A multicenter study of [-2]pro-prostate specific antigen combined with prostate specific antigen and free prostate specific antigen for prostate cancer detection in the 2.0 to 10.0 ng/ml prostate specific antigen range

Prostate cancer and the role of biomarkers

PURPOSE

To review available prostate cancer biomarkers and their performance in a clinical order, from prostate cancer detection, to treatment of localized and advanced disease.

METHODS

We used an electronic literature search of the PubMed database using the key words "prostate biomarkers," "genomic markers," and "prostate cancer screening," as well as specific biomarkers, until March 2019.

RESULTS

Prostate-specific antigen (PSA) lacks sensitivity for prostate cancer detection, and PSA derivatives have slightly improved its specificity, but have not resolved the limitations of PSA screening. Prostate cancer biomarkers have emerged as an ancillary tool to guide the clinical decision-making in different clinical scenarios. Urine-based tests can identify patients who may benefit from a prostate biopsy, and issue-based markers are helpful in guiding the decision regarding a second biopsy, stratifying patient with newly diagnosed prostate cancer to active surveillance or treatment, and identifying patients who may benefit from adjuvant treatment after surgery.

CONCLUSIONS

New biomarkers have improved risk stratification in diagnosing and treating prostate cancer. Many of these markers are still considered experimental, and their efficacy and cost utility have not been determined.

A prospective study of a urine and plasma biomarker test for the prediction of gleason ≥3 + 4 prostate cancer in a mixed cohort

Purpose: Definitive diagnosis of prostate cancer is based on biopsies, a procedure associated with side-effects. The use of biomarkers in blood and urine could potentially help clinicians select patients for whom biopsies are needed. The aim of the study was to test a new urine and plasma biomarker test in detecting medium and high grade prostate cancer.Materials and methods: Blood and urine samples were prospectively collected from 41 patients prior to prostate biopsy or TUR-P and again after 3 months. The cohort included patients with suspicion of prostate cancer and patients with prior prostate cancer diagnosis. The mRNA expression of ten selected genes measured by PCR were used together with clinical data in multiple algorithms for prediction of medium-high grade prostate cancer in prostate biopsies. The testing was originally developed and validated in the USA. The method was transferred to a local Danish laboratory. Medium and high grade cancer was defined as Gleason score ≥ 3 + 4.Results: Using the biomarker test, prior to any prostate procedures, the sensitivity for detecting medium-high grade prostate cancer was 100% and the specificity was 56% and 63%, depending on the cut-off point used. When using the biomarker test, following biopsy or TUR-P, the sensitivity and specificity were reduced to 89% and 28-34% respectively. When comparing results, there was a significant difference (p < 0.05), favoring the test performed prior to the procedures.Conclusions: We were able to predict the presence of medium-high grade prostate cancer, thereby confirming earlier findings of the biomarker test.

The cost-effectiveness of prostate health index for prostate cancer detection in Chinese men

BACKGROUND

Prostate-specific antigen (PSA) and prostate health index (PHI) have been used as biomarkers for prostate cancer detection. In this study, we aimed to evaluate the cost-effectiveness of PHI for prostate cancer detection in Chinese men.

METHOD

We developed a Markov model for Chinese male patient aged 50-75 years old. The PSA strategy was to offer TRUS-PB for all patients with elevated PSA of 4-10 ng/mL. The PHI strategy was to offer PHI for patients with elevated PSA of 4-10 ng/mL. TRUS-PB would only be offered for patients with PHI >35.0. Model inputs were extracted from local data when available. The cost per quality-adjusted life years gained for both strategies were calculated. The incremental cost-effectiveness ratios in relation to the willingness-to-pay (WTP) threshold were compared. One-way sensitivity analysis and probabilistic sensitivity analysis were performed. Cost-effectiveness acceptability curves were also constructed.

RESULTS

With a Markov model of 25 screening cycles from age 50 to 75 years, the mean total costs per man were estimated to be USD 27,439 in the PSA strategy and USD 22,877 in the PHI strategy. The estimated effects were estimated to be 15.70 in the PSA strategy and 16.05 in the PHI strategy. The PHI strategy was associated with an expected decrease in cost of USD 4562 and an expected gain of 0.35 QALY, resulting in an ICER of USD -13056.56. The results were shown to be robust upon one-way sensitivity analysis. Upon Monte Carlo simulation, the PHI strategy was more cost-effective for 100% of the iterations. The PHI strategy demonstrated dominance over the PSA strategy regardless of what WTP threshold we use.

CONCLUSIONS

A PHI-based screening strategy may be more cost-effective than a PSA-based strategy for prostate cancer detection in Chinese men. These results support consideration of a PHI-based approach for prostate cancer in Hong Kong.

Serum and urinary biomarkers for detection and active surveillance of prostate cancer

PURPOSE OF REVIEW

To provide a comprehensive review of the available biomarkers for the detection and active surveillance of prostate cancer and simplify decision-making while choosing between them.

RECENT FINDINGS

The limitations of PSA and mpMRI and the invasive nature of prostate biopsy has led to a constant search for serum and urinary biomarkers for both the detection and monitoring during active surveillance of prostate cancer. 4K, PHI and PCA3 have been validated in prospective clinical trials for initial detection of prostate cancer and recent evidence points to potential differentiation between indolent and aggressive cancer. However, the usage in monitoring tumor dynamics is debatable because of lack of conclusive evidence. The answer to the existing problems lies in high-quality studies to establish definitive evidence and also to help choose between the plethora of biomarkers available today.

SUMMARY

Despite the advancements in innovation and usage of biomarkers in prostate cancer, there exists tremendous potential in improving them to fulfil the unmet need that exists today. Studies to establish conclusive evidence and integration with imaging can tremendously aid diagnosis and monitoring.

A comparison of prostate health index, total PSA, %free PSA, and proPSA in a contemporary US population-The MiCheck-01 prospective trial

BACKGROUND

Increasing numbers of patients are presenting with aggressive prostate cancer (CaP); therefore, there exists a need to optimally identify these patients pre-biopsy.

OBJECTIVES

To compare the accuracy of total prostate specific antigen (PSA), %free PSA, and prostate health index (PHI) to differentiate between patients without CaP, with non-aggressive (Gleason 3 + 3, non-AgCaP) and with aggressive (Gleason ≥ 3 + 4, AgCaP) in a contemporary US population.

DESIGN, SETTINGS, AND PARTICIPANTS

Serum samples were collected from 332 US patients scheduled for biopsy due to an elevated age-adjusted PSA. Site and Central biopsy pathologic assessment were performed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Testing of PSA, free PSA, proPSA, and PHI was performed along with central pathology review. Test performance using logistic regression analysis for differentiating CaP from non-CaP as well as non-AgCaP from AgCaP was evaluated.

RESULTS AND LIMITATIONS

Central pathology review resulted in 32 upgrades including 14 Gleason 3 + 3 scores being upgraded to AgCaP with final distribution of 148 no-CaP, 64 non-AgCaP, and 120 AgCaP patients. Receiver operator curve (ROC) analysis of the different tests showed that PHI performed best at differentiating CaP from no-CaP subjects (area under the receiver operator curve 0.79). In contrast, the different tests were essentially equivalent in differentiating AgCaP vs. non-AgCaP.

CONCLUSIONS

In this recent US study of prebiopsy patients we observed a high proportion of AgCaP patients consistent with previous studies in contemporary US populations. Central Gleason review is recommended for multi-institutional studies comparing biomarkers. PHI was superior to PSA, free PSA, %free PSA, and proPSA in detecting CaP in this population but was not superior at differentiating AgCaP from non-AgCaP.

