When to biopsy and when to stop biopsying

Metabolic analysis using HR-MAS in prostate tissue for prostate cancer diagnosis

INTRODUCTION

In this study we used nuclear magnetic resonance spectroscopy in prostate tissue to provide new data on potential biomarkers of prostate cancer in patients eligible for prostate biopsy.

MATERIAL AND METHODS

Core needle prostate tissue samples were obtained. After acquiring all the spectra using a Bruker Avance III DRX 600 spectrometer, tissue samples were subjected to routine histology to confirm presence or absence of prostate cancer. Univariate and multivariate analyses with metabolic and clinical variables were performed to predict the occurrence of prostate cancer.

RESULTS

A total of 201 patients, were included in the study. Of all cores subjected to high-resolution magic angle spinning (HR-MAS) followed by standard histological study, 56 (27.8%) tested positive for carcinoma. According to HR-MAS probe analysis, metabolic pathways such as glycolysis, the Krebs cycle, and the metabolism of different amino acids were associated with presence of prostate cancer. Metabolites detected in tissue such as citrate or glycerol-3-phosphocholine, together with prostate volume and suspicious rectal examination, formed a predictive model for prostate cancer in tissue with an area under the curve of 0.87, a specificity of 94%, a positive predictive value of 80% and a negative predictive value of 84%.

CONCLUSIONS

Metabolomics using HR-MAS analysis can uncover a specific metabolic fingerprint of prostate cancer in prostate tissue, using a tissue core obtained by transrectal biopsy. This specific fingerprint is based on levels of citrate, glycerol-3-phosphocholine, glycine, carnitine, and 0-phosphocholine. Several clinical variables, such as suspicious digital rectal examination and prostate volume, combined with these metabolites, form a predictive model to diagnose prostate cancer that has shown encouraging results.

Discrepancies in Gleason score between needle core biopsy and radical prostatectomy specimens with correlation between clinical and pathological staging

BACKGROUND

The studies have shown that GS given after assessment of the entire prostate gland on the radical prostatectomy specimen may differ from GS given after examination of a small sample from needle core biopsy. We conducted this study to assess discrepancies in the Gleason score between NCB and RP specimens and to find out the correlation between the clinical stage and pathological stage.

METHODS

The study included 174 patients with carcinoma prostate which underwent robotic-assisted radical prostatectomy (RARP). Pre-operative Gleason score was determined on 12-core biopsy samples under trans-rectal ultrasound (TRUS) guidance. The Gleason score obtained from the radical prostatectomy specimen was compared with that of the NCB Gleason score to find out differences.

RESULTS

The preoperative Gleason score (GS) ranges from 6 to 9 with a mean GS of 6.97 ± 1.02. The post-operative GS ranges between 6 and 10 with mean and GS of 7.5 ± 1.10. On the pre-operative assessment of biopsy specimens, 70 (43.2%) patients had a GS of 6, while 44 patients had a GS of 7 (27.1%) and 48 (29.8%) patients had a GS of more than 7. On the postoperative assessment of specimens, 31 (19.1%) patients had post-operative GS of 6, while 66 (41%) patients had GS of 7 and 74 (41.1%) patients had GS of more than 7. When pre-operative GS and post-operative GS were compared, no changes were observed in the GS of 79 patients, whereas 83 patients showed the difference in GS, with 75 patients showing up-gradation and eight patients marked as down-graded.

CONCLUSION

concordance between biopsy and the pathology results directly affects the prognosis of the patient. The results of our study demonstrated the rate of discordance between Gleason scores obtained from transrectal prostate biopsy and RP surgical specimens. This rate brings into question the accuracy of the chosen treatment.

Risk of Upgrading from Prostate Biopsy to Radical Prostatectomy Pathology-Does Saturation Biopsy of Index Lesion during Multiparametric Magnetic Resonance Imaging-Transrectal Ultrasound Fusion Biopsy Help?

PURPOSE

We sought to determine whether saturation of the index lesion during magnetic resonance imaging-transrectal ultrasound fusion guided biopsy would decrease the rate of pathological upgrading from biopsy to radical prostatectomy.

