Characteristics of prostate cancers detected at low PSA levels

Is prostatic adenocarcinoma detectable by urine cytology-A multicenter retrospective review

INTRODUCTION

Urine cytology is robust for the diagnosis of urothelial lesions, but data on the detection rates of prostatic adenocarcinoma in urine cytology is limited. In this study, a multicenter review was performed to define the clinical role of urine cytology in diagnosis of prostatic adenocarcinoma.

METHODS

Cytologic diagnoses of lower tract urine cytology specimens with histology-proven prostatic adenocarcinoma from three institutions, from a period of over two decades, were reviewed. Clinicopathological parameters-tumor grade, stage, histologic features, and preanalytical factors-prostate-specific antigen (PSA) level and lesion size, were retrieved and compared with cytologic diagnoses.

RESULTS

In total, 2115 urine cytology specimens from 1119 patients were retrieved. The atypia (or above/C3+) and suspicious (or above/C4+) rates were 19.48% and 3.36%. Bilobar and extracapsular involvement, lymphovascular invasion, Gleason score, and International Society of Urological Pathology grade were associated with a positive urine diagnosis (p < 0.05). The atypia (C3+) and suspicious (C4+) rates of urine cytology in patients with a PSA level of ≤4.0 ng/mL was paradoxically higher (p < 0.01), but PSA levels correlated positively with urine diagnosis at higher cutoffs (>10, >20, >50, >100 ng/mL). All these factors remained significant on multivariate analysis (p < 0.05), including a negative correlation with low-PSA (≤4.0 ng/mL, p = 0.001) and positive correlation with high-PSA (>20 ng/mL, p = 0.020). Lesion size and multifocality were not associated with urine cytology diagnosis (p > 0.05).

CONCLUSION

Urine cytology showed low sensitivity in detection of prostatic adenocarcinoma. Detection rates were largely positively correlated with PSA levels but not for lesion size nor multifocality, limiting its clinical utility.

The Transcriptomic Profiles of ESR1 and MMP3 Stratify the Risk of Biochemical Recurrence in Primary Prostate Cancer beyond Clinical Features

The molecular determinants of the heterogenic course of prostate cancer (PC) remain elusive. We aimed to determine the drivers predisposing to unfavorable PC outcomes anticipated by BCR events among patients of similar preoperative characteristics. The TCGA transcriptomic and clinical data of 497 PC individuals were used, stratified according to the risk of BCR by EAU-EANM-ESTRO-ESUR-SIOG. The relevance of the functional markers regarding BCR-free survival was examined by the cutp algorithm. Through UpSetR, subgroups of PC patients bearing an unfavorable signature were identified, followed by the hierarchical clustering of the major markers of the epithelial-to-mesenchymal transition (EMT). BCR-free survival was estimated with the Cox proportional hazards regression model. ESR1 significantly differentiated BCR-free survival, whereas AR did not. An elevation in KLK3 correlated with better prognosis, although PGR, KLK3, CDH1, and MMP3 predicted BCR better than the preoperative PSA level. Patients sharing an unfavorable profile of ESR1 and MMP3 together with lymph node status, Gleason score, T, and EAU risk groups were at a higher risk of BCR originating from mesenchymal features of PC cells. To conclude, we revealed an ESR1-driven unfavorable profile of EMT underpinning a worse PC trajectory. ESR1 may have a major role in PC progression; therefore, it could become a major focus for further investigations.

Machine learning classifiers can predict Gleason pattern 4 prostate cancer with greater accuracy than experienced radiologists

OBJECTIVE

The purpose of this study was: To test whether machine learning classifiers for transition zone (TZ) and peripheral zone (PZ) can correctly classify prostate tumors into those with/without a Gleason 4 component, and to compare the performance of the best performing classifiers against the opinion of three board-certified radiologists.

METHODS

A retrospective analysis of prospectively acquired data was performed at a single center between 2012 and 2015. Inclusion criteria were (i) 3-T mp-MRI compliant with international guidelines, (ii) Likert ≥ 3/5 lesion, (iii) transperineal template ± targeted index lesion biopsy confirming cancer ≥ Gleason 3 + 3. Index lesions from 164 men were analyzed (119 PZ, 45 TZ). Quantitative MRI and clinical features were used and zone-specific machine learning classifiers were constructed. Models were validated using a fivefold cross-validation and a temporally separated patient cohort. Classifier performance was compared against the opinion of three board-certified radiologists.

RESULTS

The best PZ classifier trained with prostate-specific antigen density, apparent diffusion coefficient (ADC), and maximum enhancement (ME) on DCE-MRI obtained a ROC area under the curve (AUC) of 0.83 following fivefold cross-validation. Diagnostic sensitivity at 50% threshold of specificity was higher for the best PZ model (0.93) when compared with the mean sensitivity of the three radiologists (0.72). The best TZ model used ADC and ME to obtain an AUC of 0.75 following fivefold cross-validation. This achieved higher diagnostic sensitivity at 50% threshold of specificity (0.88) than the mean sensitivity of the three radiologists (0.82).

