An abnormal digital rectal examination is an independent predictor of Gleason > or =7 prostate cancer in men undergoing initial prostate biopsy: a prospective study of 790 men

The additive value of mpMRI on prostate cancer detection: Comparison between patients with and without a suspicious digital rectal examination (DRE)

PURPOSE

Diagnosis of prostate cancer (CaP) is based on digital rectal examination (DRE) and/or elevated prostate specific antigen (PSA) level. This approach lacks sensitivity and specificity and is associated with many negative biopsies, high rate of diagnosing clinically insignificant disease and lacks accuracy to predict clinically significant (CS) cancer. The addition of multiparametric magnetic resonance imaging (mpMRI) before prostate biopsy reduces the detection of low-grade tumors while improving the detection of CS CaP. Most studies that evaluated mpMRI performance did not separate the DRE status of the examined patients. Therefore, the aim of our study is to investigate whether mpMRI provides similar advantages in detection of CaP according to the DRE findings.

MATERIALS AND METHODS

This prospective study included patients with clinically suspected CaP that were referred to MRI-fusion biopsy from 2014 to 2019. All patients had mpMRI of the prostate with an index lesion of PIRADS ≥3. Analysis was done comparing systemic and targeted biopsy. Patients were divided into two groups according to the DRE findings (positive or negative DRE) and the primary outcomes were compared between the 2 study groups: detection rate of CaP and the detection rate of CS disease defined as Gleason score ≥ 7.

RESULTS

The final study cohort included 86 patients: 47 with negative DRE and 39 with positive DRE. Overall cancer detection rate was higher in patients with a positive DRE (70.3% vs 48.9%, P <0.05). In the region of interest a higher overall detection rate and of CS disease was found in those with abnormal DRE (51.3% vs. 40.4% and 48.6% vs. 34.0% respectively). The systematic biopsy analysis showed an overall lower detection rate in the negative DRE group (8.5% vs. 18.9 %). The targeted biopsies detected more cancer and significant tumors per core in patients with positive DRE (29.2% vs. 18.5% and 22.1% vs. 14.5% respectively).

CONCLUSIONS

Patients submitted to fusion biopsy and have a positive DRE are diagnosed more often with CaP, have higher grade disease and larger tumors. In patients suspicious for CaP and having a significant lesion on mpMRI one should combine targeted and systematic biopsy regardless of the DRE status.

Incidence of metastasis and prostate-specific antigen levels at diagnosis in Gleason 3+4 versus 4+3 prostate cancer

Aims:

The aim is to assess for a difference in the incidence of metastasis (IM) and prostate-specific antigen (PSA) levels at diagnosis in patients with Gleason score (GS) 3+4 versus 4+3 prostate cancer using a large veterans affairs database.

Subjects and Methods:

A retrospective review of 1402 medical records from 5 VA hospitals was conducted. The study period was from 2009 to 2014. Primary endpoints were IM and PSA levels at diagnosis. A secondary endpoint was overall survival.

Statistical Analysis Used:

Chi-square tests for categorical variables, Student's t-test for continuous, normally distributed variables, and rank sum tests for continuous nonnormally distributed variables.

Results:

There were 1050 patients with GS3+4 and 352 with GS4+3. There were no differences in sociodemographic and clinical characteristics of the study population. PSA at the time of diagnosis was significantly higher in the GS4+3 patients compared to GS3+4 (18.0 vs. 11.4, respectively; P < 0.001). The IM at diagnosis was higher in the GS4+3 patients (10/352) compared to GS3+4 (9/1041) (2.8% vs. 0.9%; P = 0.005). In an adjusted model, GS4+3 was associated with higher PSA, higher IM at diagnosis. There was no difference in overall survival between the 2 groups though a 23% reduction in overall survival in the GS4+3 was noted (P = 0.53).

Conclusions:

Our results indicate that patients with GS4+3 prostate cancers have higher PSA levels at diagnosis. GS4+3 is associated with 3-fold increased risk of IM at diagnosis than GS3+4 though the overall incidence is low. Further research is needed to assess whether GS4+3 patients need routine staging imaging investigations at the time of diagnosis similar to patients with higher Gleason scores (GS ≥8).

Use of Digital Rectal Examination as an Adjunct to Prostate Specific Antigen in the Detection of Clinically Significant Prostate Cancer

PURPOSE

Guidelines from the NCCN^® (National Comprehensive Cancer Network®) advocate digital rectal examination screening only in men with elevated prostate specific antigen. We investigated the effect of prostate specific antigen on the association of digital rectal examination and clinically significant prostate cancer in a large American cohort.

MATERIALS AND METHODS

We evaluated the records of the 35,350 men who underwent digital rectal examination in the screening arm of the Prostate, Lung, Colorectal and Ovarian Cancer Screening trial for the development of clinically significant prostate cancer (Gleason 7 or greater). Followup was 343,273 person-years. The primary outcome was the rate of clinically significant prostate cancer among men with vs without suspicious digital rectal examination. We performed competing risks regression to evaluate the interaction between time varying suspicious digital rectal examination and prostate specific antigen.

