PCa was associated with low PSA variability (smooth trends), high PSA, high growth rate, many tests over a long time-span and older age. For example, at 4.0 PSA the probability of cancer is 32% for 1 PSA test and increases to 68% for 8 tests over 7 years with smooth, fast growth (0% variability and 50% exponential growth). Our results show that smooth, fast exponential growth in PSA above a baseline predicts an increased probability of PCa. The probability increases as smooth (low variability) trends are observed for more tests over a longer time span, which makes annual testing worth considering. Worrisome PSA trends might be used to trigger further evaluation and continued monitoring of the trends—even at low PSA levels.

Clean Colorectum at Diagnostic Colonoscopy: Subsequent Detection of Extracolonic Malignancies by Plasma Protein Biomarkers?

Introduction

Most of the subjects undergoing diagnostic colonoscopy do not have neoplastic bowel lesions. Potentially, some of the symptoms may therefore be caused by extracolonic malignancy, and subjects with persisting symptoms may need subsequent examinations. Blood-based, cancer-associated biomarkers may aid in directing the examinations for other specific malignant diseases.

Methods

EDTA plasma samples available from a previous prospective study of subjects undergoing diagnostic colonoscopy were used for analysis of 18 protein biomarkers. The study population of 3732 subjects included 400 patients with colorectal cancer (CRC) and 177 patients with extracolonic malignancies. Univariable analysis of the association of specific biomarkers and extracolonic cancers included those with 10 or more cases. Subsequently, reduced models of 4 or 6 biomarkers, respectively, were established by choosing those with the highest likelihood; age and sex were included as well.

Results

Univariable analyses showed that CyFra21-1 had an area under curve (AUC) of 0.87 for lung cancers (n = 33), CA19-9 had an AUC of 0.85 for pancreatic cancer (n = 22), CA125 had an AUC of 0.95 for ovary cancer (n = 16), B2M had an AUC of 0.81 for non-Hodgkin lymphoma (n = 12), and total prostate-specific antigen had an AUC of 0.99 for prostate cancer (n = 10). The multivariable analysis of 4 or 6 biomarkers plus age and sex as explanatory variables showed AUCs of 0.82 to 0.85 both for extracolonic cancers and CRC. The 4 biomarkers included in the model for detection of extracolonic cancers were CA125, hsCRP, CA19-9, and CyFra21-1; the 2 additional for the 6 biomarkers model were CEA and Galectin-3. Similarly, the 4 biomarkers included in the model for detection of CRC were CEA, CyFra21-1, Ferritin, and HE4; the two additional for the 6 biomarkers model were hsCRP and Pepsinogen 2.

Conclusions

Results of this study indicate that it may be possible to detect subjects that have an increased risk of extracolonic cancer following a colonoscopy without findings of neoplastic lesions. Combinations of various protein biomarkers may direct subsequent examination after colonoscopy with clean colorectum. The results, although preliminary, may form the basis for additional research directed both for primary examinations of subjects with symptoms of malignancy and subsequent examinations after colonoscopy.

Preliminary Results of Clinical Evaluation of the Free/Total Prostate-Specific Antigen Ratio in a Multicentric Study

Aims and Background

The free/total (F/T) prostate-specific antigen (PSA) ratio is probably the most promising tool proposed to increase the specificity of PSA in the diagnosis of prostate cancer. The aim of the present study was to evaluate the clinical value of the F/T ratio in 138 patients with benign hyperplasia, 101 with untreated prostate cancer, and 176 apparently healthy men.

Methods

We used a new immunometric assay of free PSA (FPSA-RIACT, CIS Diagnostici, Italy) which has shown good analytical performance; sample handling and storage under routine conditions did not affect the antigen stability.

Results

The diagnostic efficiency of the F/T ratio was significantly better than that of total PSA. In patients with total PSA ranging from 4 to 10 ng/ml, at a specificity level of 95% total PSA showed a sensitivity of 7%, whereas the sensitivity of F/T increased to 70%. Using the F/T ratio as a decision tool in association with total PSA and considering all cases candidate to biopsy (total PSA greater than 3.79 ng/ml corresponding to the 95% level), we demonstrated a 35% reduction of total biopsies that would have been required on the basis of total PSA alone.