CONCLUSIONS

Machine learning classifiers predict Gleason pattern 4 in prostate tumors better than radiologists.

KEY POINTS

• Predictive models developed from quantitative multiparametric magnetic resonance imaging regarding the characterization of prostate cancer grade should be zone-specific. • Classifiers trained differently for peripheral and transition zone can predict a Gleason 4 component with a higher performance than the subjective opinion of experienced radiologists. • Classifiers would be particularly useful in the context of active surveillance, whereby decisions regarding whether to biopsy are necessitated.

Prostate focal therapy: the rule or exception?

PURPOSE OF REVIEW

Prostate focal therapy has the potential to preserve urinary and sexual function while eliminating clinically significant cancer in a subset of men with low-volume, organ-confined prostate cancer. This systematic review aims to examine current evidence to determine the efficacy and safety of focal therapy for standard clinical application.

RECENT FINDINGS

Focal therapy reduces the rate of cancer progression and conversion to radical therapy in men on active surveillance for prostate cancer. As a strategy, success in focal therapy is heavily dependent on the use of imaging and targeted biopsies. Despite advances in these areas, there remains a small but significant risk of under-detecting clinically significant cancer. Similarly, under-estimation of tumor volume may contribute to infield recurrences and close attention must be paid to the ablation margin. Although long-term oncological outcomes remain lacking, focal therapy has a low complication rate, minimal impact on urinary continence and a moderate impact on erectile function.

SUMMARY

With the appropriate expertise in imaging, targeted biopsy and targeted ablation, focal therapy is a good option in men with low-intermediate risk cancer who are willing to maximize their urinary and sexual function. However, close posttreatment surveillance and the possibility of conversion to whole gland therapy must be accepted.

Telomerase RNA Expression and DNA Ploidy as Prognostic Markers of Prostate Carcinomas

Aims and Background

The objective of this study was to determine whether there was a correlation between telomerase RNA expression and DNA ploidy status with clinicopathological parameters and biochemical recurrence after radical prostatectomy.

Study Design

Telomerase RNA expression and DNA ploidy were evaluated in imprint smear samples obtained from 112 prostates after radical prostatectomy. The results were correlated with pathological stage, Gleason score and serum PSA.

Results

Positive telomerse RNA expression was detected in 67.8% of prostate carcinomas. The multiple linear regression model showed a statistically significance increase in telomerase RNA expression with increased Gleason score ( P <0.0001) and preoperative serum PSA values ( P = 0.0125). DNA ploidy status also varied significantly with Gleason score ( P <0.0001) and preoperative serum PSA values ( P = 0.0110). Five patients with diploid tumors and negative telomerase RNA expression developed a recurrence. However, recurrence was associated with DNA aneuploidy ( P = 0.001) as well as with high telomerase RNA overexpression ( P = 0.001).

Conclusions

We conclude that telomerase RNA expression and DNA ploidy could be additional markers in the field of prognosis of prostate carcinomas.

Actual lowering effect of metabolic syndrome on serum prostate-specific antigen levels is partly concealed by enlarged prostate: results from a large-scale population-based study

OBJECTIVES

To clarify the lowering effect of metabolic syndrome (MetS) on serum prostate-specific antigen (PSA) levels in a Chinese screened population.

SUBJECTS AND METHODS

A total of 45 540 ostensibly healthy men aged 55-69 years who underwent routine health check-ups at Beijing Shijitan Hospital between 2008 and 2015 were included in the study. All the men underwent detailed clinical evaluations. PSA mass density was calculated (serum PSA level × plasma volume ÷ prostate volume) for simultaneously adjusting plasma volume and prostate volume. According to the modified National Cholesterol Education Programme-Adult Treatment Panel (NCEP-ATP) III criteria, patients were dichotomized by the presence of MetS, and differences in PSA density and PSA mass density were compared between groups. Linear regression analysis was used to evaluate the effect of MetS on serum PSA levels.

RESULTS

When larger prostate volume in men with MetS was adjusted for, both PSA density and PSA mass density in men with MetS were significantly lower than in men without MetS, and the estimated difference in mean serum PSA level between men with and without MetS was greater than that before adjusting for prostate volume. In the multivariate regression model, the presence of MetS was independently associated with an 11.3% decline in serum PSA levels compared with the absence of MetS. In addition, increasing number of positive MetS components was significantly and linearly associated with decline in serum PSA levels.

CONCLUSION

The actual lowering effect of MetS on serum PSA levels was partly concealed by the enlarged prostate in men with MetS, and the presence of MetS was independently associated with lower serum PSA levels. Urologists need to be aware of the effect of MetS on serum PSA levels and should discuss this subject with their patients.