RESULTS

A total of 1,713 clinically significant prostate cancers were detected with a 10-year cumulative incidence of 5.9% (95% CI 5.6-6.2). Higher risk was seen for suspicious vs nonsuspicious digital rectal examination. Increases in absolute risk were small and clinically irrelevant for normal (less than 2 ng/ml) prostate specific antigen (1.5% vs 0.7% risk of clinically significant prostate cancer at 10 years), clinically relevant for elevated (3 ng/ml or greater) prostate specific antigen (23.0% vs 13.7%) and modestly clinically relevant for equivocal (2 to 3 ng/ml) prostate specific antigen (6.5% vs 3.5%).

CONCLUSIONS

Digital rectal examination demonstrated prognostic usefulness when prostate specific antigen was greater than 3 ng/ml, limited usefulness for less than 2 ng/ml and marginal usefulness for 2 to 3 ng/ml. These findings support the restriction of digital rectal examination to men with higher prostate specific antigen as a reflex test to improve specificity. It should not be used as a primary screening modality to improve sensitivity.

PCA3 as a second-line biomarker in a prospective controlled randomized opportunistic prostate cancer screening programme

OBJECTIVES

PCA3 performance as a single second line biomarker is compared to the European Randomised Study of Screening for Prostate Cancer risk calculator model 3 (ERSPC RC-3) in an opportunistic screening in prostate cancer (PCa).

MATERIAL AND METHODS

5,199 men, aged 40-75y, underwent prostate-specific antigen (PSA) screening and digital rectal examination (DRE). Men with a normal DRE and PSA ≥3ng/ml had a PCA3 test done. All men with PCA3 ≥35 underwent an initial biopsy (IBx) -12 cores-. Men with PCA3 <35 were randomized 1:1 to either IBx or observation. We compared them to those obtained with ERSPC RC-3.

RESULTS

PCA3 test was performed on 838 men (16.1%). In PCA3(+) and PCA3(-) groups, global PCa detection rates were 40.9% and 14.7% with a median follow-up (FU) of 21.7 months (P<.001). In the PCA3(+) arm (n=301, 35.9%), PCa was identified in 115 men at IBx (38.2%). In the randomized arm, 256 underwent IBx and PCa was found in 46 (18.0%) (P<.001). The biopsy-sparing potential would have been 64.1% as opposed to 76.6% if we had used ERSPC RC-3. However, the estimated false negative cases for HGPCa would have been reduced by 37.1% (89 to 56 patients). Moreover, if we had applied PCA3-35 to avoid IBx, 14.7% PCa and 9.1% of clinical significant PCa patients would not have been diagnosed during this FU.

CONCLUSIONS

When PCA3-35 is used as a second-line biomarker when PSA ≥3ng/ml and DRE is normal, IBx could be avoided in 12.5% less than if ERSPC RC-3 is used and would reduce the false negative cases by 36.2%. At a FU of 21.7 months, this dual protocol would miss 9.1% of clinically significant PCa, so strict FU is mandatory with established biopsy criteria based on PSA and DRE in cases with PCA3 <35.

Is it time to abandon the digital rectal examination? Lessons from the PLCO Cancer Screening Trial and peer-reviewed literature

OBJECTIVE

In 2012 the US Preventive Services Task Force released recommendations against prostate specific antigen (PSA) based screening for prostate cancer, but did not fully address screening via digital rectal exam (DRE). As such, many practitioners continue to perform DRE in attempts to identify men with clinically significant prostate cancer (CSPC). This study seeks to determine the value of DRE in detecting CSPC in the era of PSA-based screening.

METHODS

Data from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Screening Trial, a nationwide population-based study evaluating cancer screening programs and their impact on cancer mortality, was analyzed for PSA, DRE, and cancer status. In the screening arm of the PLCO, 38,340 men received annual PSA and DRE examinations for the first 3 years. Those with an abnormal test result were referred to their individual care provider for biopsy. The ability of DRE to detect CSPC, defined as intermediate risk or higher based on National Comprehensive Cancer Network guidelines and age ≤75, was evaluated in the context of both normal and abnormal PSA.

RESULTS

A total of 5064 men had abnormal DRE in the setting of normal PSA, of whom 99 (2%) were diagnosed with CSPC. When both PSA and DRE were abnormal, 218 (20%) participants were diagnosed with CSPC (RR = 2.06 [1.78-2.39] versus abnormal PSA alone).

CONCLUSIONS

DRE screening in the setting of normal PSA captured an additional 2% of men with CSPC. This incremental gain suggests that routine DRE screening subjects a large number of men to invasive, potentially uncomfortable examinations for relatively minimal gain. Key limitations: Our conclusions are based on data derived from the PLCO study which has been criticized on the basis of inconsistent biopsies following positive screening tests, lack of end of study biopsies to determine population disease burden, and low numbers of black men.