[Clinical value of serum isoform [-2] proprostate-specific antigen and its derivatives in predicting aggressive prostate cancer]

OBJECTIVE

To explore the clinical value of serum isoform [-2] proprostate-specific antigen (p2PSA) and its derivatives %p2PSA and prostate health index (PHI) in predicting aggressive prostate cancer (PCa).

METHODS

The pre-operation serum and basic clinical data of 322 patients with PCa (including 143 patients diagnosed with PCa by transrectal ultrasound-guided prostate biopsy and 179 patients undergoing radical prostatectomy) in Peking University First Hospital were collected from August 2015 to May 2018. Serum total prostate-specific antigen (tPSA), free prostate antigen (fPSA) and fPSA/tPSA (f/t) and the p2PSA level of all these patients were measured on automatic immune analyzers DxI800, and then %p2PSA and PHI were calculated. The prostate pathologic result was considered as the gold standard to evaluate the Gleason score of the patients with PCa. Receiver operator curves (ROC) were used to assess the ability of p2PSA, %p2PSA and PHI to predict aggressive PCa (pathologic Gleason score≥7) compared with those traditional markers tPSA, fPSA and f/t.

RESULTS

Among these patients, the p2PSA, %p2PSA and PHI median levels were significantly higher in patients with pathologic Gleason score≥7 than those with Gleason score<7 (p2PSA: 30.22 ng/L vs. 18.33 ng/L; %p2PSA: 2.50 vs. 1.27; PHI: 91.81 vs. 35.44; all P<0.01). The area under curve (AUC) of %p2PSA and PHI (0.770, 0.760) in predicting Gleason score≥7 were higher than those of the traditional indicators tPSA, fPSA and f/t (AUC were 0.648, 0.536 and 0.693, respectively). Among those patients diagnosed with PCa by transrectal ultrasound-guided prostate biopsy, the AUC of %p2PSA and PHI (AUC were 0.808 and 0.801, respectively) in predicting Gleason score≥7 were higher than those of the traditional indicators tPSA, fPSA and f/t (AUC were 0.729, 0.655 and 0.665 respectively). Among those patients undergoing radical prostatectomy, PHI and %p2PSA also had the trend of higher predictive value than those of the traditional indicators. The AUC of %p2PSA and PHI were 0.798 and 0.744, respectively while the AUC of tPSA, fPSA and f/t were 0.625, 0.507 and 0.697, respectively.

CONCLUSION

Compared with traditional markers tPSA, fPSA and f/t, %p2PSA and PHI had much higher predictive value for aggressive PCa, which may help clinicians to evaluate the therapeutic regime and make more appropriate management plan for the patients.

Explication of the roles of prostate health index (PHI) and urokinase plasminogen activator (uPA) as diagnostic and predictor tools for prostate cancer in equivocal PSA range of 4-10 ng/mL

Background

Prostate cancer (PCa) is one of the most commonly encountered cancers and the leading cause of death worldwide. Currently used biomarkers accounts difficulties in discriminating benign from malignant cases or predicting outcome, so investigating new biomarkers performance is needed.

Objectives

Assessment of diagnostic and predictor roles of prostate health index (PHI) and urokinase plasminogen activator (uPA) in PCa.

Methods

194 males with initial tPSA of 4-10 ng/mL were categorized into three groups: PCa, benign prostatic hyperplasia (BPH) and healthy control. Serum levels of tPSA, fPSA, p2PSA, and uPA were performed by ELISA with calculation of PHI as (p2PSA/fPSA) × √PSA.

Results

PHI and uPA were significantly higher in PCa patients relevant to BPH and healthy control (p ≤ 0.001). Both markers outperformed all assessed biomarkers and showed the highest area under the curve (AUC) in ROC curve analysis. Both were significantly higher in PCa patients with {Gleason score ≥ 7, late stages (cT2b,c; T3), LN extension and distant metastasis}relative to their counterparts. Additionally, PHI and uPA and were independent predictors of distant metastasis and Gleason score ≥ 7, while PHI was predictor of LN invasion (β = 0.25, p = 0.004).

Conclusion

PHI and uPA would be of potential value in discriminating between PCa, BPH and healthy men in addition, both are promising as independent predictors of adverse pathological features.

Serum and urine biomarkers for detecting clinically significant prostate cancer

Since the "prostate-specific antigen (PSA) era," we have seen an increase in unnecessary biopsies, which has ultimately lead to an overtreatment of low-risk cancers. Given the limitations of prostate-specific antigen and the invasive nature of prostate biopsy several serum and urinary biomarkers have been developed. In this paper, we provide a comprehensive review of the available biomarkers for the detection clinically significant prostate cancer namely PHI, 4Kscore, PCA3, MiPS, SelectMDx, ExosomeDX. Current literature suggests that these biomarkers can improve detection of clinically significant prostate cancer reducing overtreatment and making treatment strategies more cost-effective. Nevertheless, large prospective studies with head-to-head-comparisons of the available biomarkers are necessary to fully assess the potential of incorporating biomarkers in routine clinical practice.

A predictive model for prostate cancer incorporating PSA molecular forms and age

The diagnostic specificity of prostate specific antigen (PSA) is limited. We aimed to characterize eight anti-PSA monoclonal antibodies (mAbs) to assess the prostate cancer (PCa) diagnostic utility of different PSA molecular forms, total (t) and free (f) PSA and PSA complexed to α₁-antichymotrypsin (complexed PSA). MAbs were obtained by immunization with PSA and characterized by competition studies, ELISAs and immunoblotting. With them, we developed sensitive and specific ELISAs for these PSA molecular forms and measured them in 301 PCa patients and 764 patients with benign prostate hyperplasia, and analyzed their effectiveness to discriminate both groups using ROC curves. The free-to-total (FPR) and the complexed-to-total PSA (CPR) ratios significantly increased the diagnostic yield of tPSA. Moreover, based on model selection, we constructed a multivariable logistic regression model to predictive PCa that includes tPSA, fPSA, and age as predictors, which reached an optimism-corrected area under the ROC curve (AUC) of 0.86. Our model outperforms the predictive ability of tPSA (AUC 0.71), used in clinical practice. In conclusion, The FPR and CPR showed better diagnostic yield than tPSA. In addition, the PCa predictive model including age, fPSA and complexed PSA, outperformed tPSA detection efficacy. Our model may avoid unnecessary biopsies, preventing harmful side effects and reducing health expenses.

Beyond PSA: The Role of Prostate Health Index (phi)

Background: Widespread use of prostate specific antigen (PSA) in screening procedures allowed early identification of an increasing number of prostate cancers (PCas), mainly including indolent cancer. Availability of different therapeutic strategies which have a very different impact on the patient’s quality of life suggested a strong need for tools able to identify clinically significant cancer at diagnosis. Multi-parametric magnetic resonance showed very good performance in pre-biopsy diagnosis. However, it is an expensive tool and requires an experienced radiologist. In this context, a simple blood-based test is worth investigating. In this context, researchers focused their attention on the development of a laboratory test able to minimize overdiagnosis without losing the identification of aggressive tumors. Results: Recent literature data on PCa biomarkers revealed a clear tendency towards the use of panels of biomarkers or a combination of biomarkers and clinical variables. Phi, the 4Kscore, and Stockholm3 as circulating biomarkers and the Mi-prostate score, Exo DX Prostate, and Select MD-X as urinary biomarker-based tests have been developed. In this scenario, phi is worthy of attention as a noninvasive test significantly associated with aggressive PCa. Conclusions: Literature data showed that phi had good diagnostic performance to identify clinically significant (cs) PCa, suggesting that it could be a useful tool for personalized treatment decision-making. In this review, phi potentialities, limitations, and comparisons with other blood- and urinary-based tests were explored.