Conclusions

The determination of the percentage of F/T serum PSA significantly improves the specificity of the marker, particularly in the 4-10 ng/ml dose range where unnecessary prostate biopsies can be reduced.

Free to Total Psa Ratio is not a Reliable Predictor of Prostate Biopsy Outcome

Aims and background

The aim of this study was to assess the validity of predictors of prostate biopsy outcome in order to improve their positive predictive value.

Material and methods

The study material consisted of a consecutive series of 410 prostate biopsies performed during 2003. The variables tested as possible predictors were age, findings at palpation (DRE) and ultrasonography (TRUS), total prostate-specific antigen (PSA), and free-to-total prostate-specific antigen (F/T) ratio. The association with biopsy outcome (cancer vs non-cancer) was investigated by univariate and multivariate analysis.

Results

All tested variables showed a statistically significant and independent association with biopsy outcome both in univariate and multivariate analysis. Nevertheless, no variable had good performance as a biopsy indicator: depending on the considered variable, three to nine cancer biopsies would be delayed in order to avoid ten benign biopsies. Using 0.12, 0.15 and 0.20 as the cutoff for F/T would avoid 77.3%, 64.4% and 43.1% of benign biopsies but would delay 54.0%, 35.6% and 21.0% of cancer biopsies, respectively.

Conclusion

Although it may contribute to diagnostic suspicion, F/T should never exclude a biopsy indicated because of suspicion arising from other diagnostic tests.

Innovative Diagnostic Methods for Early Prostate Cancer Detection through Urine Analysis: A Review

Prostate cancer is the second most common cause of cancer death among men. It is an asymptomatic and slow growing tumour, which starts occurring in young men, but can be detected only around the age of 40&ndash;50. Although its long latency period and potential curability make prostate cancer a perfect candidate for screening programs, the current procedure lacks in specificity. Researchers are rising to the challenge of developing innovative tools able of detecting the disease during its early stage that is the most curable. In recent years, the interest in characterisation of biological fluids aimed at the identification of tumour-specific compounds has increased significantly, since cell neoplastic transformation causes metabolic alterations leading to volatile organic compounds release. In the scientific literature, different approaches have been proposed. Many studies focus on the identification of a cancer-characteristic &ldquo;odour fingerprint&rdquo; emanated from biological samples through the application of sensorial or senso-instrumental analyses, others suggest a chemical characterisation of biological fluids with the aim of identifying prostate cancer (PCa)-specific biomarkers. This paper focuses on the review of literary studies in the field of prostate cancer diagnosis, in order to provide an overview of innovative methods based on the analysis of urine, thereby comparing them with the traditional diagnostic procedures.

Third-Generation Psa: Ultrasensitive or Ultraprecise Assay?

The ultrasensitive PSA assay has been recently acknowledged as a useful tool for the monitoring of patients prostatectomized for prostatic cancer. We have evaluated a commercially available ultrasensitive PSA assay (Immulite Third Generation PSA - DPC - Los Angeles CA) in comparison with the routinely used PSA (Immulite PSA - DPC - Los Angeles CA). When evaluated with different approaches, the analytical sensitivity of ultrasensitive PSA ranged between 0.0029 and 0.0038 ng/ml. The biological detection limit was 0.0098 ng/ml. Dilution of samples with low PSA levels showed a good recovery (from 88 to 113%) up to 1:128 dilution factor (final PSA levels ranging from 0.004 to 0.016 ng/ml in different samples). The assay precision was excellent in the low dose range, the highest interassay interadjustment CV among replicates being 5.84% when assaying serum samples with PSA lower than 1.0 ng/ml.

Besides its role in the follow-up of prostatectomized patients, the evaluated ultrasensitive PSA could be reliably used for the detection of clinically meaningful PSA variations in the low dose range, and it could therefore be a candidate for the assessment of PSA velocity.

