Sensitivity and specificity of sextant biopsies in the detection of prostate cancer: preliminary report

Contribution of canine olfaction in the diagnostic strategy of intermediate and high-risk prostate cancer: a double-blind validation study

PURPOSE

Prostate cancer diagnosis is confirmed with a prostate biopsy, which is invasive and unpleasant. Adding canine olfaction into the diagnostic protocol could help avoid unnecessary biopsies. This study aims to determine whether dogs can identify ISUP (International Society of Urological Pathology) > 2 prostate cancer.

MATERIALS AND METHODS

This double-blind, prospective, validation study included men with suspected prostate cancer between November 2022 and April 2023 in France. They were classified into two groups according to their prostate biopsy results; cases (ISUP > 2) and controls (ISUP < 1 or negative). Seven dogs analyzed their urine. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for canine olfactory detection of ISUP ≥ 2 prostate cancer were measured and compared with that of prostate MRI versus prostate biopsy.

RESULTS

The seven dogs analyzed 151 urine samples, 78 from the case group and 73 from the control group. The minimal and maximal observed values were 54% and 86% for sensitivity, and 69% and 88% for specificity. Five dogs had a sensitivity above 73% and six dogs had a specificity above 75%. The kappa coefficient quantifying agreement between the biopsy result and the MRI PI-RADS ≥ 3 was 0.17 [- 0.14; 0.17], 0.20 [0.02-0.33] for PI-RADS ≥ 4 and 0.64 [0.5-0.75] for canine olfaction meaning there is a substantial agreement between the biopsy result and canine olfaction.

CONCLUSIONS

Based on this study, the non-invasive and safe canine olfaction technique seems reliable for diagnosing ISUP ≥ 2 prostate cancer. Combined with prostate MRI, it may improve the decision-making process when choosing to perform prostate biopsies.

Preliminary Evaluation of Hydraulic Needle Delivery System for Magnetic Resonance Imaging-Guided Prostate Biopsy Procedures

In clinical routine, the prostate biopsy procedure is performed with the guidance of transrectal ultrasound (TRUS) imaging to diagnose prostate cancer. However, the TRUS-guided prostate biopsy brings reliability concerns due to the lack of contrast difference between prostate tissue and lesions. In this study, a novel hydraulic needle delivery system that is designed for performing magnetic resonance imaging (MRI)-guided prostate biopsy procedure with transperineal approach is introduced. The feasibility of the overall system was evaluated through in vitro phantom experiments under an MRI guidance. The in vitro experiments performed using a certified prostate phantom (incorporating MRI visible lesions). MRI experiments showed that overall hydraulic biopsy needle delivery system has excellent MRI compatibility (signal to noise ratio (SNR) loss &lt; 3%), provides acceptable targeting accuracy (average 2.05±0.46 mm) and procedure time (average 40 min).

Comparative Study of Monoexponential, Intravoxel Incoherent Motion, Kurtosis, and IVIM-Kurtosis Models for the Diagnosis and Aggressiveness Assessment of Prostate Cancer

Objective: This study aimed to compare the potential of monoexponential model (MEM), intravoxel incoherent motion (IVIM) model, kurtosis model, and IVIM–kurtosis model in the diagnosis and aggressiveness assessment of prostate cancer (PCa).

Materials and Methods: Thirty-six patients were recruited. Diffusion-weighted images were acquired on a 3.0-T magnetic resonance imaging (MRI) system using 0 b values up to 2,000 s/mm² and analyzed using four models: MEM (ADC_MEM), IVIM (D_IVIM, D*_IVIM, f_IVIM), kurtosis (D_kurtosis, K_kurtosis), and IVIM–kurtosis (D_{IVIM−kurtosis}, D^*_{IVIM−kurtosis}, f_{IVIM−kurtosis}, D_{IVIM−kurtosis}) models. The values of these parameters were calculated and compared between PCa, benign prostatic hyperplasia (BPH), and prostatitis. Correlations between these parameters and the Gleason score (GS) of PCa were evaluated using the Pearson test.