A piece in prostate cancer puzzle: Future perspective of novel molecular signatures

Prostate cancer (PCa) has a variable biological potential. It constitutes the second most common cancer amongst men worldwide and the fifth most common cancer in Saudi Arabia. Identifying men at higher risk of developing PCa, differentiating indolent from aggressive disease and predicting the likelihood of progression will improve decision-making and selection for active surveillance protocols. Biomarkers have been utilized for PCa screening and predicting cancer behavior and response to treatment. The prostate specific antigen (PSA) screening helps detect PCa in early stages, while implementing a plan for management and outcome. However, PSA screening is still controversial, due to the risks of over diagnosis and treatment, and its inability to detect a good proportion of advanced tumors. Alternatively, a new era of PCa biomarkers has emerged with higher PCa specificity than PSA and its isoforms hopefully improving screening methods, such as Prostate Health Index (PHI) score, Progensa Prostate Cancer Antigen 3 (PCA3), Mi-Prostate Score (MiPS), Prostate Stem Cell Antigen (PSCA), 4Kscore test, and Urokinase Plasminogen Activation (uPA and uPAR). Few novel biomarkers have shown promise in preliminary results. This review will display promising biomarkers including some important FDA approved ones, highlighting their clinical implication and future place in the PCa puzzle, along with addressing their current limitations.

The ternary complex factor protein ELK1 is an independent prognosticator of disease recurrence in prostate cancer

BACKGROUND

Both hormone-sensitive and castration- and enzalutamide-resistant prostate cancers (PCa) depend on the ternary complex factor (TCF) protein ELK1 to serve as a tethering protein for the androgen receptor (AR) to activate a critical set of growth genes. The two sites in ELK1 required for AR binding are conserved in other members of the TCF subfamily, ELK3 and ELK4. Here we examine the potential utility of the three proteins as prognosticators of disease recurrence in PCa.

METHODS

Transcriptional activity assays; Retrospective analysis of PCa recurrence using data on 501 patients in The Cancer Genome Atlas (TCGA) database; Unpaired Wilcoxon rank-sum test and multiple comparison correction using the Holm's method; Spearman's correlations; Kaplan-Meier methods; Univariable and multivariable Cox regression analyses; LASSO-based penalized Cox regression models; Time-dependent area under the receiver operating characteristic (ROC) curve.

RESULTS

ELK4 but not ELK3 was coactivated by AR similar to ELK1. Tumor expression of neither ELK3 nor ELK4 was associated with disease-free survival (DFS). ELK1 was associated with higher clinical T-stage, pathology T-stage, Gleason score, prognostic grade, and positive lymph node status. ELK1 was a negative prognosticator of DFS, independent of ELK3, ELK4, clinical T-stage, pathology T-stage, prognostic grade, lymph node status, age, and race. Inclusion of ELK1 increased the abilities of the Oncotype DX and Prolaris gene panels to predict disease recurrence, correctly predicting disease recurrence in a unique subset of patients.

CONCLUSIONS

ELK1 is a strong, independent prognosticator of disease recurrence in PCa, underscoring its unique role in PCa growth. Inclusion of ELK1 may enhance the utility of currently used prognosticators for clinical decision making in prostate cancer.

Merging new-age biomarkers and nanodiagnostics for precision prostate cancer management

The accurate identification and stratified treatment of clinically significant early-stage prostate cancer have been ongoing concerns since the outcomes of large international prostate cancer screening trials were reported. The controversy surrounding clinical and cost benefits of prostate cancer screening has highlighted the lack of strategies for discriminating high-risk disease (that requires early treatment) from low-risk disease (that could be managed using watchful waiting or active surveillance). Advances in molecular subtyping and multiomics nanotechnology-based prostate cancer risk delineation can enable refinement of prostate cancer molecular taxonomy into clinically meaningful and treatable subtypes. Furthermore, the presence of intertumoural and intratumoural heterogeneity in prostate cancer warrants the development of novel nanodiagnostic technologies to identify clinically significant prostate cancer in a rapid, cost-effective and accurate manner. Circulating and urinary next-generation prostate cancer biomarkers for disease molecular subtyping and the newest complementary nanodiagnostic platforms for enhanced biomarker detection are promising tools for precision prostate cancer management. However, challenges in merging both aspects and clinical translation still need to be overcome.

Platelet-to-lymphocyte ratio and systemic immune-inflammation index versus circulating prostate cells to predict significant prostate cancer at first biopsy

OBJECTIVE

It has been reported that the systemic immune-inflammation index (SII) and platelet-to-lymphocyte ratio (PLR) are higher in men with prostate cancer. We compare their use with the percentage of free prostate-specific antigen (PSA), PSA density, and primary circulating prostate cells (CPCs) to predict clinically significant prostate cancer at first biopsy in men with a PSA of 4-10 ng/mL.

MATERIAL AND METHODS

Consecutive men with suspicion of prostate cancer underwent a 12-core transrectal ultrasound-guided prostate biopsy; total serum PSA, the percentage of free PSA, prostate ultrasound to calculate PSA density, and absolute neutrophil, lymphocyte, and platelet counts were used for risk assessment. CPCs were detected using differential gel centrifugation and immunocytochemistry with anti-PSA and anti-P504S. A malignant CPC was defined as a cell-expressing PSA and P504S and defined as positive or negative. Biopsies were classified as indicating cancer or no cancer. Areas under the curve for each parameter were calculated and compared, and diagnostic yields were calculated.

RESULTS

A total of 1223 men participated, and 467 (38%) had a biopsy positive for cancer, whereas 353/467 (76%) had clinically significant prostate cancer. The PLR was significantly higher in men with prostate cancer; there was no significant difference for the SII. The areas under the curves were CPC 0.84, the percentage of free PSA was 0.79, PLR 0.65, PSA density 0.62, and SII 0.46. Neither the PLR nor the SII discriminated between patients with clinically significant prostate cancer, indolent cancer, and benign prostatic disease.

CONCLUSION

Based on the results of this study, neither the SII nor PLR could differentiate between clinically significant prostate cancer and indolent cancer/benign disease at initial biopsy.

Multi-omic serum biomarkers for prognosis of disease progression in prostate cancer

Background

Predicting the clinical course of prostate cancer is challenging due to the wide biological spectrum of the disease. The objective of our study was to identify prostate cancer prognostic markers in patients ‘sera using a multi-omics discovery platform.

Methods

Pre-surgical serum samples collected from a longitudinal, racially diverse, prostate cancer patient cohort (N = 382) were examined. Linear Regression and Bayesian computational approaches integrated with multi-omics, were used to select markers to predict biochemical recurrence (BCR). BCR-free survival was modeled using unadjusted Kaplan–Meier estimation curves and multivariable Cox proportional hazards analysis, adjusted for key pathologic variables. Receiver operating characteristic (ROC) curve statistics were used to examine the predictive value of markers in discriminating BCR events from non-events. The findings were further validated by creating a training set (N = 267) and testing set (N = 115) from the cohort.

Results

Among 382 patients, 72 (19%) experienced a BCR event in a median follow-up time of 6.9 years. Two proteins—Tenascin C (TNC) and Apolipoprotein A1V (Apo-AIV), one metabolite—1-Methyladenosine (1-MA) and one phospholipid molecular species phosphatidic acid (PA) 18:0-22:0 showed a cumulative predictive performance of AUC = 0.78 [OR (95% CI) = 6.56 (2.98–14.40), P < 0.05], in differentiating patients with and without BCR event. In the validation set all four metabolites consistently reproduced an equivalent performance with high negative predictive value (NPV; > 80%) for BCR. The combination of pTstage and Gleason score with the analytes, further increased the sensitivity [AUC = 0.89, 95% (CI) = 4.45–32.05, P < 0.05], with an increased NPV (0.96) and OR (12.4) for BCR. The panel of markers combined with the pathological parameters demonstrated a more accurate prediction of BCR than the pathological parameters alone in prostate cancer.