Revisiting tumour aneuploidy - the place of ploidy assessment in the molecular era

Chromosome instability (CIN) is gaining increasing interest as a central process in cancer. CIN, either past or present, is indicated whenever tumour cells harbour an abnormal quantity of DNA, termed 'aneuploidy'. At present, the most widely used approach to detecting aneuploidy is DNA cytometry - a well-known research assay that involves staining of DNA in the nuclei of cells from a tissue sample, followed by analysis using quantitative flow cytometry or microscopic imaging. Aneuploidy in cancer tissue has been implicated as a predictor of a poor prognosis. In this Review, we have explored this hypothesis by surveying the current landscape of peer-reviewed research in which DNA cytometry has been applied in studies with disease-appropriate clinical follow up. This area of research is broad, however, and we restricted our survey to results published since 2000 relating to seven common epithelial cancers (those of the breast; endometrium, ovary, and uterine cervix; oesophagus; colon and rectum; lung; prostate; and bladder). We placed particular emphasis on results from multivariate analyses to pinpoint situations in which the prognostic value of aneuploidy as a biomarker is strong compared with that of existing indicators, such as clinical stage, histological grade, and specific molecular markers. We summarize the implications of our findings for the prognostic use of ploidy analysis in the clinic and for the theoretical understanding of the role of CIN in carcinogenesis.

Dose painting to treat single-lobe prostate cancer with hypofractionated high-dose radiation using targeted external beam radiation: Is it feasible?

Targeted focal therapy strategies for treating single-lobe prostate cancer are under investigation. In this planning study, we investigate the feasibility of treating a portion of the prostate to full-dose external beam radiation with reduced dose to the opposite lobe, compared with full-dose radiation delivered to the entire gland using hypofractionated radiation. For 10 consecutive patients with low- to intermediate-risk prostate cancer, 2 hypofractionated, single-arc volumetric-modulated arc therapy (VMAT) plans were designed. The first plan (standard hypofractionation regimen [STD]) included the entire prostate gland, treated to 70 Gy delivered in 28 fractions. The second dose painting plan (DP) encompassed the involved lobe treated to 70 Gy delivered in 28 fractions, whereas the opposing, uninvolved lobe received 50.4 Gy in 28 fractions. Mean dose to the opposing neurovascular bundle (NVB) was considerably lower for DP vs STD, with a mean dose of 53.9 vs 72.3 Gy (p < 0.001). Mean penile bulb dose was 18.6 Gy for DP vs 19.2 Gy for STD (p = 0.880). Mean rectal dose was 21.0 Gy for DP vs 22.8 Gy for STD (p = 0.356). Rectum V70 (the volume receiving ≥70 Gy) was 2.01% for DP vs 2.74% for STD (p = 0.328). Bladder V70 was 1.69% for DP vs 2.78% for STD (p = 0.232). Planning target volume (PTV) maximum dose points were 76.5 and 76.3 Gy for DP and STD, respectively (p = 0.760). This study demonstrates the feasibility of using VMAT for partial-lobe prostate radiation in patients with prostate cancer involving 1 lobe. Partial-lobe prostate plans appeared to spare adjacent critical structures including the opposite NVB.

Tumor percentage but not number of tumor foci predicts disease-free survival after radical prostatectomy especially in high-risk patients

OBJECTIVE

To evaluate the predictive value of tumor volume (TV), tumor percentage (TP), and number of tumor foci (NF) in patients with prostate cancer. The prognostic relevance of TV, TP, and NF as predictors of biochemical recurrence (BCR) following radical prostatectomy (RPE) is controversial.

PATIENTS AND METHODS

The cohort consisted of 758 referred subjects who underwent RPE between 2000 and 2005 at the University of Muenster. The mean time of follow-up was 62 months. TV, TP, and NF were estimated visually with the assistance of a pathologic mapping grid for embedded whole-mount RPE specimens. In addition, TV and TP were assessed in a categorized fashion by using quartiles as cutoff points. Subgroup analyses for high- and low-risk patients using univariate and multivariate Cox proportional hazard analyses for BCR were performed.

RESULTS

TV, TP, and NF were strongly related to tumor stage, Gleason score, surgical margin status, and preoperative prostate-specific antigen (PSA). In univariate analysis, all pathologic parameters including TV, TP, and NF were predictive for BCR. In multivariate analysis, only TP, tumor stage, and PSA level were independent predictors. In subgroup analysis, TP was an independent predictor for BCR in the high-risk group but not in the low-risk group.

CONCLUSIONS

TP, but not TV or NF, was found to be an independent predictor for BCR in patients after RPE. TP seems to be more relevant in high-risk patients (i.e., any of the following: > pT2, Gleason score > 6, or PSA > 20 ng/ml).

Focal low-dose rate brachytherapy for the treatment of prostate cancer

Whole-gland low-dose rate (LDR) brachytherapy has been a well-established modality of treating low-risk prostate cancer. Treatment in a focal manner has the advantages of reduced toxicity to surrounding organs. Focal treatment using LDR brachytherapy has been relatively unexplored, but it may offer advantages over other modalities that have established experiences with a focal approach. This is particularly true as prostate cancer is being detected at an earlier and more localized stage with the advent of better detection methods and newer imaging modalities.