Patients treated with radical prostatectomy with positive digital rectal examination findings in the intermediate-risk group are prone to PSA recurrence

The present study aimed to evaluate the possibility of performing radical prostatectomy (RP) alone to achieve a radical cure for prostate cancer in the intermediate-risk group. Samples were collected from 638 Japanese patients who underwent antegrade RP between August 1998 and May 2013; subsequently, 157 patients were excluded. According to the D'Amico criteria, the low-, intermediate- and high-risk groups comprised 107, 222 and 152 patients, respectively. The 5-year prostate-specific antigen (PSA) failure-free survival rates in the low-, intermediate-, and high-risk groups were 96.5, 88.9 and 72.6%, respectively (P<0.001; degrees of freedom=2). In the intermediate-risk group, the difference in PSA failure-free survival between the 0<PSA≤10 and 10<PSA≤20 ng/ml, and the biopsy Gleason score 6 and 7 groups were not statistically significant, according to the log-rank test (P=0.2266 and P=0.1329, respectively). However, the difference in PSA failure-free survival between the clinical tumor stage (cT)1c and cT2a/b groups was statistically significant based on the log-rank test (P<0.0001). The results of the multivariate analysis revealed that, of the preoperative characteristics, only the cT was a significant predictor in patients with and without PSA failure (P<0.001). Therefore, patients classified into the intermediate-risk group with cT2a/b stage, according to positive digital rectal examination findings, and are not considered to be likely to achieve a complete cure with RP surgery alone. In summary, for patients meeting these criteria in the intermediate-risk group, RP surgery alone is likely to be insufficient, and other additional treatments may be considered subsequent to RP.

Digital rectal examination in primary care is important for early detection of prostate cancer: a retrospective cohort analysis study

BACKGROUND

Currently, there is no standardised screening for prostate cancer in Europe. Assessment of risk is opportunistically undertaken in consultation with the GP or urologist. Evaluation of the prostate gland consists of a prostate-specific antigen (PSA) serum level and a digital rectal examination (DRE) of the gland. DRE is an essential part of the assessment that can independently predict prostate cancer in the setting of a normal PSA level.

AIM

To evaluate the clinical usefulness of the DRE in general practice and urology clinics, and to ascertain its positive predictive value and sensitivity.

DESIGN AND SETTING

A retrospective analysis study of a cohort of Irish men who underwent TRUS guided biopsy of the prostate in a single Irish tertiary referral centre, despite a normal PSA level. Patients were identified from a Rapid Access Prostate Clinic patient database. Pathological biopsy results were correlated with clinical DRE findings.

METHOD

Patient demographics, PSA levels, and DRE findings from a prospectively established database and hospital data systems from May 2009 to October 2013 were analysed.

RESULTS

Of 103 men referred over a 53-month period with a normal age-adjusted PSA level, 67% were referred on the basis of an abnormal DRE alone. Thirty-five per cent of males with a normal PSA had prostate cancer. DRE alone had a sensitivity and specificity of 81% and 40% respectively in diagnosing prostate cancer, with a positive predictive value of 42%. Seventy-six per cent of these men had high-grade disease.

CONCLUSION

DRE is a key part of the assessment for prostate cancer. It can independently identify patients at risk of prostate cancer, with a substantial proportion of these having clinically significant disease requiring treatment. This study reinforces the importance of DRE in the primary care setting in the assessment for prostate cancer. An abnormal DRE, even in the setting of a normal PSA level, necessitates referral.

Contemporary outcomes in the detection of prostate cancer using transrectal ultrasound-guided 12-core biopsy in Singaporean men with elevated prostate specific antigen and/or abnormal digital rectal examination

Objective

Despite being the third commonest cancer in Singaporean men, there is a dearth of basic data on the detection rate of prostate cancer and post-procedure complication rates locally using systematic 12-core biopsy. Our objective is to evaluate prostate cancer detection rates using 12-core prostate biopsy based on serum prostate specific antigen (PSA) levels and digital rectal examination (DRE) findings in Singaporean men presenting to a single tertiary centre. The secondary objective is to evaluate the complication rates of transrectal prostate biopsies.

Methods

We retrospectively examined 804 men who underwent first transrectal-ultrasound (TRUS) guided 12-core prostate biopsies from January 2012 to April 2014. Prostate biopsies were performed on men presenting to a tertiary institution when their PSA levels were ≥4.0 ng/mL and/or when they had suspicious DRE findings.

Results

Overall prostate cancer detection rate was 35.1%. Regardless of DRE findings, patients were divided into four subgroups based on their serum PSA levels: 0–3.99 ng/mL, 4.00–9.99 ng/mL, 10.00–19.99 ng/mL and ≥20.00 ng/mL and their detection rates were 9.5%, 20.9%, 38.4% and 72.3%, respectively. The detection rate of cancer based on suspicious DRE findings alone was 59.2% compared to 36.5% based on serum PSA cut-off of 4.0 ng/mL alone. The post-biopsy admission rate for sepsis was 1.5%.