MATERIALS AND METHODS

We analyzed a prospectively maintained, single institution database for patients who underwent fusion and systematic biopsy followed by radical prostatectomy in 2010 to 2016. Index lesion was defined as the lesion with largest diameter on T2-weighted magnetic resonance imaging. In patients with a saturated index lesion transrectal fusion biopsy targets were obtained at 6 mm intervals along the long axis of the index lesion. In patients with a nonsaturated index lesion only 1 target was obtained from the lesion. Gleason 6, 7 and 8-10 were defined as low, intermediate and high risk, respectively.

RESULTS

Included in the study were 208 consecutive patients, including 86 with a saturated and 122 with a nonsaturated lesion. Median patient age was 62.0 years (IQR 10.0) and median prostate specific antigen was 7.1 ng/ml (IQR 8.0). The median number of biopsy cores per index lesion was higher in the saturated lesion group (4 vs 2, p <0.001). The risk category upgrade rate from systematic only, fusion only, and combined fusion and systematic biopsy results to prostatectomy was 40.9%, 23.6% and 13.8%, respectively. The risk category upgrade from combined fusion and systematic biopsy results was lower in the saturated than in the nonsaturated lesion group (7% vs 18%, p = 0.021). There was no difference in the upgrade rate based on systematic biopsy between the 2 groups. However, fusion biopsy results were significantly less upgraded in the saturated lesion group (Gleason upgrade 20.9% vs 36.9%, p = 0.014 and risk category upgrade 14% vs 30.3%, p = 0.006).

CONCLUSIONS

Our results demonstrate that saturation of the index lesion significantly decreases the risk of upgrading on radical prostatectomy by minimizing the impact of tumor heterogeneity.

Prostate Cancer Predictive Simulation Modelling, Assessing the Risk Technique (PCP-SMART): Introduction and Initial Clinical Efficacy Evaluation Data Presentation of a Simple Novel Mathematical Simulation Modelling Method, Devised to Predict the Outcome of Prostate Biopsy on an Individual Basis

INTRODUCTION

We developed a mathematical "prostate cancer (PCa) conditions simulating" predictive model (PCP-SMART), from which we derived a novel PCa predictor (prostate cancer risk determinator [PCRD] index) and a PCa risk equation. We used these to estimate the probability of finding PCa on prostate biopsy, on an individual basis.

MATERIALS AND METHODS

A total of 371 men who had undergone transrectal ultrasound-guided prostate biopsy were enrolled in the present study. Given that PCa risk relates to the total prostate-specific antigen (tPSA) level, age, prostate volume, free PSA (fPSA), fPSA/tPSA ratio, and PSA density and that tPSA ≥ 50 ng/mL has a 98.5% positive predictive value for a PCa diagnosis, we hypothesized that correlating 2 variables composed of 3 ratios (1, tPSA/age; 2, tPSA/prostate volume; and 3, fPSA/tPSA; 1 variable including the patient's tPSA and the other, a tPSA value of 50 ng/mL) could operate as a PCa conditions imitating/simulating model. Linear regression analysis was used to derive the coefficient of determination (R²), termed the PCRD index. To estimate the PCRD index's predictive validity, we used the χ² test, multiple logistic regression analysis with PCa risk equation formation, calculation of test performance characteristics, and area under the receiver operating characteristic curve analysis using SPSS, version 22 (P < .05).

RESULTS

The biopsy findings were positive for PCa in 167 patients (45.1%) and negative in 164 (44.2%). The PCRD index was positively signed in 89.82% positive PCa cases and negative in 91.46% negative PCa cases (χ² test; P < .001; relative risk, 8.98). The sensitivity was 89.8%, specificity was 91.5%, positive predictive value was 91.5%, negative predictive value was 89.8%, positive likelihood ratio was 10.5, negative likelihood ratio was 0.11, and accuracy was 90.6%. Multiple logistic regression revealed the PCRD index as an independent PCa predictor, and the formulated risk equation was 91% accurate in predicting the probability of finding PCa. On the receiver operating characteristic analysis, the PCRD index (area under the curve, 0.926) significantly (P < .001) outperformed other, established PCa predictors.