Conclusions

In this study, a panel of serum analytes were identified that complemented pathologic patient features in predicting prostate cancer progression. This panel offers a new opportunity to complement current prognostic markers and to monitor the potential impact of primary treatment versus surveillance on patient oncological outcome.

Multiparametric MRI for prostate cancer diagnosis: current status and future directions

The current diagnostic pathway for prostate cancer has resulted in overdiagnosis and consequent overtreatment as well as underdiagnosis and missed diagnoses in many men. Multiparametric MRI (mpMRI) of the prostate has been identified as a test that could mitigate these diagnostic errors. The performance of mpMRI can vary depending on the population being studied, the execution of the MRI itself, the experience of the radiologist, whether additional biomarkers are considered and whether mpMRI-targeted biopsy is carried out alone or in addition to systematic biopsy. A number of challenges to implementation remain, such as ensuring high-quality execution and reporting of mpMRI and ensuring that this diagnostic pathway is cost-effective. Nevertheless, emerging clinical trial data support the adoption of this technology as part of the standard of care for the diagnosis of prostate cancer.

Optimal threshold of the prostate health index in predicting aggressive prostate cancer using predefined cost-benefit ratios and prevalence

PURPOSES

The aim of the study was to determine optimal threshold of the Prostate Health Index (Phi) for predicting aggressive prostate cancer (PCa), taking into account misclassification costs, prevalence, and plausible risk factors.

METHODS

This prospective cohort study analyzed patients undergoing prostate biopsy and Phi testing. The primary endpoint was aggressive PCa, defined as biopsy Gleason score ≥ 7. The data about age, total prostate-specific antigen (PSA), percentage of free PSA (%fPSA), and digital rectal examination (DRE) were extracted from the patient files. We divided the patients to the low- and high-risk group. The clinical usefulness of the Phi was assessed by the decision curve analysis. The predictive performance was assessed using the area under the receiver operating characteristic curve (AUC), per-class metrics, and the potential reduction in unnecessary biopsies. The uncertain interval of Phi values was also determined.

RESULTS

There were 200 men included in the study, 35 (17.5%) of them having aggressive PCa. Important predictors of aggressive PCa were %fPSA, DRE, Phi, and belonging to the high-risk group. With optimal threshold of 30.7, about 32% unnecessary biopsies would be avoided. The optimal threshold of Phi was lower in the high-risk group than in the low-risk group. The AUC for detection of aggressive PCa was 0.791. Per-class metrics showed that the Phi has insufficient diagnostic accuracy. The lower and upper limits of the uncertain interval were 41.8 and 51.4, respectively.

CONCLUSION

Different thresholds of the Phi could be optimal, depending on prevalence, patient characteristics, and misclassification costs. Further studies with a larger patient sample are necessary to confirm our conclusions.

Prostate health index density predicts aggressive pathological outcomes after radical prostatectomy in Taiwanese patients

BACKGROUND

There are models to predict pathological outcomes based on established clinical and prostate-specific antigen (PSA)-derived parameters; however, they are not satisfactory. p2PSA and its derived biomarkers have shown promise for the diagnosis and prognosis of prostate cancer (PCa). The aim of this study was to investigate whether p2PSA-derived biomarkers can assist in the prediction of aggressive pathological outcomes after radical prostatectomy (RP).

METHODS

We prospectively enrolled patients who were diagnosed with PCa and treated with RP between February 2017 and December 2018. Preoperative blood samples were analyzed for tPSA, free PSA (fPSA), percentage of fPSA (%fPSA), [-2]proPSA (p2PSA), and percentage of p2PSA (%p2PSA). Prostate health index (PHI) was calculated as (p2PSA/fPSA) × √tPSA. Prostate volume was determined by transrectal ultrasound using the ellipsoid formula, and PHI density was calculated as PHI/prostate volume. The areas under the receiver operating characteristic curve were estimated for various PSA/p2PSA derivatives. Aggressive pathological outcomes measured after RP were defined as pathological T3 or a Gleason score (GS) >6 as determined in RP specimens.

RESULTS

One hundred and forty-four patients were included for analysis. Postoperative GS was >6 in 86.1% of the patients, and pT stage was T3a or more in 54.2%. Among all PSA- and p2PSA-derived biomarkers, PHI density was the best biomarker to predict aggressive pathological outcomes after RP. The odds ratio of having an aggressive pathological outcome of RP was 8.796 (p = 0.001). In multivariate analysis, adding %fPSA to base model did not improve the accuracy (area under curve), but adding PHI and PHI density to base model improved the accuracy by 2% and 16%, respectively, in predicting pT3 stage or GS ≥ 7. The risk of pT3 stage or GS ≥ 7 was 20.8% for PHI density <1.125, and 64.6% for PHI density >1.125 (sensitivity: 74.6% and specificity: 88.9%).

CONCLUSION

PHI density may further aid in predicting aggressive pathological outcomes after RP. This biomarker may be useful in preoperative counseling and may have potential in decision making when choosing between definitive treatment and active surveillance of newly diagnosed PCa.

The importance of plasma arginine level and its downstream metabolites in diagnosing prostate cancer

PURPOSE

There is still no certain threshold value of prostate-specific antigen (PSA) for prostate cancer diagnosis. We aimed to investigate the predictive value of arginine and its metabolites for diagnosing prostate cancer in patients with PSA 4-10 ng/ml and evaluate their usefulness as prognostic tumor markers.

METHODS

Seventy-eight patients with a mean age of 64.50 ± 5.49 years were included in our prospective observational study between November 2016 and March 2017. They were divided into two equal groups according to the pathologic results of prostate biopsy (benign vs. malignant). Plasma arginine and ornithine levels were analyzed before biopsy by liquid chromatography-tandem mass spectrometry. ELISA was used for analyzing urinary diacetylspermine.

RESULTS

In PSA-adjusted analysis, the malignant group had lower plasma arginine levels (p = 0.021) and arginine to ornithine ratio (AOR) (p = 0.010), but higher plasma ornithine levels (p = 0.012) and urinary diacetylspermine levels (p < 0.001) as compared with the benign group. While arginine (r = - 0.628, p < 0.001) and AOR (r = - 0.714, p < 0.001) were negatively correlated with D'Amico clinical classification (p < 0.001), ornithine (r = 0.659, p < 0.001) and diacetylspermine (r = 0.710, p < 0.001) were found to be positively correlated (p < 0.001). In multivariate analysis, ornithine [OR 3.264, 95% CI (1.045-10.196), p = 0.042] and diacetylspermine [OR 6.982, 95% CI (2.403-20.290), p < 0.001] were found to be more significant in detection of prostate cancer.

CONCLUSION

Plasma arginine, ornithine, AOR and urinary diacetylspermine levels may be used as molecular markers to predict prostate biopsy outcomes in patients with PSA 4-10 ng/ml. But according to our results, the use of ornithine and diacethylspermine prior to biopsy seems to be the most cost-effective diagnostic strategy.

Dandelion Root and Lemongrass Extracts Induce Apoptosis, Enhance Chemotherapeutic Efficacy, and Reduce Tumour Xenograft Growth In Vivo in Prostate Cancer

Many conventional chemotherapies have indicated side effects due to a lack of treatment specificity and are thus not suitable for long-term usage. Natural health products are well-tolerated and safe for consumption, and some have pharmaceutical uses particularly for their anticancer effects. We have previously reported the anticancer efficacy of dandelion (Taraxacum officinale) root and lemongrass (Cymbopogon citratus) extracts. However, their efficacy on prostate cancer and their interactions with standard chemotherapeutics have not been studied to determine if they will be suitable for adjuvant therapies. If successful, these extracts could potentially be used in conjunction with chemotherapeutics to minimize the risk of drug-related toxicity and enhance the efficacy of the treatment. We have demonstrated that both dandelion root extract (DRE) and lemongrass extract (LGE) exhibit selective anticancer activity. Importantly, DRE and LGE addition to the chemotherapeutics taxol and mitoxantrone was determined to enhance the induction of apoptosis when compared to individual chemotherapy treatment alone. Further, DRE and LGE were able to significantly reduce the tumour burden in prostate cancer xenograft models when administered orally, while also being well-tolerated. Thus, the implementation of these well-tolerated extracts in adjuvant therapies could be a selective and efficacious approach to prostate cancer treatment.