Conclusion

In conclusion, using contemporary 12-core biopsy methods, the local prostate cancer detection rate based on serum PSA and DRE findings has increased over the past decade presumably due to multiple genetic and environmental factors. Post-biopsy sepsis remains an important complication worldwide.

A tale of two trials: The impact of 5α-reductase inhibition on prostate cancer (Review)

The use of 5α-reductase inhibitors (5α-RIs) as prostate cancer chemoprevention agents is controversial. Two large randomized trials, the Prostate Cancer Prevention Trial (PCPT) and the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) Trial, have both shown a decreased incidence of prostate cancer in patients administered with 5α-RIs. Both studies showed, however, an increased risk of higher-grade prostate cancer. Numerous studies have since analyzed the inherent biases in these landmark studies and have used mathematical modeling to estimate the true incidence of prostate cancer and the risk for high-grade prostate cancer in patients undergoing 5α-RI treatment. All primary publications associated with the PCPT and REDUCE studies were reviewed in detail. Pertinent references from the above publications were assessed and a literature search of all published articles associated with PCPT, REDUCE or 5α-RIs as chemopreventative agents through October 2013 was performed using Pubmed/Medline. PCPT and REDUCE both showed a significant decrease in the incidence of prostate cancer following the administration of 5α-reductase inhibitor, as compared with placebo, suggesting that 5α-RIs may be effective agents for prostate cancer chemoprevention. Inherent biases in the design of these two studies may have caused an artificial increase in the number of high-grade cancers reported. Mathematical models, that integrated data from these trials, revealed neither an increased nor decreased risk of high-grade disease when taking these biases into consideration. Moderately strong evidence exists that 5α-RIs may reduce the risk of prostate cancer. PCPT and REDUCE showed a decreased prevalence of prostate cancer in patients taking 5α-RIs. Urologists should have a working knowledge of these studies and discuss with patients the risks and benefits of 5α-RI treatment. Further studies to evaluate the cost-effectiveness of chemoprevention with 5α-RIs and appropriate patient selection are warranted.

Optimizing prostate cancer screening; prospective randomized controlled study of the role of PSA and PCA3 testing in a sequential manner in an opportunistic screening program

OBJECTIVES

To reduce unnecessary biopsies (Bx) in an opportunistic screening programme of prostate cancer.

MATERIAL AND METHODS

We perform a prospective evaluation of PCA3 as a second line biomarker in an opportunistic screening for prostate cancer (PCa). From September-2010 until September-2012, 2,366 men, aged 40-74 years and with >10 years life expectancy, were initially screened with PSA/digital rectal examination (DRE). Men with previous Bx or with recent urine infections were excluded. Men with abnormal DRE and/or PSA >3 ng/ml were submitted for PCA3. All men with PCA3 ≥ 35 underwent an initial biopsy (IBx) -12cores-. Men with PCA3 < 35 were randomized 1:1 to either IBx or observation. Re-biopsy(16-18 cores) criteria were PSA increase >.5 ng/ml at 4-6 months or PSAv > .75 ng/ml/year.

RESULTS

With median follow-up (FU) of 10.1 months, PCA3 was performed in 321/2366 men (13.57%), 289 at first visit and 32 during FU. All 110 PCA3+ men (34.3%) were biopsied and PCa was identified in 43 men in IBx (39.1%). In the randomized arm, 110 were observed and 101 underwent biopsy, finding 12 PCa (11.9%), showing a statistically significant reduction of PCa detection rate in this cohort (P<.001). Global PCa detection rates were 40.9% and 9.5% for the PCA3+ and PCA3- branches, respectively (P<.001). Area under the curve for PSA and PCA3 were .601 and .74, respectively. This is an ongoing prospective study limited by its short follow-up period and still limited enrolment.

CONCLUSIONS

PCA3 as a second line biomarker within an opportunistic dual screening protocol, can potentially avoid 65.7% and 50.1% biopsies at first round and at median FU of 10.1 months, respectively, just missing around 3.2% of high grade PCa.

Left lobe of the prostate during clinical prostate cancer screening: the dark side of the gland for right-handed examiners

BACKGROUND

The predictive value of the abnormality side during digital rectal examination (DRE) has never been studied, suggesting that physicians examined the left lobe of the gland as well as the right lobe. We aimed to assess the predictive value of the side of DRE abnormality for prostate cancer (PCa) detection and aggressiveness in right-handed urologists.

METHODS

An analysis of a prospective database was carried out that included all consecutive men undergoing prostate biopsies between 2001 and 2012. The main end point was the predictive value of the abnormality side during DRE for cancer detection in clinically suspicious unilateral T2 disease. The diagnostic performance of left- versus right-sided abnormality was also assessed in terms of sensitivity, specificity and negative/positive predictive values.