CONCLUSION

The PCRD index effectively predicted the prostate biopsy outcome, correctly identifying 9 of 10 men who were eventually diagnosed with PCa and correctly ruling out PCa for 9 of 10 men who did not have PCa. Its predictive power significantly outperformed established PCa predictors, and the formulated risk equation accurately calculated the probability of finding cancer on biopsy, on an individual patient basis.

Analysis of Laterality and Percentage of Tumor Involvement in 1386 Prostatectomized Specimens for Selection of Unilateral Focal Cryotherapy

In total, 1386 paraffin embedded radical prostatectomy specimens from patients with clinically localized prostate cancer (PCa) excised between 2002–06 were analyzed. Pathologic assessment paid particular attention to laterality and percentage of tumor involvement (PTI) along with pathologic Gleason Score (pGS). Completely unilateral cancers were identified in 254 (18.3%) patients, and in 39% cases of them the signs of clinically significant PCa were revealed. The majority of unilateral tumors (72%) were low volume with a PTI of ≤5. This study suggests that only a select group of men diagnosed with PCa have completely unilateral cancers that would be amenable to focal ablation therapy targeting 1 lobe. Further study is needed to develop predictive models for those patients likely to have small, unilateral cancers that may be amenable to focal therapy.

[Prostate biopsy: Procedure in the clinical routine]

Over the last decade there has been a 25% decrease in the mortality rates for prostate cancer. The reasons for this significant decrease are most likely associated with the application of urological screening tests. The main tools for early detection are currently increased public awareness of the disease, prostate-specific antigen (PSA) tests and transrectal ultrasound (TRUS) guided topographically assignable biopsy sampling. Together with the histopathological results these features provide essential information for risk stratification, diagnostics and therapy decisions. The evolution of prostate biopsy techniques as well as the use of PSA testing has led to an increased identification of asymptomatic men, where further clarification is necessary. Significant efforts and increased clinical research focus on determining the appropriate indications for a prostate biopsy and the optimal technique to achieve better detection rates. The most widely used imaging modality for the prostate is TRUS; however, there are no clearly defined standards for the clinical approach for each individual biopsy procedure, dealing with continuous technical optimization and in particular the developments in imaging. In this review the current principles, techniques, new approaches and instrumentation of prostate biopsy imaging control are presented within the framework of the structured educational approach.

Prostate cancer: diagnostic performance of real-time shear-wave elastography

PURPOSE

To prospectively evaluate the performance of real-time ultrasonographic (US) shear-wave elastography (SWE) in the diagnosis of peripheral zone prostate cancer in patients with high and/or increasing prostate-specific antigen levels and/or abnormal digital rectal examination results.

MATERIALS AND METHODS

After signing an informed consent form, men referred for transrectal prostate biopsy were enrolled in this prospective HIPAA-compliant two-center study, which was conducted with institutional review board approval. Transrectal US SWE of the prostate was performed after a conventional transrectal US examination and immediately before US-guided 12-core sextant biopsy. For each sextant, the maximum SWE value was measured and matched to the pathologic results of that sextant biopsy. The diagnostic performance of SWE was assessed at both patient and sextant levels. The elasticity value maximizing the Youden index was used to derive sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

The elasticity values were matched to pathologic results for a total of 1040 peripheral zone sextants in 184 men. One hundred twenty-nine positive biopsy findings (size, ≥3 mm; Gleason score, ≥6) were identified in 68 patients. The sextant-level sensitivity, specificity, PPV, NPV, and area under the receiver operating characteristic curve for SWE with a cutoff of 35 kPa for differentiating benign from malignant lesions were 96% (95% confidence interval [CI]: 95%, 97%), 85% (95% CI: 83%, 87%), 48% (95% CI: 46%, 50%), 99% (95% CI: 98%, 100%), and 95% (95% CI: 93%, 97%), respectively.