Results: Forty-five lesions were studied, including 18 PCa, 12 prostatitis, and 15 BPH lesions. The ADC_MEM, D_IVIM, f_IVIM, D_kurtosis, and D_{IVIM−kurtosis} values were significantly lower and K_kurtosis and K_{IVIM−kurtosis} values were significantly higher in PCa compared with prostatitis and BPH. The area under the curve (AUC) of ADC_MEM showed significantly higher values than that of f_IVIM and K_{IVIM−kurtosis}, but no statistical differences were found between the other parameters. The D^*_{IVIM−kurtosis} value correlated negatively and f_{IVIM−kurtosis} and K_{IVIM−kurtosis} values correlated positively with the GS.

Conclusion: The MEM, IVIM, kurtosis, and IVIM–kurtosis models were all useful for the diagnosis of PCa, and the diagnostic efficacy seemed to be similar. The IVIM–kurtosis model may be superior to the MEM, IVIM, and kurtosis models in the grading of PCa.

MultiParametric Magnetic Resonance Imaging-Based Nomogram for Predicting Prostate Cancer and Clinically Significant Prostate Cancer in Men Undergoing Repeat Prostate Biopsy

OBJECTIVE

To develop and internally validate nomograms based on multiparametric magnetic resonance imaging (mpMRI) to predict prostate cancer (PCa) and clinically significant prostate cancer (csPCa) in patients with a previous negative prostate biopsy.

MATERIALS AND METHODS

The clinicopathological parameters of 231 patients who underwent a repeat systematic prostate biopsy and mpMRI were reviewed. Based on Prostate Imaging and Reporting Data System, the mpMRI results were assigned into three groups: Groups "negative," "suspicious," and "positive." Two clinical nomograms for predicting the probabilities of PCa and csPCa were constructed. The performances of nomograms were assessed using area under the receiver operating characteristic curves (AUCs), calibrations, and decision curve analysis.

RESULTS

The median PSA was 15.03 ng/ml and abnormal DRE was presented in 14.3% of patients in the entire cohort. PCa was detected in 75 patients (32.5%), and 59 (25.5%) were diagnosed with csPCa. In multivariate analysis, age, prostate-specific antigen (PSA), prostate volume (PV), digital rectal examination (DRE), and mpMRI finding were significantly independent predictors for PCa and csPCa (all p < 0.01). Of those patients diagnosed with PCa or csPCa, 20/75 (26.7%) and 18/59 (30.5%) had abnormal DRE finding, respectively. Two mpMRI-based nomograms with super predictive accuracy were constructed (AUCs = 0.878 and 0.927, p < 0.001), and both exhibited excellent calibration. Decision curve analysis also demonstrated a high net benefit across a wide range of probability thresholds.

CONCLUSION

mpMRI combined with age, PSA, PV, and DRE can help predict the probability of PCa and csPCa in patients who underwent a repeat systematic prostate biopsy after a previous negative biopsy. The two nomograms may aid the decision-making process in men with prior benign histology before the performance of repeat prostate biopsy.

Management of men with previous negative prostate biopsy

PURPOSE OF REVIEW

Up to 70% of prostate biopsies are negative in men with suspected prostate cancer. Because of inherent limitations in biopsy strategies, a significant proportion of cancers are missed on initial biopsy. Following negative biopsy, men frequently exhibit persistently elevated prostate-specific antigen - raising concerns for missed diagnosis. We highlight the recent updates in the management of negative prostate biopsy.

RECENT FINDINGS

Advances in noninvasive diagnostics are available and assist clinicians in further substratifying risk of prostate cancer. Despite limited data, urinary prostate cancer antigen 3 and transmembrane protease serine 2 appear to have a promising predictive value for patients suspected of prostate cancer. The advent of multiparametricMRI allows the visualization of intermediate and high-grade prostate cancer, particularly in the troublesome anterior prostate. This modality may further provide the potential for magnetic resonance-guided targeted biopsies. Current data suggest that in the presence of suspicious radiological findings, magnetic resonance-guided biopsies have superior sensitivity profiles compared with traditional rebiopsy approaches. In the absence of multiparametricMRI or suspicious findings, traditional saturation biopsies are sufficient.

SUMMARY

The management of negative biopsies is evolving rapidly with emerging diagnostics to stratify risk of prostate cancer in men with previous negative biopsies. An increasing body of information supports the use of magnetic resonance-guided biopsies.

Safety and Feasibility of Direct Magnetic Resonance Imaging-guided Transperineal Prostate Biopsy Using a Novel Magnetic Resonance Imaging-safe Robotic Device

OBJECTIVE

To evaluate safety and feasibility in a first-in-human trial of a direct magnetic resonance imaging (MRI)-guided prostate biopsy using a novel robotic device.