RESULTS

Overall, 308 patients had a suspicious unilateral clinical disease (detection rate 57.5%). The cancer detection rate was significantly higher in case of left-sided compared with right-sided clinical T2 stage (odds ratio 2.1). In case of left-sided disease, the number of positive cores, the rate of perineural invasion, the rate of primary grade 4 pattern and the percentage of cancer involvement per core were significantly higher compared with those reported for right-sided disease. The predictive value of abnormality laterality for cancer detection and aggressiveness remained statistically independent in multivariate models. The positive predictive value for cancer detection was 64.6 in case of suspicious left-sided disease versus 46.9 in case of right-sided disease.

CONCLUSIONS

The risks of detecting PCa and aggressive disease on biopsy are significantly higher when DRE reveals a suspicious left-sided clinical disease as compared with right-sided disease. Right-handed physicians should be aware of this variance in diagnostic performance and potential underdetection of left-sided clinical disease, and should improve their examination of the left lobe of the gland by conducting longer exams or changing the patient's position.

Alterations in mechanical properties are associated with prostate cancer progression

Cancer progression and metastasis have been shown to be accompanied by alterations in the mechanical properties of tissues, but the relationship between the mechanical properties and malignant behavior in prostate cancer (Pca) is less clear. The aims of this study were to detect the mechanical properties of benign prostatic hyperplasia (BPH) and Pca tissues on both the macro- and micro-scales, to explore the relationships between mechanical properties and malignant behavior and, finally, to identify the important molecules in the mechanotransduction signaling pathway. We demonstrated that the strain index of Pca tissue was significantly higher than that of BPH tissue on the macro-scale but the Young's modulus of the Pca tissues, especially in advanced Pca, was lower than that of BPH tissues on the micro-scale. These two seemingly contradictory results can be explained by the excessive proliferation of tumor cells (Ki-67) and the degradation of scaffold proteins (collagens). These data indicate that alterations of the macro- and micro-mechanical properties of Pca tissues with malignant behavior are contradictory. The mechanical properties of tissues might be useful as a new risk factor for malignancy and metastasis in Pca. Furthermore, collagens, matrix metalloproteinase, fibronectin, and integrins might be the important molecules in the mechanotransduction signaling pathway.

Clinico-pathological Correlation of Digital Rectal Examination Findings Amongst Nigerian Men with Prostatic Diseases: A Prospective Study of 236 Cases

Aims and Objective:

This study aims at correlating different digital rectal examination (DRE) abnormalities with histopathological results in patients with prostatic diseases.

Materials and Methods:

A prospective study of 236 patients who underwent prostate needle biopsy (PNB). Inclusion criteria were presence of abnormal DRE findings or elevated prostate specific antigen above 4 ng/ml or both. They all had 10-core extended transrectal biopsy and specimens were sent for histopathological examination. Correlations were made between DRE findings and histopathology results. Two separate multivariate logistic regression models were created; the first evaluated the relationship of predictors (DRE findings) to the likelihood of detecting cancer and the second explored predictors of high-grade cancer on PNB.

Results:

Two hundred and thirty-six patients were enrolled with a mean age of 66.9 years and range of 43-90 years. Histopathology results were malignant in 102 (43.2%) and benign in 134 (56.8%). Ninety-one (38.6%) and 145 (61.4%) had normal DRE and abnormal DRE findings with cancer detection rates of 23.1% and 55.8% respectively. Nodular prostate is the most common abnormality in 63.4% patients with abnormal DRE. Each sign of DRE had different predictive value with enhanced positive predictive value when combinations of abnormalities are present. Abnormal DRE is an independent predictor of high-grade tumor. Mean Gleason scores were 4.7 and 7.1 in patients with normal and abnormal DRE respectively.

Conclusion:

DRE is a useful and important tool in assessing patients with suspected prostate diseases who need prostate biopsy. An abnormal DRE correlated well with prostate cancer and independently predicted high-grade disease in these men.

Robotic mechanical localization of prostate cancer correlates with magnetic resonance imaging scans

PURPOSE

To evaluate the concordance of cancer location of the tissue mapping from a mechanical pressure transducer with magnetic resonance imaging (MRI) scans.

MATERIALS AND METHODS

A total of 60 indentations were performed on 5 prostate specimens obtained after radical prostatectomy utilizing a robotic indentation system. The mechanical elastic moduli of suspected malignant lesions were calculated and mapped, and their locations were compared with suspicious areas of malignancy on MRI scans.

RESULTS

The concordance rate between the location mapping from the robotic indentation system and MRI scans results was 90.0% (54/60). The sensitivity and specificity of the robotic indentation system were 87.9% (29/33) and 92.6% (25/27), respectively. The positive predictive value and negative predictive value were 93.5% (29/31) and 93.1% (27/29), respectively.

CONCLUSION

The locations of malignant lesions derived from our robotic indentation system correlated strongly with the locations of suspected areas of malignancy on MRI scans. Our robotic system may provide a more targeted biopsy of the prostate than conventional non-targeted systemic biopsy, possibly improving the diagnostic accuracy of prostatic biopsies for cancer.