CONCLUSION

Use of a 35-kPa threshold at SWE may provide additional information for the detection and biopsy guidance of prostate cancer, enabling a substantial reduction in the number of biopsies while ensuring that few peripheral zone adenocarcinomas are missed.

Imaging and intervention in prostate cancer: Current perspectives and future trends

Prostate cancer is the commonest malignancy in men that causes significant morbidity and mortality worldwide. Screening by digital rectal examination (DRE) and serum prostate-specific antigen (PSA) is used despite its limitations. Gray-scale transrectal ultrasound (TRUS), used to guide multiple random prostatic biopsies, misses up to 20% cancers and frequently underestimates the grade of malignancy. Increasing the number of biopsy cores marginally increases the yield. Evolving techniques of real-time ultrasound elastography (RTE) and contrast-enhanced ultrasound (CEUS) are being investigated to better detect and improve the yield by allowing “targeted” biopsies. Last decade has witnessed rapid developments in magnetic resonance imaging (MRI) for improved management of prostate cancer. In addition to the anatomical information, it is capable of providing functional information through diffusion-weighted imaging (DWI), magnetic resonance spectroscopy (MRS), and dynamic contrast-enhanced (DCE) MRI. Multi-parametric MRI has the potential to exclude a significant cancer in majority of cases. Inclusion of MRI before prostatic biopsy can reduce the invasiveness of the procedure by limiting the number of cores needed to make a diagnosis and support watchful waiting in others. It is made possible by targeted biopsies as opposed to random. With the availability of minimally invasive therapeutic modalities like high-intensity focused ultrasound (HIFU) and interstitial laser therapy, detecting early cancer is even more relevant today. [18F]--fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸FDG PET/CT) has no role in the initial evaluation of prostate cancer. Choline PET has been recently found to be more useful. Fluoride-PET has a higher sensitivity and resolution than a conventional radionuclide bone scan in detecting skeletal metastases.

Multiple repeat prostate biopsies and the detection of clinically insignificant cancer in men with large prostates

OBJECTIVE

To determine the impact of repeating prostate biopsies on the risk of detecting clinically insignificant prostate cancer (PCa) in larger prostate glands.

METHODS

We performed a retrospective cohort study using patients enrolled in our institutional PCa registry from 1991 to 2008 to assess the association of prostate volume and clinically insignificant PCa in men undergoing multiple prostate biopsies. Patients were stratified by prostate volume into 2 cohorts (<50 cm(3) or ≥50 cm(3)). Additionally, patients were stratified by prostate biopsy on which PCa was identified (1 biopsy or ≥3 biopsies).

RESULTS

Within the subgroup of patients with prostate volume ≥50 cm(3) requiring ≥3 biopsies before cancer diagnosis, 72.6% (45/62) had pathologic Gleason scores ≤6 and 81.6% (49/60) had an estimated tumor volume of ≤10% at the time of radical prostatectomy. This was significantly different from patients with prostate volume <50 cm(3) diagnosed on their first biopsy, in which only 48.5% (656/1349) were found to have Gleason scores ≤6 and 54.2% (705/1300) had estimated tumor volume ≤10% (P <.01). There was no significant difference in the rate of Gleason score upgrading at time of prostatectomy between any of the subgroups.

CONCLUSION

PCas detected in men with prostatic enlargement requiring multiple biopsies are more likely to be low-grade, low-volume tumors at final pathology than men without prostate enlargement. Men with larger prostates who have already had prior negative biopsies should be counseled regarding the increased risk of detecting clinically insignificant PCa with additional biopsies.