METHODS

MrBot is an MRI-safe robotic device constructed entirely with nonconductive, nonmetallic, and nonmagnetic materials and developed by our group. A safety and feasibility clinical trial was designed to assess the safety and feasibility of a direct MRI-guided biopsy with MrBot and to determine its targeting accuracy. Men with elevated prostate-specific antigen levels, prior negative prostate biopsies, and cancer-suspicious regions (CSRs) on MRI were enrolled in the study. Biopsies targeting CSRs, in addition to sextant locations, were performed.

RESULTS

Five men underwent biopsy with MrBot. Two men required Foley catheter insertion after the procedure, with no other complications or adverse events. Even though this was not a study designed to detect prostate cancer, biopsies confirmed the presence of a clinically significant cancer in 2 patients. On a total of 30 biopsy sites, the robot achieved an MRI-based targeting accuracy of 2.55 mm and a precision of 1.59 mm normal to the needle, with no trajectory corrections and no unsuccessful attempts to target a site.

CONCLUSION

Robot-assisted MRI-guided prostate biopsy appears safe and feasible. This study confirms that a clinically significant prostate cancer (≥5-mm radius, 0.5 cm³) depicted in MRI may be accurately targeted. Direct confirmation of needle placement in the CSR may present an advantage over fusion-based technology and gives more confidence in a negative biopsy result. Additional study is warranted to evaluate the efficacy of this approach.

MR-targeted TRUS prostate biopsy using local reference augmentation: initial experience

Purpose

To evaluate MR-targeted TRUS prostate biopsy using a novel local reference augmentation method.

Patients and methods

Tracker-based MR–TRUS fusion was applied using local reference augmentation. In contrast to conventional whole gland fusion, local reference augmentation focuses the highest registration accuracy to the region surrounding the lesion to be biopsied. Pre-acquired multi-parametric MR images (mpMRI) were evaluated using PIRADS classification. T2-weighted MR images were imported on an ultrasound machine to allow for MR–TRUS fusion. Biopsies were targeted to the most suspicious lesion area identified on mpMRI. Each target was biopsied 1–5 times. For each biopsied lesion the diameter, PIRADS and Gleason scores, visibility during fusion, and representativeness were recorded.

Results

Included were 23 consecutive patients with 25 MR suspicious lesions, of which 11 patients had a previous negative TRUS-guided biopsy and 12 were biopsy naïve. The cancer detection rate was 64 % (Gleason score ≥6). Biopsy was negative (i.e., no Gleason score) in seven patients confirmed by follow-up in all of them (up to 18 months). After MR–TRUS fusion, 88 % of the lesions could be visualized on TRUS. The cancer detection rate increases with increasing lesion size, being 73 % for lesions larger than 10 mm.

Conclusion

Tracker-based MR–TRUS fusion biopsy with local reference augmentation is feasible, especially for lesions with an MR maximum diameter of at least 10 mm or PIRADS 5 lesions. If this is not the case, we recommend in-bore MR-guided biopsy.

Misclassification of outcome in case-control studies: Methods for sensitivity analysis

Case-control studies are potentially open to misclassification of disease outcome which may be unrelated to risk factor exposure (non-differential), thus underestimating associations, or related to risk factor exposure (differential), thus causing more serious bias.We conducted a systematic literature review for methods of adjusting for outcome misclassification in case-control studies. We also applied methods to simulated data with known outcome misclassification to assess performance of these methods. Finally, real data from the Prostate Testing for Cancer and Treatment (ProtecT) randomised controlled trial gauged the usefulness of these methods.Adjustment methods range from recalculating cell frequencies to probabilistic sensitivity modelling and Bayesian models, which incorporate uncertainty in sensitivity and specificity estimates. Simulated data indicated that substantial bias in either direction resulted from differential misclassification. More sophisticated methods, incorporating uncertainty into estimates of misclassification, provided appropriately wide confidence intervals for corrected estimates of risk factor-disease association.Method choice depends on whether the objective is to assess if an observed association can be explained by bias, or to provide a 'corrected' estimate for the primary analysis. Accurate estimation of the degree of misclassification is important for the latter; otherwise further bias may be introduced.