Effect of Age, Family History of Prostate Cancer, Prostate Enlargement and Seasonality on PSA Levels in a Contemporary Cohort of Healthy Italian Subjects

We assessed the joint effect of age at enrolment, age at follow-up, family history of prostate cancer, prostate enlargement and seasonality on prostate-specific antigen (PSA) estimated through log-normal mixed-effects modeling in an Italian cohort of healthy, 45- to 65-year-old subjects over a 4-year period. The median ratio was used as the measure of effect. Median and mean baseline PSA were 0.78 (interquartile range: 0.41–1.50) and 1.27 (95% CI: 1.19–1.35) ng/mL, respectively. A similar median annual increase of 5.7% (95% CI: 4.8%-6.5%) was found for age at enrolment and age at follow-up. Individuals with moderate to severe prostate enlargement had a median PSA ratio of 1.040 (95% CI: 0.919–1.176) and 1.318 (95% CI: 1.128–1.539), respectively. Median ratios of 1.200 (95% CI: 0.026–1.404) and 1.300 (95% CI: 0.915–1.845), respectively, were computed for subjects with only one or more than one prostate-cancer-affected relatives. Regarding seasonality, the highest value was shown in summertime, the lowest in wintertime, and the resulting median ratio was 1.280 (95% CI: 1.117–1.468). Irrespective of age, baseline PSA was in most cases about 1.00 ng/mL with a yearly median variation of about 5% over a 4-year period. Indeed, prostate enlargement, prostate cancer family history and seasonality showed a remarkable impact on PSA measurement. This should be considered when counseling patients with a PSA history.

Serum Tumor Markers: Past, State of the Art, and Future

Serum determinations of tumor markers are indispensable in the diagnosis and management of cancer, and therefore play an important role in clinical practice. After a short historical survey, we systematically review a number of contemporary aspects of serum tumor markers related to various organ systems, and briefly indicate possible future developments.

Predicting Prostate Biopsy Outcome by Findings at Digital Rectal Examination, Transrectal Ultrasonography, PSA, PSA Density and Free-To-Total PSA Ratio in a Population-Based Screening Setting

The study offers a retrospective analysis of the positive predictive value (PPV) of several variables, i.e. digital rectal examination (DRE), transrectal ultrasonography (TRUS), PSA value, PSA density (PSAD), and free/total PSA ratio (F/T), for the histologic outcome of 179 prostate biopsies performed within a population-based screening trial. The ratio of spared benign biopsies to missed cancers (SBB/MC) if biopsy results had been decided on the basis of single variables was also evaluated. PPV was 82.9% for DRE, 56.3% for TRUS, 26.6% for PSA (cutoff ≥4 ng/mL), 47.4% for PSA (cutoff ≥10 ng/mL), 42.0% for PSAD (cutoff 0.15), 59.2% for PSAD (cutoff 0.20), 34.9% for F/T (cutoff 0.20) and 40.0% for F/T (cutoff 0.15). SBB/MC was 121/23 for DRE, 96/12 for TRUS, 11/10 for PSA (cutoff ≥4 ng/mL), 107/34 for PSA (cutoff ≥10 ng/mL), 87/23 for PSAD (cutoff 0.15), 109/26 for PSAD (cutoff 0.20), 45/8 for F/T (cutoff 0.20) and 70/14 for F/T (cutoff 0.15). Multivariate analysis of the association with biopsy outcome showed the highest odds ratio for TRUS (13.24, 95% CI=4.4–30.7), and considerably lower values for DRE (4.17, 95% CI=2.0–8–9), PSAD (cutoff 0.20: 3.24, 95% CI=–1.8–5.7) and F/T (cutoff <0.15: 3.16, 95% CI =1.7–1.8). None of the possible variable combinations was clinically useful: the highest PPV (83.3%) was obtained with a combination of suspicious DRE/TRUS, PSAD >0.20 and F/T <0.15, which nevertheless missed 20 of 52 cancers.

Prostate Cancer Screening

During the prostate-specific antigen-based prostate cancer (PCa) screening era there has been a 53% decrease in the US PCa mortality rate. Concerns about overdiagnosis and overtreatment combined with misinterpretation of clinical trial data led to a recommendation against PCa screening, resulting in a subsequent reversion to more high-risk disease at diagnosis. Re-evaluation of trial data and increasing acceptance of active surveillance led to a new draft recommendation for shared decision making for men aged 55 to 69 years old. Further consideration is needed for more intensive screening in men with high-risk factors. PCa screening significantly reduces PCa morbidity and mortality.