Ultrasound elastography of the prostate: state of the art

Prostate cancer is the cancer exhibiting the highest incidence rate and it appears as the second cause of cancer death in men, after lung cancer. Prostate cancer is difficult to detect, and the treatment efficacy remains limited despite the increase use of biological tests (prostate-specific antigen [PSA] dosage), the development of new imaging modalities, and the use of invasive procedures such as biopsy. Ultrasound elastography is a novel imaging technique capable of mapping tissue stiffness of the prostate. It is known that prostatic cancer tissue is often harder than healthy tissue (information used by digital rectal examination [DRE]). Two elastography techniques have been developed based on different principles: first, quasi-static (or strain) technique, and second, shear wave technique. The tissue stiffness information provided by US elastography should improve the detection of prostate cancer and provide guidance for biopsy. Prostate elastography provides high sensitivity for detecting prostate cancer and shows high negative predictive values, ensuring that few cancers will be missed. US elastography should become an additional method of imaging the prostate, complementing the conventional transrectal ultrasound and MRI. This technique requires significant training (especially for quasi-static elastography) to become familiar with acquisition process, acquisition technique, characteristics and limitations, and to achieve correct diagnoses.

Is an initial saturation prostate biopsy scheme better than an extended scheme for detection of prostate cancer? A systematic review and meta-analysis

CONTEXT

The optimal initial prostate biopsy core number is still an issue with many unanswered questions and significant controversy.

OBJECTIVE

To compare diagnostic values of initial saturation prostate biopsy scheme and extended scheme with respect to prostate-specific antigen (PSA) levels, prostate volume (PV), and PSA density (PSAD).

EVIDENCE ACQUISITION

Electronic databases including Medline, Web of Knowledge, and the Cochrane Library were searched through November 1, 2012. Experts were consulted, and references from relevant articles were scanned. The meta-analysis was conducted with RevMan 5.1, according to the PRISMA guidelines. Mantel-Haenszel estimates were calculated and pooled under a fixed or random effect model, with data expressed as risk difference (RD) and 95% confidence interval (CI).

EVIDENCE SYNTHESIS

We analyzed eight trials with a total of 11997 participants who underwent transrectal ultrasound guided prostate biopsies for the first time and met inclusion criteria. Studies consisted of one paired design study, two randomized clinical trials, and five nonrandomized studies. Saturation biopsy scheme showed a significant advantage in prostate cancer (PCa) detection over an extended scheme (RD: 0.04; 95% CI, 0.01-0.08; p=0.02). In addition, subgroup analyses found a saturation protocol to be superior to an extended protocol in the detection of PCa in men with PSA <10 ng/ml (RD: 0.04; 95% CI, 0.01-0.07; p=0.002), PV >40 ml (RD: 0.05; 95%CI, 0.01-0.09; p=0.02), or PSAD <0.25 ng/ml per gram (RD: 0.04; 95% CI, 0.00-0.09; p=0.04).

CONCLUSIONS

The existing evidence indicates that an initial saturation biopsy scheme is more efficient than an extended scheme for PCa detection, especially for those men with lower PSA levels, higher PV, or lower PSAD, without increasing complications and the amount of insignificant cancer.

Contemporary pathologic characteristics and oncologic outcomes of prostate cancers missed by 6- and 12-core biopsy and diagnosed with a 21-core biopsy protocol

PURPOSE

To assess the pathological and the oncologic outcomes of the prostate cancer (PCa) missed by 6- and 12-core biopsy protocols by using a reference 21-core scheme.

MATERIALS AND METHODS

Between 2001 and 2009, all patients who had PCa detected in an initial 21-core TRUS biopsy scheme and were treated by a radical prostatectomy (RP) were included. Patients were sorted in 3 groups according to the diagnosis site: sextant (6 first cores; group 1), peripheral zone (12 first cores; group 2) or midline/transitional zone (after 21 cores; group 3). Demographics, pathological features in biopsy and RP specimens and follow-up after RP were analyzed. The 5-year progression-free survival (PFS) was studied in the 3 groups.

RESULTS

During the study period, 443 patients were included. Among them, 67, 23.7 and 9.2% were, respectively, diagnosed in groups 1, 2 and 3. Among PCa diagnosed in midline/transition zone cores, 42% were intermediate or high risk. Unfavorable disease was more frequently reported in group 1 in terms of extraprostatic extension (P = 0.001), high Gleason score (P = 0.001) and progression (P = 0.001). No significant difference was observed between groups 2 and 3 in terms of pathological features in RP specimens and oncologic outcome. The 5-year PFS was 89.7% and not significantly different in patients diagnosed with a 12-core scheme compared to those diagnosed only with 21-core scheme (P = 0.332).