Automated real-time needle-guide tracking for fast 3-T MR-guided transrectal prostate biopsy: a feasibility study

PURPOSE

To assess the feasibility of automatic needle-guide tracking by using a real-time phase-only cross correlation ( POCC phase-only cross correlation ) algorithm-based sequence for transrectal 3-T in-bore magnetic resonance (MR)-guided prostate biopsies.

MATERIALS AND METHODS

This study was approved by the ethics review board, and written informed consent was obtained from all patients. Eleven patients with a prostate-specific antigen level of at least 4 ng/mL (4 μg/L) and at least one transrectal ultrasonography-guided biopsy session with negative findings were enrolled. Regions suspicious for cancer were identified on 3-T multiparametric MR images. During a subsequent MR-guided biopsy, the regions suspicious for cancer were reidentified and targeted by using the POCC phase-only cross correlation -based tracking sequence. Besides testing a general technical feasibility of the biopsy procedure by using the POCC phase-only cross correlation -based tracking sequence, the procedure times were measured, and a pathologic analysis of the biopsy cores was performed.

RESULTS

Thirty-eight core samples were obtained from 25 regions suspicious for cancer. It was technically feasible to perform the POCC phase-only cross correlation -based biopsies in all regions suspicious for cancer in each patient, with adequate biopsy samples obtained with each biopsy attempt. The median size of the region suspicious for cancer was 8 mm (range, 4-13 mm). In each region suspicious for cancer (median number per patient, two; range, 1-4), a median of one core sample per region was obtained (range, 1-3). The median time for guidance per target was 1.5 minutes (range, 0.7-5 minutes). Nineteen of 38 core biopsy samples contained cancer.

CONCLUSION

This study shows that it is feasible to perform transrectal 3-T MR-guided biopsies by using a POCC phase-only cross correlation algorithm-based real-time tracking sequence.

MRI-safe robot for targeted transrectal prostate biopsy: animal experiments

OBJECTIVES

To study the feasibility and safety of using a magnetic resonance imaging (MRI)-safe robot for assisting MRI-guided transrectal needle placement and biopsy in the prostate, using a canine model. To determine the accuracy and precision afforded by the use of the robot while targeting a desired location in the organ.

MATERIALS AND METHODS

In a study approved by the Institutional Animal Care and Use Committee, six healthy adult male beagles with prostates of at least 15 × 15 mm in size at the largest transverse section were chosen for the procedure. The probe portion of the robot was placed into the rectum of the dog, images were acquired and image-to-robot registration was performed. Images acquired after placement of the robot were reviewed and a radiologist selected targets for needle placement in the gland. Depending on the size of the prostate, up to a maximum of six needle placements were performed on each dog. After needle placement, robot-assisted core biopsies were performed on four dogs that had larger prostate volumes and extracted cores were analysed for potential diagnostic value.

RESULTS

Robot-assisted MRI-guided needle placements were performed to target a total of 30 locations in six dogs, achieving a targeting accuracy of 2.58 mm (mean) and precision of 1.31 mm (SD). All needle placements were successfully completed on the first attempt. The mean time required to select a desired target location in the prostate, align the needle guide to that point, insert the needle and perform the biopsy was ∼ 3 min. For this targeting accuracy study, the inserted needle was also imaged after its placement in the prostate, which took an additional 6-8 min. Signal-to-noise ratio analysis indicated that the presence of the robot within the scanner bore had minimal impact on the quality of the images acquired. Analysis of intact biopsy core samples indicated that the samples contained prostatic tissues, appropriate for making a potential diagnosis. Dogs used in the study did not experience device- or procedure-related complications.

CONCLUSIONS

Results from this preclinical pilot animal study suggest that MRI-targeted transrectal biopsies are feasible to perform and this procedure may be safely assisted by an MRI-safe robotic device.

Feasibility of a pneumatically actuated MR-compatible robot for transrectal prostate biopsy guidance

PURPOSE

To assess the feasibility of using a remote-controlled, pneumatically actuated magnetic resonance (MR)-compatible robotic device to aid transrectal biopsy of the prostate performed with real-time 3-T MR imaging guidance.