Assessment on clinical value of prostate health index in the diagnosis of prostate cancer

In this study, we performed a comprehensive estimation and assessment for the clinical value of prostate health index (PHI) in diagnosing prostate cancer. Using the bivariate mixed-effect model, we calculated the following parameters and their 95% confidence internals (CIs), including sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio and symmetric receiver operator characteristic. Twenty eligible studies with a total number of 5543 subjects were included in the final analysis. The estimated sensitivity was 0.75 (95% CI: 0.70-0.79) and the specificity was 0.69 (95% CI: 0.58-0.83). The pooled area under the curve was 0.78 (95% CI: 0.74-0.81). The combined positive likelihood ratio was 2.45 (95% CI: 2.19-2.73) and the negative likelihood ratio was 0.36 (95% CI: 0.31-0.43). The diagnostic odds ratio was 6.73 (95% CI: 5.38-8.44). The posttest probability was 40% under the present positive likelihood ratio of 2.45. It seems there was no significant difference between Asian population and Caucasian population population in sensitivity and specificity. But the overlap of AUC 95% CI indicated that the diagnostic accuracy of PHI was slightly higher in the Asian population population setting than that in the Caucasian population population population (0.83 vs 0.76). Similarly, there was also overlap in AUC 95% CI, which suggested that sample size may be one of heterogeneity source. The PHI has a moderate diagnostic accuracy for detecting prostate cancer. The discrimination ability of PHI is slightly prior to free/total prostate-specific antigen. It seems that ethnicity has an influence on the clinical value of PHI in the diagnostic of prostate cancer.

Cancer overdiagnosis: a biological challenge and clinical dilemma

For cancer screening to be successful, it should primarily detect cancers with lethal potential or their precursors early, leading to therapy that reduces mortality and morbidity. Screening programmes have been successful for colon and cervical cancers, where subsequent surgical removal of precursor lesions has resulted in a reduction in cancer incidence and mortality. However, many types of cancer exhibit a range of heterogeneous behaviours and variable likelihoods of progression and death. Consequently, screening for some cancers may have minimal impact on mortality and may do more harm than good. Since the implementation of screening tests for certain cancers (for example, breast and prostate cancers), a spike in incidence of in situ and early-stage cancers has been observed, but a link to reduction in cancer-specific mortality has not been as clear. It is difficult to determine how many of these mortality reductions are due to screening and how many are due to improved treatments of tumours. In cancers with lower incidence but high mortality (for example, pancreatic cancer), screening has focused on high-risk populations, but challenges similar to those for general population screening remain, particularly with regard to finding lesions with difficult-to-characterize malignant potential (for example, intraductal papillary mucinous neoplasms). More sensitive screening methods are detecting smaller and smaller lesions, but this has not been accompanied by a comparable reduction in the incidence of invasive cancers. In this Opinion article, we focus on the contribution of screening in general and high-risk populations to overdiagnosis, the effects of overdiagnosis on patients and emerging strategies to reduce overdiagnosis of indolent cancers through an understanding of tumour heterogeneity, the biology of how cancers evolve and progress, the molecular and cellular features of early neoplasia and the dynamics of the interactions of early lesions with their surrounding tissue microenvironment.

The burden of prostate cancer is associated with human development index: evidence from 87 countries, 1990-2016

Aim

To examine the temporal patterns of the prostate cancer burden and its association with human development.

Subject and methods

The estimates of the incidence and mortality of prostate cancer for 87 countries were obtained from the Global Burden of Disease 2016 study for the period 1990 to 2016. The human development level of a country was measured using its human development index (HDI): a summary indicator of health, education, and income. The association between the burden of prostate cancer and the human development index (HDI) was measured using pairwise correlation and bivariate regression. Mortality-to-incidence ratio (MIR) was employed as a proxy for the survival rate of prostate cancer.

Results

Globally, 1.4 million new cases of prostate cancer arose in 2016 claiming 380,916 lives which more than doubled from 579,457 incident cases and 191,687 deaths in 1990. In 2016, the age-standardised incidence rate (ASIR) was the highest in very high-HDI countries led by Australia with ASIR of 174.1/100,000 and showed a strong positive association with HDI (r = 0.66); the age-standardised mortality rate (ASMR), however, was higher in low-HDI countries led by Zimbabwe with ASMR of 78.2/100,000 in 2016. Global MIR decreased from 0.33 in 1990 to 0.26 in 2016. Mortality-to-incidence ratio (MIR) exhibited a negative gradient (r = - 0.91) with human development index with tenfold variation globally with seven countries recording MIR in excess of 1 with the USA recording the minimum MIR of 0.10.

Conclusion

The high mortality and lower survival rates in less-developed countries demand all-inclusive solutions ranging from cost-effective early screening and detection to cost-effective cancer treatment. In tackling the rising burden of prostate cancer predictive, preventive and personalised medicine (PPPM) can play a useful role through prevention strategies, predicting PCa more precisely and accurately using a multiomic approach and risk-stratifying patients to provide personalised medicine.

A critical appraisal of biomarkers in prostate cancer

PURPOSE

A number of urine and blood-based biomarker tests have been described for prostate cancer, although to date there has only been a limited exploration of the methodology behind the validation studies that underpin these tests.

METHODS

In this review, a selection of commercially available urine and blood-based biomarker tests for prostate cancer are described, and the underlying key validation studies for each test are critically appraised using the Standards for Reporting Diagnostic Accuracy (STARD) 2015 statement.

RESULTS

The ExoDx Prostate Intelliscore, SelectMDx, Progensa PCA3, Mi-Prostate Score, 4K Score, and Prostate Health Index (PHI) tests were reviewed. Most of the validation studies supporting these tests perform exploratory analyses to determine cut-off values in a post hoc manner, comprise cohorts that are primarily Caucasian, report receiver operating characteristic curves that combine the biomarker's result with established clinical nomograms and are based on a reference standard (prostate biopsy) that lacks central pathology review. Deficiencies in STARD reporting guidelines include frequent failure to provide a published study protocol, prospective study registration in a registry, a flow diagram, justification for sample size determination, a discussion of adverse events with testing, and information on how missing or indeterminate test results should be managed.

CONCLUSIONS

Key validation studies that support many commercially available urine and blood-based biomarkers for prostate cancers have deficiencies in transparency based on STARD reporting guidelines, and limitations in methodology must be considered when deciding when these tests should be applied in clinical practice.

A Rich Array of Prostate Cancer Molecular Biomarkers: Opportunities and Challenges

Prostate cancer is the most prevalent non-skin cancer in men and is the leading cause of cancer-related death. Early detection of prostate cancer is largely determined by a widely used prostate specific antigen (PSA) blood test and biopsy is performed for definitive diagnosis. Prostate cancer is asymptomatic in the early stage of the disease, comprises of diverse clinico-pathologic and progression features, and is characterized by a large subset of the indolent cancer type. Therefore, it is critical to develop an individualized approach for early detection, disease stratification (indolent vs. aggressive), and prediction of treatment response for prostate cancer. There has been remarkable progress in prostate cancer biomarker discovery, largely through advancements in genomic technologies. A rich array of prostate cancer diagnostic and prognostic tests has emerged for serum (4K, phi), urine (Progensa, T2-ERG, ExoDx, SelectMDx), and tumor tissue (ConfirmMDx, Prolaris, Oncoytype DX, Decipher). The development of these assays has created new opportunities for improving prostate cancer diagnosis, prognosis, and treatment decisions. While opening exciting opportunities, these developments also pose unique challenges in terms of selecting and incorporating these assays into the continuum of prostate cancer patient care.