CONCLUSIONS

Our findings emphasize that PCa diagnosed only in a 21-core protocol is at least as aggressive as PCa detected in a 12-core scheme. This study invalidates the widespread idea sustaining that cancers diagnosed by more than 12 biopsies are less aggressive.

False-positive screening results in the Finnish prostate cancer screening trial

BACKGROUND

There is evidence that prostate cancer (PC) screening with prostate-specific antigen (PSA) serum test decreases PC mortality, but screening has adverse effects, such as a high false-positive (FP) rate. We investigated the proportion of FPs in a population-based randomised screening trial in Finland.

METHODS

Finland is the largest centre in the European Randomized Study of Screening for Prostate Cancer. We have completed three screening rounds with a 4-year screening interval (mean follow-up time 9.2 years) using a PSA cutoff level of 4.0 ng ml(-1); in addition, men with PSA 3.0-3.9 and a positive auxiliary test were referred. An FP result was defined as a positive screening result without cancer in biopsy within 1 year from the screening test.

RESULTS

The proportion of FP screening results varied from 3.3 to 12.1% per round. Of the screened men, 12.5% had at least one FP during three rounds. The risk of next-round PC following an FP result was 12.3-19.7 vs 1.4-3.7% following a screen-negative result (depending on the screening round), risk ratio 3.6-9.9. More than half of the men with one FP result had another one at a subsequent screen. Men with an FP result were 1.5 to 2.0 times more likely to not participate in subsequent rounds compared with men with a normal screening result (21.6-29.6 vs 14.0-16.7%).

CONCLUSION

An FP result is a common adverse effect of PC screening and affects at least every eighth man screened repeatedly, even when using a relatively high cutoff level. False-positive men constitute a special group that receives unnecessary interventions but may harbour missed cancers. New strategies are needed for risk stratification in PC screening to minimise the proportion of FP men.

Rational approach to implementation of prostate cancer antigen 3 into clinical care

BACKGROUND

Prostate cancer antigen 3 (PCA3) encodes a prostate-specific messenger ribonucleic acid (mRNA) that serves as the target for a novel urinary molecular assay for prostate cancer detection. The objective of the current study was to evaluate the ability of PCA3, added to measurements of serum prostate-specific antigen (PSA), to predict cancer detection by extended template biopsy.

METHODS

Between September 2006 and December 2007, whole urine samples were collected after attentive digital rectal examinations from 187 men before they underwent ultrasound-guided, 12-core prostate biopsy in a urology outpatient clinic. Urine PCA3/PSA mRNA ratio scores were measured within 1 month, and serum PSA was measured within 6 months prior to biopsy. Those measurements were related to cancer-positive biopsies.

RESULTS

Overall, 87 of 187 biopsies (46.5%) were positive for cancer. The sensitivity and specificity of a PCA3 score > or =35 for positive biopsy were 52.9% and 80%, respectively, and the positive and negative predictive values were 69.7% and 66.1%, respectively. By using receiver operating characteristic curve analysis, PSA alone resulted in an area under the curve (AUC) of 0.63 for prostate cancer detection; whereas a combined PSA and PCA3 score resulted in an AUC of 0.71. The likelihood of prostate cancer detection rose with increasing PCA3 score ranges (P > .0001), providing possible PCA3 score parameters for stratification into groups at low risk, moderate risk, high risk, and very high risk for a positive biopsy.

CONCLUSIONS

Adding PCA3 to serum PSA improved prostate cancer prediction. The use of PCA3 in a clinical setting may help to stratify patients according to their risk for biopsy and cancer detection, although a large-scale validation study will be needed to address assay standardization, optimal cutoff values, and appropriate patient populations.