Report of a consensus meeting on focal low dose rate brachytherapy for prostate cancer

What's known on the subject? and What does the study add? Whole gland brachytherapy has been used to successfully treat prostate cancer but the protocol for focal therapy has not previously been established. The consensus findings provide guidance on patient selection for focal brachytherapy as well as recommendations for conducting therapy and patient follow-up. Low dose rate prostate brachytherapy is an effective treatment for localized prostate cancer. Recently, it has been considered for use in a focused manner whereby treatment is targeted only to areas of prostate cancer. The objective of focal brachytherapy is to provide effective cancer control for low-risk disease but with reduced genitourinary and rectal side-effects in a cost-effective way. We report on the outputs of a consensus meeting of international experts in brachytherapy and focal therapy convened to consider the feasibility and potential development of focal brachytherapy. A number of factors were considered for focal brachytherapy including optimal patient selection, disease characterization and localization, treatment protocols and outcome measures. The consensus meeting also addressed the design of a clinical trial that would assess the oncological outcomes and side-effect profiles resulting from focal brachytherapy.

Targeted high throughput sequencing in clinical cancer settings: formaldehyde fixed-paraffin embedded (FFPE) tumor tissues, input amount and tumor heterogeneity

Background

Massively parallel sequencing technologies have brought an enormous increase in sequencing throughput. However, these technologies need to be further improved with regard to reproducibility and applicability to clinical samples and settings.

Methods

Using identification of genetic variations in prostate cancer as an example we address three crucial challenges in the field of targeted re-sequencing: Small nucleotide variation (SNV) detection in samples of formalin-fixed paraffin embedded (FFPE) tissue material, minimal amount of input sample and sampling in view of tissue heterogeneity.

Results

We show that FFPE tissue material can supplement for fresh frozen tissues for the detection of SNVs and that solution-based enrichment experiments can be accomplished with small amounts of DNA with only minimal effects on enrichment uniformity and data variance.

Finally, we address the question whether the heterogeneity of a tumor is reflected by different genetic alterations, e.g. different foci of a tumor display different genomic patterns. We show that the tumor heterogeneity plays an important role for the detection of copy number variations.

Conclusions

The application of high throughput sequencing technologies in cancer genomics opens up a new dimension for the identification of disease mechanisms. In particular the ability to use small amounts of FFPE samples available from surgical tumor resections and histopathological examinations facilitates the collection of precious tissue materials. However, care needs to be taken in regard to the locations of the biopsies, which can have an influence on the prediction of copy number variations. Bearing these technological challenges in mind will significantly improve many large-scale sequencing studies and will - in the long term - result in a more reliable prediction of individual cancer therapies.

Suitability of PSA-detected localised prostate cancers for focal therapy: experience from the ProtecT study

Background:

Contemporary screening for prostate cancer frequently identifies small volume, low-grade lesions. Some clinicians have advocated focal prostatic ablation as an alternative to more aggressive interventions to manage these lesions. To identify which patients might benefit from focal ablative techniques, we analysed the surgical specimens of a large sample of population-detected men undergoing radical prostatectomy as part of a randomised clinical trial.

Methods:

Surgical specimens from 525 men who underwent prostatectomy within the ProtecT study were analysed to determine tumour volume, location and grade. These findings were compared with information available in the biopsy specimen to examine whether focal therapy could be provided appropriately.

Results:

Solitary cancers were found in prostatectomy specimens from 19% (100 out of 525) of men. In addition, 73 out of 425 (17%) men had multiple cancers with a solitary significant tumour focus. Thus, 173 out of 525 (33%) men had tumours potentially suitable for focal therapy. The majority of these were small, well-differentiated lesions that appeared to be pathologically insignificant (38–66%). Criteria used to select patients for focal prostatic ablation underestimated the cancer's significance in 26% (34 out of 130) of men and resulted in overtreatment in more than half. Only 18% (24 out of 130) of men presumed eligible for focal therapy, actually had significant solitary lesions.

Conclusion:

Focal therapy appears inappropriate for the majority of men presenting with prostate-specific antigen-detected localised prostate cancer. Unifocal prostate cancers suitable for focal ablation are difficult to identify pre-operatively using biopsy alone. Most lesions meeting criteria for focal ablation were either more aggressive than expected or posed little threat of progression.

Preoperative prediction of multifocal prostate cancer and application of focal therapy: review 2007

Prostate cancer is a leading malignancy among men. Early prostate cancer is most commonly treated with radical surgery and radiotherapy. In the era of prostate-specific antigen and newly emerging highly specific screening tests, a greater number of men are given a diagnosis earlier in life, and disease is more often confined. Less-invasive treatments, such as focal therapy, are becoming increasingly popular, yielding shorter hospital stays, faster recovery, and fewer complications. Potential drawbacks to focal therapy include the risk of incomplete treatment, which may result from missed cancer foci and inadequate ablation to target tissues. Furthermore, this approach is not universally applicable to all patients--for example, those who have periurethral and extraprostatic extension of the tumor may not benefit from focal treatment. This article reviews the importance of multifocal prostate cancer and the application of focal treatment.