Diagnosis of prostate cancer

Diagnosis of prostate cancer (PCa) and adequate staging play a fundamental role for clinical and patient care. Despite major advances in biology and imaging, rectal examination and prostate-specific antigen (PSA) blood test remain the cornerstone for screening, and multiparametricmagnetic resonance imaging (mpMRI) for local staging. Recent advances in mpMRI lead to standardised interpretation and increased prescription by clinicians in order to improve detection of clinically significant PCa and select patients requiring targeted biopsies. However its indication remains controversial in biopsy-naïve patients. Nuclear medicine is also in a continuous evolution and utilisation of new radiopharmaceutical agent like choline or 68gallium with computed tomography or magnetic resonance imaging has led to the improvement in the detection of lymph nodes, distant metastases and prostate recurrence. Considering this very heterogneneous disease, combined utilisation of these tools will help clinicians and patients in choosing the most appropriate and personalised treatment.

The Utility of Prostate Specific Antigen Density, Prostate Health Index, and Prostate Health Index Density in Predicting Positive Prostate Biopsy Outcome is Dependent on the Prostate Biopsy Methods

OBJECTIVE

To evaluate prognostic markers, prostate-specific antigen, prostate health index (PHI), and prostate volume indexed measures (prostate-specific antigen density and prostate health index density) for predicting positive prostate cancer biopsies in magnetic resonance (MR) transrectal ultrasound fused versus nonfused transrectal ultrasonography biopsy.

METHODS

A retrospective cohort of 211 patients that had at least 1 suspected MR lesion, Prostate Imaging-Reporting and Data System ≥3, and subsequent biopsy (2015-2017). Clinical characteristics and prognostic biomarkers were evaluated as predictors of prostate cancer detection by type of biopsy guidance (fused vs nonfused).

RESULTS

One-hundred twenty-one patients had nonfused and 90 had fused biopsies. PHI and PHID had greater area under the receiver operating characteristics curve (AUC) in predicting positive biopsies than prostate-specific antigen or PSAD for both nonfused and fused biopsy. PHI 0.78 (95% CI 0.67-0.88) and PHID 0.82 (95% CI 0.73-0.91) had the greatest AUC for predicting biopsy results for nonfused and fused biopsies, respectively. Multiple-variable models did not improve model fit compared to single variables. Based on Youden's index, a cut-off value of 45.9 for PHI in nonfused and 0.64 for PHID in fused biopsies would reduce the number of negative biopsies by 77.3% and 63.4%, respectively, but the percentage of missed clinically significant cancer biopsies would be 19% and 12%, respectively.

CONCLUSION

Our findings demonstrate that the choice of prognostic biomarkers for predicting positive biopsies is a function of the biopsy guidance method. Volume indexed derivatives appear to have greater value when a MRI-US fused method is used.

Smarter screening for prostate cancer

PURPOSE

Prostate cancer is the second commonest cancer among men. In the large European Randomized Study of Screening for Prostate Cancer (ERSPC) trial, prostate-specific antigen (PSA) screening has been shown to substantially reduce prostate cancer mortality. However, PSA screening is known to lead to more unnecessary prostate biopsies and over-diagnosis of clinically insignificant cancer. Therefore, it is imperative that smarter screening methods be developed to overcome the weaknesses of PSA screening. This review explores the novel screening tools that are available.

METHODS

A comprehensive literature search was performed using PubMed regarding newer biomarkers, imaging techniques and risk-predicting models that are used to screen for prostate cancer in mainly biopsy-naïve men.

RESULTS

Novel serum-based models like 4Kscore^® and prostate health index (PHI) are generally better than PSA alone in detecting clinically significant cancer. Similarly, urine-based biomarkers like prostate cancer antigen 3 (PCA3) and HOXC6/DLX1 have been shown to be more accurate than PSA screening. More recently, multiparametric magnetic resonance imaging (mpMRI) is gaining popularity for its ability to detect clinically significant cancer. There is also evidence that combining individual tests to develop prediction models can reliably predict high-risk prostate cancers while reducing the number of unnecessary biopsies. Combinations such as the Stockholm-3 model (STHLM3) and other novel combinations are presented in this review.

CONCLUSION

While we continue to find the smarter screening methods that are reliable, precise, and cost-effective, we continue to advocate shared decision-making in prostate cancer screening in order to work in our patients' best interests.

[Active surveillance of prostate cancer : An update]

Prostate cancer is a heterogeneous disease. In cases of low-risk prostate cancer, active surveillance represents an attractive alternative treatment. Significant complications of a definitive treatment can therefore be delayed or completely avoided. Despite strict inclusion criteria for active surveillance, the diagnosis of low-risk prostate cancer can be inaccurate and there is therefore a risk of missing the optimal point in time for definitive treatment. Multimodal diagnostics and continuous aftercare are therefore crucial.

Combining urinary DNA methylation and cell-free microRNA biomarkers for improved monitoring of prostate cancer patients on active surveillance

PURPOSE

Prostate cancer (CaP) patients with low-grade tumors are enrolled in active surveillance (AS) programs and monitored with digital rectal exams (DREs), prostate-specific antigen (PSA) tests, and periodic invasive biopsies. Patients are "reclassified" with higher-risk disease if they show signs of disease progression. However, AS patients who will reclassify cannot be easily identified upfront and suffer morbidities associated with biopsy. Biomarkers derived from noninvasively obtained specimens such as serum or urine samples are promising alternatives to monitor patients with clinically insignificant cancer. Previously, we have characterized and validated a urinary DNA methylation panel and a serum miRNA panel for the prediction of patient reclassification in 2 independent AS cohorts. In this exploratory study, we have investigated cell-free miRNAs in the urinary supernatant combined with urinary DNA methylation markers to form an integrative panel for prediction of AS patient reclassification.

METHODS

Post-DRE urine was collected from 103 CaP patients on active surveillance. Urinary sediment DNA methylation levels of selected genes were previously analyzed using qPCR-based MethyLight assay. Using qRT-PCR, we analyzed the urinary supernatants for relative quantities of 10 miRNAs previously shown to be associated with AS reclassification. Logistic regression and Receiver Operating Characteristics curve analyses were performed to assess the predictive ability of miRNAs and DNA methylation biomarkers.

RESULTS

We identified a 3-marker panel, consisting of miR-24, miR-30c and CRIP3 methylation, that was significant for prediction of patient reclassification (Odds ratio = 2.166, 95% confidence interval = 1.22-3.847) with a negative predictive value of 90.9%. Our 3-marker panel also demonstrated additive value to PSA for prediction of patient reclassification (c-statistic = 0.717, ROC bootstrapped 1000 iteration P = 0.041).

CONCLUSION

A urinary integrated panel of methylation and miRNA markers is a promising approach to identify AS patients at risk for reclassification. Our 3-marker panel, with its high negative predictive value, would be beneficial to identify and preclude AS patients with truly indolent cancer and to personalize monitoring strategies for AS patients.