Analysis of PSA Velocity in 1666 Healthy Subjects Undergoing Total PSA Determination at Two Consecutive Screening Rounds

The study purpose was to assess PSA velocity (PSAV) in healthy subjects in order to establish a reliable cutoff for the differential diagnosis of prostate cancer in a screening setting. We studied a series of 1666 healthy men aged 55 to 74 years undergoing two total PSA determinations at a four-year interval within a population-based randomized screening trial at the Centro per lo Studio e la Prevenzione Oncologica of Florence. First and second screening round PSA assays (PSA1 and PSA2) were carried out with the same method and by the same laboratory. PSAV (PSA1–PSA2/year) was determined in non-cancer subjects in the overall series or in specific age and PSA subgroups, and in subjects with cancer detected at the second screening round. Average PSAV in 1648 non-cancer subjects was 0.07 ng/mL/year (range −2.18+5.99, 95% CI 0.05–0.09); at least one third of subjects showed a decrease in PSA (negative PSAV), mostly of limited magnitude and in the low PSA range. Average PSAV in the 18 cancer patients was 1.16 ng/mL/year (range 0.10–5.6, 95% CI 0.56–1.77), which is significantly higher (p<0.01) than in non-cancer subjects. None of the cancer patients showed a PSA decrease over time. Whatever cutoff was taken for PSAV, its power to discriminate cancer was limited: in particular the previously used PSAV cutoff of 0.75 ng/mL/year would have included only 42 of the 1648 non-cancer subjects (specificity 97.5%) but excluded eight of the 18 cancer patients (sensitivity 55.5%). At best, with the adopted screening protocol PSAV (cutoff 0.10 ng/mL/year) could have spared 27.9% of non-cancer subjects with PSA ≥2.5 ng/mL further diagnostic assessment and 22.7% of non-cancer subjects with PSA ≥4 ng/mL random sextant biopsy, while missing no cancers. This study provides a reliable estimate of PSAV based on a large unbiased population sample. PSAV is widely variable over time, particularly at low PSA values. PSAV might be of value as an indicator for diagnostic assessment and random sextant biopsy in a screening setting.

On the Clinical Usefulness of the Free-to-Total Prostate-Specific Antigen Ratio

The free-to-total prostate-specific antigen ratio (F/T PSA) is associated with the presence of prostate cancer and is thus used as an indicator for suspicion of prostate cancer and as a determinant for biopsy. We reviewed a recent retrospective series of 966 consecutive prostate biopsies where F/T PSA was blindly determined and did not influence biopsy indication. We simulated the association of F/T PSA with biopsy outcome and its impact as a biopsy determinant. When adopting an F/T PSA cutoff of 10%, 13%, 16% or 20% among random sextant biopsies in the 4–10 ng/mL total PSA range, the sensitivity was 15%, 37%, 55% and 72% and the specificity 89%, 80%, 64% and 44%, respectively. Using F/T PSA as a biopsy determinant, from 1.7 to 2.6 cancer biopsies would have been delayed to avoid 10 benign biopsies. As this balance is not acceptable, F/T PSA has no role as a biopsy indicator and its clinical use is questionable.

PSA Doubling Time as a Predictor of the Outcome of Random Prostate Biopsies Prompted by Isolated PSA Elevation in Subjects Referred to an Outpatient Biopsy Facility in a Routine Clinical Scenario

Aim

To assess the validity of PSA doubling time (PSADT) as a predictor of prostate sextant biopsy outcome in patients with PSA levels in the 4–10 ng/mL range.

Material and methods

A consecutive series of 355 sextant biopsies performed during 2001–2007 in subjects with negative digital rectal examination and transrectal ultrasonography was considered. Variables tested as possible predictors were age, total and free/total PSA value, PSA velocity and PSA doubling time. While PSA at time of biopsy and free/total PSA were determined with a standardized method undergoing strict quality control, previous PSA values used to assess velocity/doubling time came from other labs using different assays over widely varying intervals of time. The association with biopsy outcome (cancer vs non-cancer) was investigated by univariate and multivariate analysis.