MATERIALS AND METHODS

This prospective study was approved by the ethics review board, and written informed consent was obtained from all patients. Twelve consecutive men who were clinically suspected of having prostate cancer and had a history of at least one transrectal ultrasonography (US)-guided prostate biopsy with negative results underwent diagnostic multiparametric MR imaging of the prostate. Two radiologists in consensus identified cancer-suspicious regions (CSRs) in 10 patients. These regions were subsequently targeted with the robot for MR imaging-guided prostate biopsy. To direct the needle guide toward the CSRs, the MR-compatible robotic device was remote controlled at the MR console by means of a controller and a graphical user interface for real-time MR imaging guidance of the needle guide. The ability to reach the CSRs with the robot for biopsy was analyzed.

RESULTS

A total of 17 CSRs were detected in 10 patients at the diagnostic MR examinations. These regions were targeted for MR imaging-guided robot-assisted prostate biopsy. Thirteen (76%) of the 17 CSRs could be reached with the robot for biopsy. Biopsy of the remaining four CSRs was performed without use of the robot.

CONCLUSION

It is feasible to perform transrectal prostate biopsy with real-time 3-T MR imaging guidance with the aid of a remote-controlled, pneumatically actuated MR-compatible robotic device.

Urinary proteomics: ready for prime time in urological cancer diagnostics?

The impact of clinical proteomics on the diagnosis and treatment of urological malignancies is modest in comparison with the high expectations of the past. However, most available studies suffer from flawed clinical designs rather than from technical limitations. This article will briefly introduce the main technological approaches taken, their advantages and disadvantages and will highlight the different challenges associated with urinary proteome analysis. Furthermore, several examples of the successful application of urinary clinical proteomics in the field of prostate and bladder cancer will be introduced. These examples suggest careful validation of novel biomarkers, appropriate study designs using blinded cohorts enrolled from appropriate target populations and the standardization of techniques as key elements required for successful urinary proteomics studies. These prerequisites are essential for turning the old promise of a personalized medicine approach into a new reality to optimize patients’ preventive and therapeutic care.

Fluorescence time-resolved imaging system embedded in an ultrasound prostate probe

Ultrasound imaging (US) of the prostate has a low specificity to distinguish tumors from the surrounding tissues. This limitation leads to systematic biopsies. Fluorescent diffuse optical imaging may represent an innovative approach to guide biopsies to tumors marked with high specificity contrast agents and therefore enable an early detection of prostate cancer. This article describes a time-resolved optical system embedded in a transrectal US probe, as well as the fluorescence reconstruction method and its performance. Optical measurements were performed using a pulsed laser, optical fibers and a time-resolved detection system. A novel fast reconstruction method was derived and used to locate a 45 µL ICG fluorescent inclusion at a concentration of 10 µM, in a liquid prostate phantom. Very high location accuracy (0.15 cm) was achieved after reconstruction, for different positions of the inclusion, in the three directions of space. The repeatability, tested with ten sequential measurements, was of the same order of magnitude. Influence of the input parameters (optical properties and lifetime) is presented. These results confirm the feasibility of using optical imaging for prostate guided biopsies.

MR imaging-guided interventions in the genitourinary tract: an evolving concept

MR imaging-guided interventions are well established in routine patient care in many parts of the world. There are many approaches, depending on magnet design and clinical need, based on MR imaging providing excellent inherent tissue contrast without ionizing radiation risk for patients. MR imaging-guided minimally invasive therapeutic procedures have advantages over conventional surgical procedures. In the genitourinary tract, MR imaging guidance has a role in tumor detection, localization, and staging and can provide accurate image guidance for minimally invasive procedures. The advent of molecular and metabolic imaging and use of higher strength magnets likely will improve diagnostic accuracy and allow targeted therapy to maximize disease control and minimize side effects.

Endoclipping treatment of life-threatening rectal bleeding after prostate biopsy

Rectal bleeding is frequently seen in patients undergoing transrectal ultrasound (TRUS)-guided multiple biopsy of the prostate, but is usually mild and stops spontaneously. We report what is believed to be the first case of life-threatening rectal bleeding following this procedure, which was successfully treated by endoscopic intervention through placement of three clips on the sites of bleeding. This case emphasizes endoscopic intervention associated with endoclipping as a safe and effective method to achieve hemostasis in massive rectal bleeding after prostate biopsy. Additionally, current data on the complications of the TRUS-guided multiple biopsy of the prostate and the options for treating fulminant rectal bleeding, a consequence of this procedure, are described.