Under diagnosis and over diagnosis of prostate cancer in a screening population with serum PSA 2 to 10 ng/ml

PURPOSE

Since the implementation of widespread serum total prostate specific antigen based screening, the risk of prostate cancer over diagnosis has become a concern. We evaluated the amount of possible over and under diagnosis of prostate cancer in an asymptomatic screening population with a total prostate specific antigen of 2.0 to 3.9 (lower range) and 4.0 to 10.0 ng/ml (higher range).

MATERIALS AND METHODS

A total of 680 patients with prostate cancer were included. Possible over diagnosis was defined as Gleason score less than 7, pathological stage pT2a and negative surgical margins. Under diagnosis was defined as pathological stage pT3 or greater, or positive surgical margins. Furthermore, insignificant tumors according to the Epstein criteria were evaluated in a small subset of patients for whom cancer volume information was available.

RESULTS

In the lower and higher total prostate specific antigen ranges there was an over diagnosis rate of 19.7% and 16.5%, and an under diagnosis rate of 18.9%* and 36.7%, respectively (p<0.05). In the prostate specific antigen range of 2.0 to 10.0 ng/ml combined the rates of over and under diagnosis were 17.6% and 30.3%, respectively. In addition, 8.7% of tumors with total prostate specific antigen 2.0 to 10.0 ng/ml met the Epstein criteria for insignificance.

CONCLUSIONS

These data show that the reported estimates of over diagnosis in the low total prostate specific antigen group are exaggerated in a screening population. Using our criteria prostate cancer under diagnosis occurs more frequently than over diagnosis in the total prostate specific antigen range of 4.0 to 10 ng/ml.

Prevalence and Clinical Significance of Prostate Cancer among 12,682 Men with Normal Digital Rectal Examination, Low PSA Levels (≤4 ng/ml) and Percent Free PSA Cutoff Values of 15 and 20%

AIM

To report prevalence and clinical relevance of T1c prostate cancers (PCa) in a selected population of men with serum prostate-specific antigen (PSA) levels < or =4 ng/ml enrolled in a multicenter case-finding protocol.

PATIENTS AND METHODS

A number of 16,298 men, aged 40-75 years, from the urology units they had been referred to, in most cases (81.6%) for lower urinary tract symptoms, were evaluated. Eighty percent of them had PSA < or =4 ng/ml and about 40% PSA < or =2.5 ng/ml. Patients with PSA < or =2.5 ng/ml and PSA between 2.6 and 4 ng/ml and with percent free PSA < or =15 and < or =20%, respectively, were eligible for biopsy; 28 patients refused it, and 11 patients were excluded from the study because of an abnormal digital rectal examination. Among 403 biopsied men, 82 had PSA < or =2.5 ng/ml (group A) and 321 PSA between 2.6 and 4 ng/ml (group B).

RESULTS

A PCa was found in 109 cases (27.0%): 21 in group A and 88 in group B. 48 (44%) of the 109 patients with a PCa underwent radical prostatectomy: all cancers had a volume >0.5 cm(3), and 41% had a final Gleason sum > or =7; the PCa was organ confined in 34 patients (70.8%) and locally advanced in 14 patients (29.1%), and in 12 patients (25%) positive surgical margins were found.

CONCLUSIONS

Using percent free PSA thresholds of 15 and 20%, 25.6% of the men with PSA < or =2.5 ng/ml and 27.4% of the men with PSA between 2.6 and 4 ng/ml were found to have a PCa, respectively. Most of these cancers, when submitted to radical prostatectomy, were found to be clinically significant. As these cancers are mostly organ confined, these patients are ideal candidates for curative nerve-sparing surgery.

Should Men with Serum Prostate-Specific Antigen ≤4 ng/ml and Normal Digital Rectal Examination Undergo a Prostate Biopsy?

The clinical significance of a prostate cancer (PCa) cannot be determined solely by tumor volume (< or =0.5 cm(3)), as small tumors of higher Gleason grade and tumors occurring in younger men may become clinically significant even though the initial volume at diagnosis is small. A certain number of these minimal cancers are likely to remain clinically insignificant; however, it is unpredictable how many can progress beyond the curable stage by the time there is a rise in serum prostate-specific antigen (PSA) values. Compared to clinically detected PCa, PCa detected exclusively by PSA screening (clinical stage T1c) are less likely to be advanced but no more likely to be insignificant in terms of volume, pathologic stage, and Gleason pattern. Only 10-15% of PSA-detected cancers have the features of PCa found at autopsy or in cystoprostatectomy specimens. Actually, 25-30% of PCa are detected with PSA values between 2.5 and 4 ng/ml, and most of these cancers are clinically significant. Evidence from both retrospective and longitudinal studies has shown that the risk of a PCa is dependent on the patient's age and the initial serum PSA. This allows an individualized approach to PCa screening programs, and PSA cutoff values for biopsy indication may be lowered in selected patients.