Results

Apart from free/total PSA ratio, no other studied variable showed a statistically significant and independent association with biopsy outcome, either at univariate or multivariate analysis. No studied variable had a good performance as a biopsy indicator. Depending on the variable considered, 1.17 to 1.97 cancers would be missed to spare 10 benign biopsies.

Conclusion

When based on PSA data determined with different assays over widely varying intervals and in the absence of an underlying protocol for PSA surveillance, PSA velocity and doubling time should never discount a biopsy prompted by total PSA elevation.

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.

Trajectories of prostate-specific antigen after treatment for prostate cancer

Prostate-specific antigen (PSA) measurements after primary treatment reflect residual tumor burden among men with prostate cancer. Using a mixture model analysis, we identified distinct trajectories of post-treatment PSA measurements and evaluated their associations with prostate cancer mortality. The study sample included 623 US Veterans treated for prostate cancer with curative intent during 1991-1995; 225 men received surgery and 398 men received radiation therapy. Post-treatment PSA measurements over a 2-year period for each patient were evaluated in latent class mixture models using the SAS TRAJ procedure, and groups of men with distinct trajectories of PSA were identified. These groups were then assessed for associations with 10-year prostate cancer mortality using proportional hazards analysis. Analyses identified three distinct groups-representing patterns of both initial values and changes in PSA over time-after surgery (n=172/31/14) and radiation therapy (n=253/103/22). Men in groups with patterns of higher (compared with the group with lowest) PSA values tended to have worse survival experience: HRs for prostate cancer mortality were 3.45 (P=0.18) and 22.7 (P<0.001) for surgery, and 2.70 (P=0.005) and 18.1 (P<0.001) for radiation therapy. The results indicate that PSA measurements after surgery or radiation therapy with curative intent include groups of men with a diverse spectrum of prognosis for prostate cancer mortality. Although contemporary PSA levels are lower than those observed in the study sample, the corresponding trajectory patterns may become evident shortly after the time of diagnosis and treatment.

Biomarkers for Prostate Biopsy and Risk Stratification of Newly Diagnosed Prostate Cancer Patients

INTRODUCTION

Many new markers are now available as an aid for decisions about prostate biopsy for men without prostate cancer, and/or to improve risk stratification for men with newly diagnosed prostate cancer.

METHODS

A literature review was performed on currently available markers for use in decisions about prostate biopsy and initial prostate cancer treatment.

RESULTS

Although total prostate-specific antigen cutoffs were traditionally used for biopsy decisions, PSA elevations are not specific. Repeating the PSA test, and adjusting for factors like age, prostate volume and changes over time can increase specificity for biopsy decisions. The Prostate Health Index (phi) and 4K Score are new PSA-based markers that can be offered as second-line tests to decide on initial or repeat prostate biopsy. The PCA3 urine test and ConfirmMDx tissue test are additional options for repeat biopsy decisions. For men with newly diagnosed prostate cancer, genomic tests are available to refine risk classification and may influence treatment decisions.

CONCLUSIONS

Numerous secondary testing options are now available that can be offered to patients deciding whether to undergo prostate biopsy and those with newly diagnosed prostate cancer.

Diagnosis, staging, and risk stratification in prostate cancer: Utilizing diagnostic tools to avoid unnecessary therapies and side effects

A lack of appropriate diagnostic tools for prostate cancer has led to overdiagnosis and over treatment. In a recent publication in the New England Journal of Medicine, Hamdy et al showed no difference in the outcomes of patients that had undergone either radical prostatectomy, radiotherapy, or active monitoring. In an effort to enhance clinical stratification, the development of improved, more accurate diagnostic tools is actively being pursued. Herein, we explore recent advances in prostate cancer screening, including biomarker assays, genetic testing, and specialized fields, such as mathematical oncology. These newly developed, highly sensitive diagnostic assays may potentially aid clinicians in selecting appropriate therapies for patients in the very near future.