MR imaging-guided interventions in the genitourinary tract: an evolving concept

MR imaging-guided interventions are well established in routine patient care in many parts of the world. There are many approaches, depending on magnet design and clinical need, based on MR imaging providing excellent inherent tissue contrast without ionizing radiation risk for patients. MR imaging-guided minimally invasive therapeutic procedures have advantages over conventional surgical procedures. In the genitourinary tract, MR imaging guidance has a role in tumor detection, localization, and staging and can provide accurate image guidance for minimally invasive procedures. The advent of molecular and metabolic imaging and use of higher strength magnets likely will improve diagnostic accuracy and allow targeted therapy to maximize disease control and minimize side effects.

Identification of PCA3 (DD3) in prostatic carcinoma by in situ hybridization

PCA3 is a specific marker of prostatic carcinoma. However, PCA3 has been detected only at RNA level and a corresponding PCA3 protein has never been identified. The aim of this study was to develop a technique capable of detecting PCA3 RNA on histology sections and to assess the cellular location of the molecule. Forty-eight formalin-fixed paraffin-embedded blocks of prostatectomy specimens were selected for PCA3 detection by in situ hybridization by both radioactive and chromogenic methods. Of the 48 sections, 28 contained prostatic adenocarcinoma and 20 had benign tissue located distant from the tumor. Using the radioactive detection method, 26 of 28 available cases (93%) of cancers presented at least focal cytoplasmic PCA3 expression. The benign glands located in proximity of the cancer presented PCA3 expression in eight (29%) cases, whereas those situated distant to the tumor showed focal expression in 2 of 20 (10%) cases only. High-grade prostatic intraepithelial neoplasia (HGPIN) expressed PCA3 in 25 of 26 (96%) cases. With the chromogenic detection method, 22 of the 24 interpretable cases (92%) of cancers had at least focal cytoplasmic staining. Benign glands located close to neoplastic glands expressed PCA3 in 8 (33%) cases, but none of those distant to the tumor expressed the marker. HGPIN was positive in 17 of 24 (71%) cases. The sensitivity, specificity, positive predictive value and negative predictive value for the detection of cancer were 93, 79, 71 and 95% for the radioactive detective method and 92, 80, 71 and 95% for the chromogenic detection method, respectively. Our study shows that PCA3 RNA is expressed by most prostate cancers and HGPIN. Normal glands rarely express the marker, except those located in immediate proximity of neoplastic glands, suggesting the presence of precursor molecular changes.

Contrast enhanced ultrasound flash replenishment method for directed prostate biopsies

PURPOSE

We evaluated prostate cancer detection with contrast enhanced ultrasound of the prostate using MicroFlow Imaging (Toshiba America Medical Systems, Tustin, California) compared to systematic biopsy.

MATERIALS AND METHODS

A total of 60 patients referred for prostate biopsy were evaluated with pre-contrast and contrast enhanced MicroFlow Imaging transrectal ultrasound. MicroFlow Imaging is a flash replenishment technique that uses high power flash pulses to destroy contrast microbubbles, followed by low power pulses to demonstrate contrast replenishment. A composite image depicting the vascular architecture is constructed through maximum intensity capture of temporal data in consecutive low power images. Using MicroFlow Imaging up to 5 directed biopsy cores were obtained from areas of abnormal vascular enhancement or morphology, followed by a systematic 10-core biopsy protocol.

RESULTS

A biopsy positive for cancer was found in 79 of the 825 cores (10%) from 18 of the 60 subjects (30%). Positive biopsies were obtained in 50 of 600 systematic core biopsies (8.3%) and in 29 of 225 directed cores (13%) (OR 2.02, p = 0.034). Five of the 18 patients diagnosed with cancer were identified only by systematic biopsy, 2 were identified only by directed biopsy with MicroFlow Imaging and 11 were identified by the 2 techniques (p >0.25). Twice the number of patients was detected per core with directed vs systematic biopsy (0.058 vs 0.027).

CONCLUSIONS

The vascular detail provided by MicroFlow Imaging allowed directed biopsy of these areas with increased detection of prostate cancer. Although a minority of cancers were not detected with MicroFlow Imaging directed biopsy, this technique detected twice as many patients with prostate cancer per biopsy core.

Transperineal prostate biopsy under magnetic resonance image guidance: a needle placement accuracy study

PURPOSE

To quantify needle placement accuracy of magnetic resonance image (MRI)-guided core needle biopsy of the prostate.