Evidence-based medicine in prostate cancer: where do we stand in 2006?

PURPOSE OF REVIEW

A majority of medical decisions relating to the diagnosis, prognosis, and therapy of prostate cancer are based on low levels of evidence. This article reviews the recommendations of currently available evidence-based practice guidelines that relate to the management of patients with newly diagnosed prostate cancer. The article further introduces a selection of recent studies that are relevant to the evidence-based patient care.

RECENT FINDINGS

Updated clinical practice guidelines on the management of prostate-cancer patients provide an evidence-based summary of the literature and have recently been made available through the National Cancer Center Network and the European Urological Association. In addition, several recent high-quality studies have made major contributions to our knowledge of the natural history and therapy of prostate cancer.

SUMMARY

The efforts of professional associations to generate evidence-based guidelines are reflective of an increased awareness that the care of prostate cancer should--to the greatest possible extent--be evidence-based. Practicing urologists should seek to become involved in the evidence-based medicine process by supporting the accrual to high-quality clinical trials, demanding the highest standards to the timely and unbiased dissemination of research findings and ultimately, strive to apply the best available evidence to the care of individual patients.

The significance of tumor heterogeneity for prediction of DNA ploidy of prostate cancer

OBJECTIVE

In a previous study, we mapped the ploidy heterogeneity of prostate cancer using flow cytometry in 676 tumor samples from 50 radical prostatectomy specimens. Ploidy heterogeneity was common (42% of tumors) and was found in all non-diploid tumors. The volume of non-diploid tumor was estimated and found to predict extra-prostatic extension and seminal vesicle invasion. The aim of this study was to evaluate the impact of tumor heterogeneity on preoperative ploidy assessment.

MATERIAL AND METHODS

In 50 men at least six core biopsies were taken before prostatectomy. Sections from biopsies with cancer were Feulgen-stained for image cytometry. After exclusion of biopsies with insufficient material, 123 histograms from 48 men (mean 2.6; range 1-7) remained for analysis.

RESULTS

In 32 men, biopsies were diploid. In 16 men, at least one biopsy was non-diploid (14 tetraploid, two aneuploid) and 10 of them also had diploid biopsies. In 34 men (71%), the prostatectomy specimens were correctly predicted as being either diploid (48%) or non-diploid (23%). The sensitivity and specificity of biopsies for predicting non-diploid cancer were 55% and 82%, respectively, and the positive and negative predictive values were 69% and 72%, respectively. The ploidy status of tumors with and without ploidy heterogeneity was correctly predicted in 55% and 82% of cases, respectively (p=0.04). Biopsies underestimated ploidy in 9/20 tumors (45%) with heterogeneous ploidy status. Underestimation mainly occurred when one or two cores were analyzed.

CONCLUSIONS

Preoperative prediction of the ploidy status of prostate cancer is hampered by tumor heterogeneity. Analysis of multiple biopsies is important for correct preoperative ploidy estimation.

Detection rates and biologic significance of prostate cancer with PSA less than 4.0 ng/mL: observation and clinical implications from Tyrol screening project

OBJECTIVES

To investigate the prostate cancer (PCa) detection rates and Gleason scores in patients with serum prostate-specific antigen (PSA) levels of 2.0 to 3.9 ng/mL and 4.0 to 10 ng/mL (free PSA 18% or less), in a population-based screening project. With the use of prostate-specific antigen (PSA) screening, more PCa is being diagnosed at PSA values of less than 4 ng/mL.

METHODS

A total of 3446 consecutive screening volunteers with a PSA level of 2.0 to 10.0 ng/mL (free PSA 18% or less) were assessed. Ten systematic prostate biopsies and an additional five Doppler-enhanced targeted biopsies were performed on the basis of age-specific PSA reference ranges. The cumulative frequency of detection and the Gleason scores were analyzed.

RESULTS

The PCa detection rate for patients with a PSA value of 2.0 to 3.9 ng/mL (n = 1522, group 1) and 4.0 to 10.0 ng/mL (n = 1924, group 2) was 21% (n = 320) and 30% (n = 572), respectively. Of the PCa cases detected, 37% were in men with a PSA level of 2 to 4 ng/mL. Statistically significant differences were found in age and prostate volume between groups 1 and 2, with patients in the lower PSA group younger and having a smaller mean prostate volume (P = 0.0001). Of 313 patients with PCa and a PSA value of 2 to 3.9 ng/mL, 24% had a Gleason score of 7 or greater compared with 33% of 560 patients with a PSA value of 4.0 to 10.0 ng/mL (P = 0.004).