Predictive value of digital rectal examination for prostate cancer detection is modified by obesity

The American Cancer Society's updated screening guidelines for prostate cancer (CaP) render digital rectal examination (DRE) optional. We investigated the impact of DRE on CaP detection among obese men. Data from 2794 men undergoing initial prostate biopsy at three centers were analyzed to assess CaP risk attributed to abnormal DRE across body mass index (BMI) categories. Predictive accuracies of a combination of PSA, age, race, center and biopsy year including or excluding DRE findings were compared by areas under the receiver-operating characteristics curves. In all cohorts, obese men were less likely to have abnormal DREs diagnosed than non-obese men. As BMI category increased, abnormal DREs became stronger predictors for overall CaP in individual (P-trends ≤ 0.05) and combined (P-trend<0.001) cohorts, and for high-grade CaP in the Italian (P-trend=0.03) and combined (P-trend=0.03) cohorts. DRE inclusion improved the predictive accuracy for overall and high-grade CaP detection among all obese men (P ≤ 0.032) but not normal-weight men (P ≥ 0.198). DRE inclusion also near-significantly improved overall CaP detection in obese men with PSA<4 ng ml(-1) (P=0.081). In conclusion, the predictive value of DRE is dependent on obesity and is significantly higher among obese men than normal-weight men.

Robotic palpation-based mechanical property mapping for diagnosis of prostate cancer

PURPOSE

The aim of this study was to estimate the mechanical properties (elasticity) of normal and cancer prostate tissues and to develop a tissue elasticity map for the diagnosis and localization of prostate cancer.

MATERIALS AND METHODS

A total of 735 sites from 35 radical prostatectomy specimens were used in the experiments using a robotic palpation system, and the elasticities of the specimens were estimated by a tissue characterization algorithm. The estimated elasticities from 21 regions were separated into normal and cancer tissues using the pathological information, and a tissue elasticity map was developed using numerical functions and a nonlinear surface-fitting method.

RESULTS

The mean elastic moduli of the normal and cancer tissues were 15.25 ± 5.88 and 28.80 ± 11.20 kPa, respectively. The base region had the highest elasticity, followed by the medial and apex regions. These results demonstrated the ability to separate the cancer tissue from the normal tissue based on its elastic modulus. The tissue elasticity mapping was carried out using the estimated elasticity and nonlinear surface fitting. The proposed map showed the elasticity and was used to estimate the elastic modulus of the prostate at any given region.

CONCLUSION

Tissue elasticity may be an important indicator of prostate cancer because the pathologic changes alter the tissue properties, including cell integrity and intercellular matrix. This work provides quantitative and objective information for the diagnosis of prostate cancer. In addition, these results may have implications for the localization of prostate cancers.

The implementation of screening for prostate cancer

The objective of this study was to determine whether screening for prostate cancer (PC) reduces PC mortality and, if so, whether the required criteria to be introduced as a population-based screening program are satisfied. A literature review was conducted through electronic scientific databases. The screening tests, that is, PSA and digital rectal examination, have limited sensitivity and specificity for detecting PC; screening produces a beneficial stage shift and reduces PC mortality. Nevertheless, PC screening causes a large increase in the cumulative incidence, and the understanding of the economic cost and quality-of-life parameters are limited. PC screening cannot be justified yet in the context of a public health policy.

The Use and Misuse of the PSA Test: A Retrospective Case Note Review of Testing in a UK Teaching Hospital

Introduction:

PSA testing is commonly performed by non-urological specialties in the hospital setting. The indications for requesting a PSA test can vary widely in this group and may not always be appropriate. This may generate unnecessary patient anxiety and additional testing. This study was designed to assess the appropriateness of PSA requests by non-urologists in the hospital setting.

Methods:

A computer search for patient details of all PSA requests within a 3 month period by non-urologists was generated by the pathology department. 130 consecutive case notes were then reviewed of which 95 met the inclusion criteria. The reason for each request was then determined to be appropriate or inappropriate according to standard urological practice.

Results:

95 patients were included. Of these, 61 (64%) requests were made by medical specialties, 17 (18%) were requested by orthopaedics, 12 (13%) by general surgery and the remaining 5 (5%) by other specialties. There were 26 (27%) requests deemed appropriate and 69 (73%) inappropriate. Of the inappropriate requests in 52 cases no reason was given, 14 were made immediately after acute urinary retention and 9 were during a suspected urinary infection. A rectal examination was performed in conjunction with the test in 24 cases.

Conclusion:

In this setting the majority of PSA requests made by non-urologists was inappropriate. This may be due to a lack of knowledge of the indication for PSA testing and the factors which may cause a false positive result. There was a low level of rectal examination. More education is needed to improve this situation.