MATERIALS AND METHODS

A total of 10 biopsies were performed with 18-gauge (G) core biopsy needle via a percutaneous transperineal approach. Needle placement error was assessed by comparing the coordinates of preplanned targets with the needle tip measured from the intraprocedural coherent gradient echo images. The source of these errors was subsequently investigated by measuring displacement caused by needle deflection and needle susceptibility artifact shift in controlled phantom studies. Needle placement error due to misalignment of the needle template guide was also evaluated.

RESULTS

The mean and standard deviation (SD) of errors in targeted biopsies was 6.5 +/- 3.5 mm. Phantom experiments showed significant placement error due to needle deflection with a needle with an asymmetrically beveled tip (3.2-8.7 mm depending on tissue type) but significantly smaller error with a symmetrical bevel (0.6-1.1 mm). Needle susceptibility artifacts observed a shift of 1.6 +/- 0.4 mm from the true needle axis. Misalignment of the needle template guide contributed an error of 1.5 +/- 0.3 mm.

CONCLUSION

Needle placement error was clinically significant in MRI-guided biopsy for diagnosis of prostate cancer. Needle placement error due to needle deflection was the most significant cause of error, especially for needles with an asymmetrical bevel.

Prostate Biopsy in Central Europe: Results of a Survey of Indication, Patient Preparation and Biopsy Technique

OBJECTIVE

We surveyed urologists in Austria, Germany and Switzerland regarding their standard approach to prostate biopsy.

METHODS

Participants of Austrian and German urological meetings were asked to fill out a survey form; additionally, this was mailed to all Swiss urologists.

RESULTS

304 surveys are available for analysis. 97% of participants perform a biopsy if digital rectal examination is abnormal. 63% use 4 ng/ml PSA (prostate-specific antigen) as cut-off. Age-related reference ranges are used by 54%, free PSA by 57%. 22% use PSA density, 55% PSA velocity. Overall 61% require a written consent, with 85, 86 and 25% in Austria, Germany and Switzerland. 96% of the urologists prescribe a quinolone antibiotic with a wide range regarding the start and end of drug therapy. 77% offer some kind of anaesthesia. Periprostatic injection of a local anaesthetic drug is used by 36%, lidocaine gel by 27%. 91% perform the biopsies transrectally under ultrasound guidance. Digitally guided biopsies are used by 11%. Only 3 participants perform perineal biopsies. The mean number of cores per biopsy session is 9.2, the maximum number of cores is 15.3 as a mean. Participants will stop performing any further biopsies if the patient already had a mean of 3.5 biopsy sessions.

CONCLUSIONS

The majority of urologists in Central Europe prescribe a quinolone antibiotic and recommend some type of analgesia. The majority has abandoned the sextant technique and increases the number of cores in the case of rebiopsy. Biopsies are stopped after a mean of 3.5 sessions.

Impact of additional sampling in the TRUS-guided biopsy for the diagnosis of prostate cancer

AIM

To evaluate the diagnostic value of 10+ systematic sampling technique when performing transrectal ultrasound-guided (TRUS) prostate biopsy, compared with the sextant biopsy technique for patients with suspected prostate cancer.

METHODS

286 patients with suspected prostate cancer were included in the study. Patients were eligible for the study if they had serum levels of prostate-specific antigen (PSA) >4 ng/ml or ratio PSA <0.25 and/or an abnormal digital rectal examination (DRE). The population sample was divided in three groups: (1) those with positive PSA, PSA ratio and DRE (70 patients); (2) those with positive PSA and PSA ratio but normal DRE (178 patients), and (3) those with positive PSA and PSA ratio, positive PSA velocity and a negative biopsy in the previous 6-month period (38 patients). In addition to the conventional sextant prostate biopsy cores, four more biopsies were obtained from the lateral peripheral zone (10 core biopsy protocol). Additional cores (total of 12-14) were also randomly selected in case of larger prostates (>60 ml) or from suspicious foci revealed by transrectal ultrasound. All additional biopsy cores were submitted separately to the pathological department.