CONCLUSIONS

Our data suggest that in a screening population, more than one third of PCa cases in men with a PSA level of 2 to 10 ng/mL will occur in those with a PSA value of 2 to 3.9 ng/mL. Also, PCa cases with a low PSA level occur in younger patients and at lower stages with a smaller prostate volume.

The effect of percentage free prostate-specific antigen (PSA) level on the prostate cancer detection rate in a screening population with low PSA levels

OBJECTIVE

To evaluate the prostate cancer detection rate at low total prostate-specific antigen (tPSA) ranges of 2.6-4 and 4.1-10 ng/mL, according to different percentage free (f/t) PSA levels in a screening population.

SUBJECTS AND METHODS

In all, 1809 consecutive screening volunteers with a tPSA level of 2.6-10.0 ng/mL were assessed. Ten systematic ultrasonography-guided prostate biopsies and, since 2000, an additional five Doppler-enhanced targeted biopsies were taken on the basis of age-specific tPSA reference ranges. We analysed the detection rate of prostate cancer according to f/tPSA ranges of 0-9%, 10-14%, 15-18% and >18%.

RESULTS

The detection rates for the subgroups with tPSA levels of 2.6-4.0 and 4.1-10.0 ng/mL were 20.2% and 27.0%, respectively. The cancer detection rate in the first group (2.6-4.0 ng/mL) at 0-10% fPSA was 22.9%, and that in the second group (4.1-10.0 ng/mL) at 0-10% was 36.9%. There were significant differences between these groups. If the f/tPSA was 10-15%, the cancer detection rate for the two groups were 22.6% and 32.5%, respectively (P < 0.05). There was no statistically significant difference in the cancer detecting rates at an f/tPSA of 15-18% or >18%.

CONCLUSION

There is a statistically significantly higher cancer detection rate when the f/tPSA is <15% than in groups of men with a f/tPSA of >15% in screening population assessed primarily using tPSA level.

Use of effective core volume obtained from transrectal biopsies for predicting target tumor volume

OBJECTIVES

To evaluate, in a retrospective review, whether the concept of effective core volume is useful for predicting the volume of a tumor focus identified by transrectal needle biopsy of the prostate gland.

METHODS

The tumor volume range was estimated according to the concept of an effective core volume using the numbers of total and positive biopsy cores from the peripheral zone and peripheral zone prostate volume in 32 patients with prostate cancer with one to three cancer-positive cores who only underwent radical prostatectomy after transrectal prostate biopsy. The estimated tumor volume was compared with the actual tumor volume as determined by pathologic examination of whole mount sections of the prostatectomy specimens.

RESULTS

In the 32 patients, the actual tumor volume was within the range determined by the effective core volume concept in 24 patients (75.0%), although 4 (12.5%) had a smaller focus and 4 (12.5%) a larger focus than estimated. Overall accuracy improved up to 84.4% (27 of 32) if 5% safety margins were applied to the range determined by the effective core volume concept. In particular, the accuracy was 87.5% (14 of 16) in patients with one positive core after transrectal systemic biopsy.

CONCLUSIONS

The effective core volume can be used to predict the volume of prostate cancer with acceptable accuracy. It can provide an assumed maximal tumor volume and valuable information for clinical decision making of the treatment strategy, particularly in cases with one positive core.

Use of thymosin beta15 as a urinary biomarker in human prostate cancer

BACKGROUND

Additional prostate cancer (CaP) biomarkers are needed to increase the accuracy of diagnosis and to identify patients at risk of recurrence. In tissue-based assays, thymosin beta15 (Tbeta15) has been linked to an aggressive CaP phenotype and correlated with future tumor recurrence. We hypothesized that Tbeta15 may have clinical utility in biological fluids.

METHODS

Tbeta15 was measured in urine from CaP patients; untreated (N = 61), prostatectomy (RP, N = 46), androgen deprivation therapy (ADT, N = 14) and control groups; normal (N = 52), genitourinary carcinoma (N = 15), non-malignant prostate disease (N = 81), and other urology (N = 73). We evaluated the utility of urinary Tbeta15 for CaP diagnosis, alone or in combination with prostate-specific antigen (PSA), and the relationship to CaP progression.

RESULTS

A normal threshold of 40 (ng/dl)/(mug_protein/mg_creatinine) was defined using receiver operating characteristic analysis and marked the 19th centile for age-matched controls. The proportion of untreated CaP patients with urinary Tbeta15 above the threshold was significantly higher than normal and genitourinary disease controls (P < 0.001). RP caused urinary Tbeta15 to drop significantly (P = 0.005). Pre-surgery Tbeta15 concentrations greater than the normal threshold may confer greater risk of CaP recurrence. Relative to normal controls, patients receiving ADT for aggressive CaP were 12 times more likely to have elevated urinary Tbeta15 (P = 0.001, 95% CI = 2.8, 51.8). Combining PSA and Tbeta15 (PSA > 4, or PSA > 2.5, Tbeta15 > 40, or PSA = 2.5, Tbeta15 > 90) provided the same sensitivity as a 2.5 ng/ml PSA cutoff, but markedly improved diagnostic specificity.