Proteomics biomarkers for solid tumors: Current status and future prospects

Cancer is a heterogeneous multifactorial disease, which continues to be one of the main causes of death worldwide. Despite the extensive efforts for establishing accurate diagnostic assays and efficient therapeutic schemes, disease prevalence is on the rise, in part, however, also due to improved early detection. For years, studies were focused on genomics and transcriptomics, aiming at the discovery of new tests with diagnostic or prognostic potential. However, cancer phenotypic characteristics seem most likely to be a direct reflection of changes in protein metabolism and function, which are also the targets of most drugs. Investigations at the protein level are therefore advantageous particularly in the case of in-depth characterization of tumor progression and invasiveness. Innovative high-throughput proteomic technologies are available to accurately evaluate cancer formation and progression and to investigate the functional role of key proteins in cancer. Employing these new highly sensitive proteomic technologies, cancer biomarkers may be detectable that contribute to diagnosis and guide curative treatment when still possible. In this review, the recent advances in proteomic biomarker research in cancer are outlined, with special emphasis placed on the identification of diagnostic and prognostic biomarkers for solid tumors. In view of the increasing number of screening programs and clinical trials investigating new treatment options, we discuss the molecular connections of the biomarkers as well as their potential as clinically useful tools for diagnosis, risk stratification and therapy monitoring of solid tumors.

Green tea extract for prevention of prostate cancer progression in patients on active surveillance

Background

Active surveillance (AS) has evolved as a management strategy for men with low grade prostate cancer (PCa). However, these patients report anxiety, doubts about the possible progression of the disease as well as higher decisional conflict regarding selection of active surveillance, and have been reported to ultimately opt for treatment without any major change in tumor characteristics. Currently, there is a paucity of research that systematically examines alternate strategies for this target population.

Methods

We conducted a review the evidence from epidemiological, in vitro, preclinical and early phase trials that have evaluated green tea catechins (GTC) for secondary chemoprevention of prostate cancer, focused on men opting for active surveillanceof low grade PCa.

Results

Results of our review of the in vitro, preclinical and phase I-II trials, demonstrates that green tea catechins (GTC) can modulate several relevant intermediate biological intermediate endpoint biomarkers implicated in prostate carcinogenesis as well as clinical progression of PCa, without major side effects.

Discussion

Although clinical trials using GTC have been evaluated in early phase trials in men diagnosed with High-Grade Prostatic Intraepithelial Neoplasia, Atypical Small Acinar Proliferation and in men with localized disease before prostatectomy, the effect of GTC on biological and clinical biomarkers implicated in prostate cancer progression have not been evaluated in this patient population.

Conclusion

Results of these studies promise to provide a strategy for secondary chemoprevention, reduce morbidities due to overtreatment and improve quality of life in men diagnosed with low-grade PCa.

The impact of pre-existing cancer on survival of prostate cancer patients: A population-based study

Prostate cancer (PCa) is the second most common malignant tumors for male patients worldwide. However, whether a history of pre-existing cancer cases may affect the survival of prostate cancer patients is still not fully understood.We identified patients diagnosed with PCa between 2000 and 2014 from the Surveillance, Epidemiology, and End Results (SEER) linked database. We further made propensity score matching and then compared all-cause and cancer-specific survival between patients with and those without a pre-existing cancer. Cox proportional hazards models and Kaplan-Meier analysis were used for survival comparison.A total of 153,255 patients with PCa were included for analysis, of whom 5939 had a history of pre-existing cancer, including hematologic and lymph (11%), intestine (19%), urinary system (36%), head and neck (9%), lung (5%), skin (12%), and others (8%). Patients with a pre-existing cancer had a worse prognosis compared with those without a pre-existing cancer [all-cause death: hazard ratio (HR) = 2.74, P < .001; cancer-special death: HR = 3.98, P < .001]. Importantly, cancers in urinary bladder prior to PCa had a most adverse impact on all-cause (HR = 5.00, P < .001) and cancer-specific death risk (HR = 10.45, P < .001). Time between the pre-existing cancer and PCa had a dose-dependent effect on survival of PCa patients, with a decreased death risk as the increase of the interval time.Pre-existing cancer has a negative impact on the prognosis of patients with PCa, which is most evident in the presence of a pre-existing urinary bladder cancer. Our results provide epidemiologic evidence with low between-group bias, large sample size, and long-term follow-up, highlighting the need for site-, and interval-time-based clinical management for patients with PCa who had a pre-existing cancer.

[Prostate cancer screening: Reasons of controversy]

We propose herein a short synthesis of evidence leading to deny organized screening of prostate cancer using PSA plus or minus rectal digital examination. Nevertheless, many scientific societies support opportunistic screening on basis of shared decision. Today, numerous proposals had been made to reduce the overdiagnosis and overtreatreatment.

A Multicentre Evaluation of the Role of the Prostate Health Index (PHI) in Regions with Differing Prevalence of Prostate Cancer: Adjustment of PHI Reference Ranges is Needed for European and Asian Settings

Asians have a lower incidence of prostate cancer (PC). We compared the performance of the Prostate Health Index (PHI) for 2488 men in different ethnic groups (1688 Asian and 800 European men from 9 sites) with PSA 2-20ng/ml and PHI test and transrectal ultrasound-guided biopsy results available. Of these, 1652 men had PSA 2-10ng/ml and a normal digital rectal examination and underwent initial biopsy. The proportions of PC (Gleason ≥6) and higher-grade PC (HGPC, Gleason ≥7) across different PHI ranges were compared. The performance of PSA and PHI was compared using the area under the receiver operating characteristic curve (AUC) and decision curve analyses (DCA). Among Asian men, HGPC would be diagnosed in 1.0%, 1.9%, 13%, and 30% of men using PHI thresholds of <25, 25-35, 35-55, and >55, respectively. At 90% sensitivity for HGPC (PHI >30), 56% of biopsies and 33% of Gleason 6 PC diagnoses could have been avoided. Among European men, HGPC would be diagnosed in 4.1%, 4.3%, 30%, and 34% of men using PHI thresholds of <25, 25-35, 35-55, and >55, respectively. At 90% sensitivity for HGPC (PHI >40), 40% of biopsies and 31% of Gleason 6 PC diagnoses could have been avoided. AUC and DCA confirmed the benefit of PHI over PSA. The benefit of PHI was also seen at repeat biopsy (n=397) and for PSA 10-20ng/ml (n=439). PHI is effective in cancer risk stratification for both European and Asian men. However, population-specific PHI reference ranges should be used. PATIENT SUMMARY: The Prostate Health Index (PHI) blood test helps to identify individuals at higher risk of prostate cancer among Asian and European men, and could significantly reduce unnecessary biopsies and overdiagnosis of prostate cancer. Different PHI reference ranges should be used for different ethnic groups.

Prostate cancer: updates on current strategies for screening, diagnosis and clinical implications of treatment modalities

Prostate cancer is the most common cancer in men by way of diagnosis and a leading cause of cancer-related deaths. Early detection and intervention remains key to its optimum clinical management. This review provides the most updated information on the recent methods of prostate cancer screening, imaging and treatment modalities. Wherever possible, clinical trial data has been supplemented to provide a comprehensive overview of current prostate cancer research and development. Considering the recent success of immunotherapy in prostate cancer, we discuss cell, DNA and viruses based, as well as combinatorial immunotherapeutic strategies in detail. Furthermore, the potential of nanotechnology is increasingly being realized, especially in prostate cancer research, and we provide an overview of nanotechnology-based strategies, with special emphasis on nanotheranostics and multifunctional nanoconstructs. Understanding these recent developments is critical to the design of future therapeutic strategies to counter prostate cancer.

Are localized prostate cancer biomarkers useful in the clinical practice?