Mechanical property characterization of prostate cancer using a minimally motorized indenter in an ex vivo indentation experiment

OBJECTIVES

To measure the mechanical property of prostatic tissues using a minimally motorized indenter and to determine whether measurable differences in mechanical property exist between cancerous and noncancerous tissues in an ex vivo experiment.

METHODS

A total of 552 sites from 46 prostate specimens taken during radical prostatectomy underwent an indentation experiment with a minimally motorized indenter, and the elastic modulus (Young's modulus) of the tissue was estimated.

RESULTS

The mean elastic modulus of the regions containing cancer and noncancer was 24.1 ± 14.5 and 17.0 ± 9.0 kPa, respectively. In the noncancerous regions, the prostate was separated into 5 parts according to the post hoc test for comparing the elastic modulus between the 2 groups: part 1, lateral apex; part 2, medial apex; part 3, lateral-mid; part 4, lateral base; and part 5, medial-mid and medial base. In the regions containing cancer tissue, the prostate was also separated into 5 parts: part 1, lateral apex and medial apex; part 2, lateral-mid; part 3, lateral base; part 4, medial base; and part 5, medial-mid. The elastic modulus was greater in the tissue with a Gleason score of 8 than in the other tissue. The elastic modulus was significantly greater in the tissue with a tumor volume >5 cm(3) than in the other tissue.

CONCLUSIONS

We determined the elastic moduli of prostatic tissue as a quantitative and objective parameter according to the regions of the prostate, the presence of cancerous tissue, the tumor volume, and the Gleason score.

Diagnostic value of finger-guided prostate nodule biopsy combined with systemic random biopsy

BACKGROUND/PURPOSE

The purpose of this study was to compare prostate cancer detection rates and pathology results, using the Gleason grading system, of 12-core systemic random transrectal ultrasound-guided prostate biopsy (SB) and 3-core finger-guided prostate nodule biopsy (FGNB).

METHODS

Between January 2002 and December 2006, 148 patients with digitally palpable prostate nodules received SB and additional FGNB. The prostate cancer detection rates and Gleason scores of positive cancer specimens were compared between SB and combination biopsy (SB + FGNB). The patients' characteristics, including age, prostate specific antigen (PSA), percentage of free PSA and prostate volume were also recorded.

RESULTS

With simple SB, FGNB, and combination biopsy, the prostate cancer detection rates were 39.9%, 37.9%, and 44.6%, respectively. Of the 66 patients with prostate cancer, the Gleason sum was underestimated in three patients with simple SB only and in one patient with FGNB only. The false-negative rates for SB and FGNB were 10.6% and 15.2%, respectively.

CONCLUSION

In patients with a palpable prostate nodule, combination biopsy with systemic and nodule biopsy could avoid some misdiagnoses of prostate cancer and provide more accurate information for pathology grading.

Critical appraisal of prostate-specific antigen in prostate cancer screening: 20 years later

Prostate-specific antigen (PSA) is secreted by all types of prostate epithelial cells and has been used for 2 decades as a biologic marker for prostate cancer (PCa). Since the implementation of PSA screening in the United States, the detection of PCa has increased, accompanied by a decrease in the incidence of high-grade cancer and PCa-specific mortality rates. It has been suggested that these decreases have resulted from the enhanced detection of PCa while still curable. These data have been the impetus for early detection programs, which have recommended the initiation of screening as early as 40 years of age. Despite widespread use, PSA screening remains controversial, principally because of the lack of evidence from randomized controlled trials demonstrating a mortality benefit that could outweigh the concerns of the costs of overdiagnosis and overtreatment. Two ongoing, randomized controlled trials are examining whether screening reduces the risk of PCa-related mortality, and the results of these studies are expected soon. Although it has its limitations, PSA still remains the best-studied marker for the detection of PCa.

The interobserver variability of digital rectal examination in a large randomized trial for the screening of prostate cancer

BACKGROUND

To analyze to what extent the percentage of suspicious digital rectal examination (DRE) findings vary between examiners and to what extent the percentage of prostate cancers (PCs) detected in men with these suspicious findings varies between examiners.

METHODS

In the first screening round of the European Randomized study of Screening for PC (ERSPC) Rotterdam, 7,280 men underwent a PSA-determination and DRE of whom 2,102 underwent prostate biopsy (biopsy indication PSA > or = 4.0 ng/ml and/or suspicious DRE and/or TRUS). Descriptive statistics of DRE-outcome per PSA-range were used to determine the observer variability of six examiners. Because this analysis did not correct properly for other predictors of a suspicious DRE (PSA-level, biopsy indication, TRUS-outcome, prostate volume and age), a logistic regression analysis controlling for these explanatory variables was performed as well.

RESULTS

In 2,102 men biopsied, 443 PCs were detected (PPV = 21%). For all PSA levels the percentage suspicious DRE varied between examiners from 4% to 28% and percentage PC detected in men with a suspicious DRE varied from 18% to 36%. Logistic regression analysis showed that three of six examiners considered DRE significantly more often abnormal than others (ORs 3.48, 2.80, 2.47, P < 0.001). For all examiners the odds to have PC was statistically significantly higher in case of a suspicious DRE (ORs 2.21-5.96, P < 0.05). This increased chance to find PC was not significantly observer-dependent.