Thirty-two-channel coil 3T magnetic resonance-guided biopsies of prostate tumor suspicious regions identified on multimodality 3T magnetic resonance imaging: technique and feasibility

OBJECTIVES

To test the technique and feasibility of translating tumor suspicious region maps in the prostate, obtained by multimodality, anatomic, and functional 3T magnetic resonance imaging (MRI) data to 32-channel coil, T2-weighted (T2-w), 3T MR images, for directing MR-guided biopsies. Furthermore, to evaluate the practicability of MR-guided biopsy on a 3T MR scanner using a 32-channel coil and a MR-compatible biopsy device.

MATERIALS AND METHODS

Twenty-one patients with a high prostate-specific antigen (>4.0 ng/mL) and at least 2 prior negative transrectal ultrasound-guided biopsies of the prostate underwent an endorectal coil 3T MRI, which included T2-w, diffusion weighted and dynamic contrast enhanced MRI. From these multimodality images, tumor suspicious regions (TSR) were determined. The 3D localization of these TSRs within the prostatic gland was translated to the T2-w MR images of a subsequent 32-channel coil 3T MRI. These were then biopsied under 3T MR guidance.

RESULTS

In all patients, TSRs could be identified and accurately translated to subsequent 3T MR images and biopsied under MR guidance. Median MR biopsy procedure time was 35 minutes. Of the 21 patients, 8 (38%) were diagnosed with prostate cancer, 6 (29%) had evidence of prostatitis, 6 (29%) had combined inflammatory and atrophic changes, and only 1 (5%) patient had no identifiable pathology.

CONCLUSIONS

Multimodality, 3T MRI determined TSRs could effectively be translated to T2-weighted images, to be used for MR biopsies. 3T MR-guided biopsy based on these translated TSRs was feasible, performed in a clinical useful time, and resulted in a high number of positive results.

Optimal Sampling Sites for Repeat Prostate Biopsy: A Recursive Partitioning Analysis of Three-Dimensional 26-Core Systematic Biopsy

OBJECTIVES

To explore an optimal combination of sampling sites to detect prostate cancer in a repeat biopsy setting.

METHODS

A transrectal ultrasound-guided systematic three-dimensional 26-core biopsy (3D26PBx), a combination of transrectal 12 and transperineal 14 core biopsies, was performed in 235 Japanese men with prior negative biopsy. Using recursive partitioning, we evaluated cancer detection of all possible combinations of sampling sites and selected the combination that provides the highest cancer detection rate at a given number of biopsy cores.

RESULTS

Prostate cancer was detected in 87 of the 235 (37%) men. The 3D26PBx improved cancer detection by 89% relative to the conventional transrectal sextant biopsy. Neither Gleason score nor percentage of Gleason 4/5 cancers differed between cancers with and without positive cores within the transrectal sextant-sampling sites. A three-dimensional combination of transrectal and transperineal approaches outperformed either transrectal or transperineal approach alone. Recursive partitioning revealed that a three-dimensional 16-core (transrectal eight cores plus transperineal eight cores) biopsy could detect all the cancers with the minimum number of cores.

CONCLUSIONS

We propose a three-dimensional combination of transrectal eight cores taken from the far lateral peripheral zone and the parasagittal base, and transperineal eight cores taken from the anterior and posterior apex and the transition zone as an optimal set of sampling sites for repeat biopsy.

Imaging of prostate cancer

The role of imaging in the diagnosis and management of prostate is reviewed. Transrectal ultrasonography, which can be used to guide biopsy, is most frequently used imaging technique in cancer detection. For determining the extent of disease, CT and MR imaging are the most commonly used modalities; bone scintigraphy and positron emission tomography have roles only in advanced disease. Currently, the role of imaging in prostate cancer is evolving to improve disease detection and staging, to determine the aggressiveness of disease, and to predict outcomes in different patient populations

Prostatastanzbiopsie unter Diclofenac

BACKGROUND

The aim of this study was to evaluate the efficacy of diclofenac to reduce pain during prostate biopsy.