Prostate cancer presents itself in a heterogeneous way with both aggressive and indolent forms. Despite the controversy surrounding its use, prostate-specific antigen screening ultimately leads to a greater number of diagnosed patients. One of the biggest challenges in clinical practice is to select the right patients for biopsy and, among diagnosed patients, to differentiate tumors with an indolent course from those with an unfavorable prognosis, in order to determine the best therapeutic decision for each case, avoiding unnecessary interventions. Currently, several types of biomarkers are available for clinical use in patients with prostate cancer, which include blood-based (prostate-specific antigen, Prostate Health Index®, 4K score®); urine sample-based (PCA3, SelectMDx®, ExoDx Prostate IntelliScore®); and biopsy, transurethral resection, or radical prostatectomy tissue-based (ConfirmMDx®, Oncotype®, Prolaris®, Decipher®). The aim of this review is to provide an overview of the current state of evidence and to highlight recent advances in the evaluation and diagnosis of prostate cancer, with emphasis on biomarkers related to diagnosis and to prognostic evaluation of localized prostate cancer.

Does extent of prostate-specific antigen fluctuation can predict Gleason score upgrading in low-risk prostate cancer patients?

OBJECTIVE

To evaluate the effect of prostate-specific antigen (PSA) fluctuation on Gleason score (GS) upgrading, disease upstaging, oncological outcomes in low-risk prostate cancer (PCa) patients who underwent robot-assisted laparoscopic radical prostatectomy (RARP) and met the inclusion criteria for active surveillance (AS).

MATERIAL AND METHODS

Data of 354 low-risk PCa patients who underwent RARP were retrospectively evaluated. Patients were divided into two groups: PSA fluctuation rate<9.5%/month (Group 1, n=192) and >9.5%/month (Group 2, n=162). Mainly compared parameters were GS upgrading, disease upstaging, biochemical recurrence (BCR) and surgical margin positivity (SMP) rates.

RESULTS

GS upgrading, disease upstaging and SMP were detected in 128 (36.2%), 56 (15.8%) and 42 (11.9%) patients, respectively. After a median follow-up of 46 months, BCR was observed in 40 (11.3%) patients. GS upgrading (41.1% vs. 30.2%, p=0.033), disease upstaging (19.8% vs. 11.1%, p=0.028), SMP (15.1% vs. 8%, p=0.035) and BCR development (15.6% vs. 6.2%, p=0.005) rates were statistically significantly higher in Group 1 than Group 2. In multivariate analysis, digital rectal examination positivity, the presence of two positive cores and low PSA fluctuation rate were found to be significant predictors of GS upgrading.

CONCLUSION

Low PSA fluctuation rate is associated with higher GS upgrading.

Improving the Specificity of PSA Screening with Serum and Urine Markers

PURPOSE OF REVIEW

Prostate cancer remains a significant public health burden. In order to decrease the morbidity and mortality associated with prostate cancer, serum prostate-specific antigen (PSA) screening has been used since the 1990s. However, there is concern for overdiagnosis of prostate cancer with widespread PSA screening, which could lead to overtreatment and its attendant morbidities.

RECENT FINDINGS

In order to avoid unnecessary biopsy and downstream effects including treatment of insignificant prostate cancer, a number of tests have been proposed to improve upon PSA screening. Increasing the specificity of prostate cancer screening above that of PSA testing should reduce the incidence of unnecessary prostate biopsy. However, an increase in specificity is associated with a decrease in sensitivity, so these tests must be balanced with the concern for missing the diagnosis of potentially significant disease. In this context, we present a review of six common biomarkers proposed to improve the specificity of prostate cancer screening-free PSA, prostate health index, 4Kscore, PCA3, Select MDx, and ExoDx Prostate(Intelliscore).

[What primary care physicians should know about new markers in prostate cancer]

The use of prostate-specific antigen as a diagnostic tool in the screening of prostate cancer is reflected in an increase in the incidence, an increase in diagnosis at initial stages, and an increase in radical therapies, even at the expense of over-treatment in some cases. It is known from the data collected in the literature that not every patient with high prostate-specific antigen needs a biopsy, and that not every patient diagnosed with prostate cancer needs treatment. With the new emerging prostate markers, we will try to improve the specificity of prostate-specific antigen in the grey area (4-10 ng/ml) should be improved. This should avoid unnecessary biopsies. The sensitivity in the detection of significant prostate cancer with low prostate-specific antigen should also be improved in an attempt to reduce the risk of over-treatment. On the other hand, prognostic biomarkers with genomic tests will help to choose the best therapeutic option for the patient.

Cost analysis of prostate cancer detection including the prostate health index (phi)

OBJECTIVE

To assess the economic impact of introducing the prostate health index (phi) for prostate cancer (PCa) detection.

METHODS

A total of 177 patients who presented in an academic institution with a tPSA between 2 and 10 ng/ml and underwent prostate biopsies within the 3 months were enrolled. With phi and tPSA thresholds of 43 and 4 ng/ml, respectively, probability for each branch of a decision tree model for PCa diagnosis and corresponding mean cost were estimated with "Monte Carlo" simulations. A sensitivity analysis was performed.

RESULTS

With a similar sensitivity, phi strategy increased positive predictive value by 13.9 points and negative predictive value by 31.6 points in comparison to tPSA strategy. Mean costs per patient with tPSA and phi strategies were €514 and €528, respectively, for a phi test price at 50€. One-way sensitivity analysis showed that phi strategy was less expensive (508€/patient) than tPSA strategy with a phi test price below 30€. In multi-criteria sensitivity analysis, PPV and the rates of positive phi and tPSA were the parameters with the largest impact on the final cost as opposed to the cost of the biopsy or imaging which have less influence. With an expected rate of positive phi test < 60%, tPSA strategy was more expensive than phi strategy.

CONCLUSIONS

The introduction of phi index in PCa detection would result in a significant clinical benefit compared to tPSA strategy. In our economic model, the phi strategy was equivalent or slightly more expensive than the current tPSA strategy.

Incorporating Biomarkers into the Primary Prostate Biopsy Setting: A Cost-Effectiveness Analysis

PURPOSE

We performed a cost-effectiveness analysis using the PHI (Prostate Health Index), 4Kscore®, SelectMDx™ and the EPI (ExoDx™ Prostate [IntelliScore]) in men with elevated prostate specific antigen to determine the need for biopsy.

MATERIALS AND METHODS

We developed a decision analytical model in men with elevated prostate specific antigen (3 ng/ml or greater) in which 1 biomarker test was used to determine which hypothetical individuals required biopsy. In the current standard of care strategy all individuals underwent biopsy. Model parameters were derived from a comprehensive review of the literature. Costs were calculated from a health sector perspective and converted into 2017 United States dollars.

RESULTS

The cost and QALYs (quality adjusted life-years) of the current standard of care, which was transrectal ultrasound guided biopsy, was $3,863 and 18.085, respectively. Applying any of the 3 biomarkers improved quality adjusted survival compared to the current standard of care. The cost of SelectMDx, the PHI and the EPI was lower than performing prostate biopsy in all patients. However, the PHI was more costly and less effective than the SelectMDx strategy. The EPI provided the highest QALY with an incremental cost-effectiveness ratio of $58,404 per QALY. The use of biomarkers could reduce the number of unnecessary biopsies by 24% to 34% compared to the current standard of care.

CONCLUSIONS

Applying biomarkers in men with elevated prostate specific antigen to determine the need for biopsy improved quality adjusted survival by decreasing the number of biopsies performed and the treatment of indolent disease. Using SelectMDx or the EPI following elevated prostate specific antigen but before proceeding to biopsy is a cost-effective strategy in this setting.

Genomic biomarkers in prostate cancer

Prostate cancer is the most common non-cutaneous cancer among men in the United States. In the last decade there has been a rapid expansion in the field of biomarker assays for diagnosis, prognosis, and treatment prediction in prostate cancer. The evidence base for these assays is rapidly evolving. With several commercial assays available at each stage of the disease, deciding which genomic assays are appropriate for which patients can be nuanced for physicians. In an effort to help guide these decisions in clinical practice, we aim to give an update on the current status of the biomarker field of prostate cancer.