CONCLUSIONS

Three of six examiners considered DRE significantly more often suspicious than the others. However, under equal circumstances a suspicious DRE executed by each examiner increased the chance of the presence of PC similarly.

The role of the digital rectal examination in subsequent screening visits in the European randomized study of screening for prostate cancer (ERSPC), Rotterdam

BACKGROUND

The value of digital rectal examination (DRE) as a screening test for prostate cancer (PC) is controversial in the current prostate-specific antigen (PSA) era.

OBJECTIVES

To determine (1) the additional value of a suspicious DRE for the detection of PC in men with an elevated PSA level in subsequent screenings and (2) the tumour characteristics of PCs detected in men with a suspicious DRE.

DESIGN, SETTING, PARTICIPANTS

Within the screening study, from 1997-2006 men aged 55-75 years were invited for an every 4-yr PSA determination. A PSA level > or =3.0ng/ml prompted a DRE and a transrectal ultrasound (TRUS)-guided, lateralized sextant biopsy. Throughout the three screenings of the ERSPC, Rotterdam, 5040 biopsy sessions were evaluated.

MEASUREMENTS

We determined the positive predictive values (PPVs) of a suspicious DRE and normal DRE, which entailed, respectively, the proportion of PCs detected in men with a suspicious DRE or normal DRE divided by, respectively, all biopsied men with a suspicious DRE or normal DRE.

RESULTS AND LIMITATIONS

At initial screening, the PPV of a suspicious DRE, in conjunction with an elevated PSA level, to detect PC was 48.6% compared to 22.4% for men with a normal DRE. Both PPVs decreased in consecutive screens: respectively, 29.9% versus 17.1% (screen 2) and 21.2% versus 18.2% (screen 3). Respectively, 71.0% (p<0.001), 68.8% (p<0.001), and 85.7% (p=0.002) of all PCs with a Gleason score >7 were detected in men with a suspicious DRE at screens 1, 2, and 3. A limitation is that only biopsied men were evaluated.

CONCLUSIONS

At initial and subsequent screenings, the chance of having cancer at biopsy was higher in men with a suspicious DRE compared to men with a normal DRE (to a lesser extent in subsequent screenings), and the combination of a PSA level > or =3.0ng/ml with a suspicious DRE resulted in detecting significantly more PCs with Gleason score >7. DRE may be useful in more selective screening procedures to decrease unnecessary biopsies and overdiagnosis.

Digital rectal examination and the diagnosis of prostate cancer--a study based on 8 years and three screenings within the European Randomized Study of Screening for Prostate Cancer (ERSPC), Rotterdam

BACKGROUND

Evidence indicates that an abnormal digital rectal examination (DRE) is a risk factor for high-grade prostate cancer (PC).

OBJECTIVE

To determine whether men with an initially suspicious DRE, a prostate-specific antigen (PSA) level > or = 3.0 ng/ml, and a benign prostate biopsy are at higher risk for significant PC at rescreening than men with an initially normal DRE, and whether an adaptation of the rescreening interval is warranted for this group.

DESIGN, SETTING, AND PARTICIPANTS

Within the European Randomized Study of Screening for Prostate Cancer (ERSPC), Rotterdam, 2218 men underwent biopsy of the prostate (from 1993 to 2000) with a benign result at initial screening. The serum PSA was determined every 4 yr. A PSA level of > or = 3.0 ng/ml prompted a DRE and a lateralised sextant biopsy.

MEASUREMENTS

Number and characteristics of PCs found at repeat screenings and as interval cancers (ICs) were compared between men with or without a suspicious DRE result at initial screening. Multivariate logistic regression analyses were performed to evaluate if an initially suspicious DRE was a significant predictor for detecting cancer at consecutive screenings.

RESULTS AND LIMITATIONS

After 4 yr, the total number of PCs detected in men with and without an initially suspicious DRE was, respectively, 27 (6%) versus 103 (6%) (p=0.99). After 8 yr these numbers increased, respectively, to 45 (10%) versus 167 (10%) (p=0.88). The proportion of clinically significant PCs was 2% and 3%, respectively, for the group with initially normal and abnormal DRE after 8 yr. Having a suspicious DRE result at initial screening was not a significant predictor for detecting PC after 4 yr [odds ratio (OR)=1.15, p=0.59) or 8 yr (OR=1.41, p=0.43)]. A limitation of this study is the relatively short follow-up of 8 yr.

CONCLUSIONS

During a follow-up of 8 yr after initial cancer-negative biopsy, an initially suspicious DRE did not influence the chance for detection of cancer or significant cancer at later screens. An adaptation of the rescreening interval on the basis of the initial DRE-outcome is not warranted in future population-based screening for prostate cancer.