METHODS

After prospective randomization all patients received an intrarectal lidocaine gel instillation. Group 1 (n=80) functioned as control group, group 2 (n=72) received a placebo, and group 3 (n=76) a 50 mg diclofenac suppository in addition. Patients were asked to identify their pain score (VAS 10) after the biopsy. Two weeks later, the patients were called and asked about the post-biopsy course.

RESULTS

Patients in the diclofenac group had significantly lower pain scores than control or placebo group patients. Another biopsy without additional anesthesia was refused by 25% of the control group and 34% of the placebo group, but only by 11% of the diclofenac group (p<0.05).

CONCLUSIONS

The preinterventional administration of diclofenac suppositories is a simple but efficient procedure for pain reduction in patients who undergo prostate biopsy.

Surgical management of prostate cancer: Advances based on a rational approach to the data

The management of localised prostate cancer has undergone important changes in the past two decades, with major improvements in surgical technique, a greater emphasis on structured assessment of quality of life, and a greater attempt to tailor treatment to biological risk. Disease diagnosis is predicated on identification of demographic risk factors, serum levels of prostate-specific antigen and its derivatives, and extended biopsy techniques. Surgical removal of the prostate may be accomplished by open or minimally invasive techniques and in experienced hands results in good functional outcomes a high rate of cure for those with organ confined disease. Radical prostatectomy is also appropriate in selected patients with locally advanced disease and after failed radiation therapy.

Does prior benign prostate biopsy predict outcome for patients treated with radical perineal prostatectomy?

OBJECTIVES

To determine the effect of prior benign prostate biopsies on the surgical and clinical outcomes of patients treated with radical perineal prostatectomy for prostate cancer.

METHODS

A total of 1369 patients with clinically localized prostate cancer underwent radical prostatectomy by a single surgeon between 1991 and 2001. A subset of 203 patients (14.9%), who had undergone at least one prior benign prostate biopsy for a rising prostate-specific antigen and/or abnormal digital rectal examination, constituted our study population. A total of 1115 patients with no prior biopsy represented our control group. After prostatectomy, patients were evaluated at 6-month intervals for biochemical evidence of recurrence, defined as a prostate-specific antigen level of 0.5 ng/mL or greater.

RESULTS

Patients with a prior benign biopsy had more favorable pathologic features with more organ-confined (74% versus 64%; P <0.001) and less margin-positive (9.8% versus 18%) disease. Only 24 patients (12%) in the study group (versus 20% in control group; P = 0.01) had eventual evidence of biochemical failure. Kaplan-Meier analyses suggested that patients with prior benign biopsies have improved biochemical disease-free survival, especially for those with more aggressive disease (Gleason sum 7 or greater; P <0.01). Overall, patients in the study group had lower probability (odds ratio 0.57, P <0.001) of biochemical failure compared with those in the control group.

CONCLUSIONS

A prior benign prostate biopsy may be independently associated with more favorable surgical and biochemical outcomes after prostatectomy. Additional studies are needed to confirm these findings.

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.

Prostate cancer detection and tumor characteristics in men with multiple biopsy sessions

PURPOSES

To address prostate cancer (PCa) detection with respect to the number of biopsy sessions performed, to identify risk factors for detection after a negative biopsy, and to analyze the clinical characteristics of the detected tumors.

SCOPE

Only biopsied men (sextant) were included. A total of 1011 biopsy sessions were carried out in 770 men; 172 underwent a second prostate biopsy and 51 a third biopsy. During the first biopsy round, 111 cancers were found (14.4%), 27 in the second (15.7%), and five during the third round (9.8%), P=0.156. Only high-grade PIN or atypia were identified as independent predictors or PCa detection in subsequent biopsies (P=0.008). A nonsignificant increase of clinically localized tumors, and a decrease of metastatic and poorly differentiated cases were found when more biopsy sessions were needed for detection.

CONCLUSIONS

A nonsignificant trend to lower cancer detection rates and less clinical relevance of the tumors detected can be observed when more biopsy rounds are needed for detection.