CONCLUSIONS

We report that Tbeta15 is a urinary biomarker for CaP and suggest that Tbeta15, in combination with PSA, can be used to improve both the sensitivity and specificity of CaP diagnosis.

Incidence of Prostate Cancer in Sicily: Results of a Multicenter Case-Findings Protocol

OBJECTIVE

To establish the incidence of prostate cancer (PCa) in Sicily in patients who entered an early detection protocol.

METHODS

From February 2002 to February 2004, 16,298 subjects aged 40-75 entered the protocol. Patients with suspicious DRE, PSA>10 ng/ml, PSA<or=2.5 ng/ml, from 2.6 to 4 ng/ml or from 4.1 to 10 ng/ml with F/T PSA of <or=15%, <or=20% and <or=25% respectively underwent needle biopsy according to an extensive protocol.

RESULTS

3266 patients were eligible for biopsy; PSA was <or=4 in 12.7% and <or=10 ng/ml in 63.9% of patients. A PCa was found in 1171 cases (36.9%) with a relationship between PCa incidence and PSA and age respectively (chi2-test, p<0.0001); 51.8% of patients with PCa had a PSA<10 and 8.8% a PSA<4 ng/ml; 49% were clinically staged as T1c. The estimated odds ratios for each age group showed increased risk for PCa in the fourth decade with PSA between 2.6 and 4 ng/ml (12.5 times higher) and in the fifth decade with PSA between 4.1 and 10 ng/ml (6.2 times higher).

CONCLUSIONS

Age and serum PSA levels are the major risk factors for PCa. On their basis it is possible to modulate the most suitable timing for early diagnosis in individual patients.

Diagnóstico del cáncer de próstata mediante biopsia ampliada de 24 cilindros

OBJECTIVE

To determine the diagnostic performance of extended prostatic biopsy (PB) in prostate cancer (PC) and variables affecting positivity.

MATERIALS AND METHODS

Patients (n = 147) underwent 24 cylinder PB at the Arquitecto Marcide Hospital, Ferrol, La Coruña, between December 2002-September 2004. Inclusion criteria were the following: patients aged < or = 70 with one or more negative PB or aged < or = 75 with two or more negative PB. An univariate analysis was carried out using the chi-squared test for the qualitative variables and the t-Student and U Mann-Whitney tests in the case of the quantitative variables, plus a logistical regression analysis in order to identify those variables related to the extended PB positivity.

RESULTS

60 patients (40.82%) were identified as having PC. Significant differences were observed in prostatic volume, free/total PSA ratio in the initial PB, free/total PSA ratio in the extended PB, PSA-density in the extended PB as well as the existence of chronic prostatitis in previous PB. During the multivariate analysis it was found that the PSA-density and the presence of chronic prostatitis in previous PB independently predicted the positivity of the extended PB.

CONCLUSIONS

Extended PB allows for the detection of PC in 40.82% of patients with previous negative PB. The increase in PSA density is associated with a greater probability of PC, whilst the existence of chronic prostatitis in prior PB significantly reduces the probability of PC in the extended PB.

Biochemical outcome after radical prostatectomy among men with normal preoperative serum prostate-specific antigen levels

BACKGROUND

Recent studies have shown that a significant number of men with normal prostate-specific antigen (PSA) levels have prostate carcinoma. Whether malignancies in such men are associated with better outcomes is unclear. The authors compared the risk of biochemical failure after radical prostatectomy (RP) between men with normal PSA levels and men with elevated PSA levels.

METHODS

Data were examined from 1582 men who underwent RP between 1988 and 2002 at 1 of 5 equal-access medical centers. Patients were segregated into groups based on serum PSA levels (with stratification according to age-specific reference ranges). Clinical and pathologic characteristics and biochemical outcome data were compared across groups using analyses of variance, log-rank tests, and Cox proportional hazards analysis.

RESULTS

Men who had normal PSA levels had significantly fewer high-grade tumors compared with men who had higher PSA levels (P < 0.001). The former group had a significantly decreased incidence of positive surgical margins, extracapsular disease, seminal vesicle invasion, and lymph node involvement (P < 0.001). On multivariate analysis, only serum PSA level (P < 0.001) and biopsy Gleason score (P < 0.001) predicted the time to disease recurrence. When only men with serum PSA levels < 10 ng/mL were examined, PSA level treated as a continuous variable remained a significant predictor of time to biochemical failure (P = 0.02).

CONCLUSIONS

Men who had normal PSA levels had significantly fewer high-grade tumors and significantly better biochemical outcomes after undergoing RP compared with men who had elevated PSA levels. Overall, men with normal PSA levels who undergo RP represent a favorable risk group.