RESULTS

Cancer was detected in 55.7% (39/70) and 69% (48/70) of the patients (for sextant core and for the extended biopsy protocols, respectively) in the first study group, 11% (20/178) and 23% (41/178) of the patients (for the sextant and the extended biopsy protocols, respectively) in the second study group, and 42% (16/38) and 63% (24/38) of the patients (for the sextant and the extended biopsy protocols, respectively) in the third study group. The addition of the lateral peripheral zone (PZ) of the prostate to the sextant biopsy showed a 23, 105 and 50% increase in the number of cancers diagnosed in the first, second and third study groups, respectively. The improvement of cancer detection rate (sensitivity) was statistically significant for all groups evaluated.

CONCLUSION

The 10+ systematic TRUS-guided prostate biopsy improves the detection rate of prostate cancer compared to the sextant biopsy technique alone, especially when performed in men with positive PSA, PSA ratio, and negative DRE.

Design and preliminary accuracy studies of an MRI-guided transrectal prostate intervention system

This paper reports a novel system for magnetic resonance imaging (MRI) guided transrectal prostate interventions, such as needle biopsy, fiducial marker placement, and therapy delivery. The system utilizes a hybrid tracking method, comprised of passive fiducial tracking for initial registration and subsequent incremental motion measurement along the degrees of freedom using fiber-optical encoders and mechanical scales. Targeting accuracy of the system is evaluated in prostate phantom experiments. Achieved targeting accuracy and procedure times were found to compare favorably with existing systems using passive and active tracking methods. Moreover, the portable design of the system using only standard MRI image sequences and minimal custom scanner interfacing allows the system to be easily used on different MRI scanners.

Extensive biopsy using a combined transperineal and transrectal approach to improve prostate cancer detection

PURPOSE

Previous studies have indicated that 6-core transrectal prostate biopsy misses a considerable number of cancers. We performed an extensive biopsy protocol of 12-core sampling using both transperineal and transrectal approaches to determine the impact on the cancer detection rate.

MATERIALS AND METHODS

We prospectively evaluated 402 men who underwent 6-core transperineal and 6-core transrectal biopsies simultaneously due to abnormal digital rectal examination (DRE) and/or elevated prostate-specific antigen (PSA) levels of 4.0 ng/mL or greater. Using the transperineal approach we obtained four cores from the bilateral peripheral zone targeting the lateral and parasagittal areas and two cores from the bilateral transition zone. The following transrectal biopsy was performed traditionally. We compared cancer detection rate between the extended 12-core procedure and conventional 6-core transperineal and transrectal groups in terms of total PSA and DRE findings.

RESULTS

Using the extensive combined method, prostate cancer was detected in 195 cases (48.5%) and the detection rate significantly increased 7.2% and 8.5% compared to the transperineal and transrectal groups, respectively. According to PSA levels and DRE findings, the cancer detection rate by the combined method was significantly improved in patients with PSA levels of 4-10 ng/mL and negative DRE: 10.3% and 11.6% compared to the transperineal and transrectal groups, respectively.

CONCLUSIONS

The extensive 12-core method significantly improved the overall cancer detection rate and was especially efficient for men with PSA levels of 4-10 ng/mL accompanied by a negative DRE finding.

Sensitivity and detection rate of a 12-core trans-perineal prostate biopsy: preliminary report

OBJECTIVES

The various prostate biopsy methods are usually compared in terms of the diagnosis rate of prostate cancer. However, the prevalence of cancer in patients with a negative prostatic biopsy is not usually known. We determined the sensitivity and detection rate of 12-core transperineal biopsies in patients not previously investigated for prostate cancer.

METHODS

We performed prostate biopsy in 63 patients (median age 67 years) before radical cystoprostatectomy for high-grade bladder cancer. We then assessed the relationships between biopsy result, prostate cancer in the surgical specimen, and other variables.

RESULTS

17.2% of patients had a positive biopsy and 54% had prostate cancer on definitive histology. Biopsy sensitivity was 32.3% overall, 75% for clinically significant cancers, and 11% for non-significant cancers. Median PSA was 1.2ng/ml, PSA levels did not correlate with the presence of prostate cancer, the presence of clinically significant cancer, bioptic diagnosis, or prostate volume. Age correlated with risk of cancer.

CONCLUSIONS

According to autopsy series, the prevalence of prostate cancer is greater than 50% in males older than 60, yet low PSA levels do not reliably indicate disease absence. The sensitivity of double sextant biopsy is unsatisfactory overall (32%), but acceptable (75%) for diagnosing clinically significant cancer.

A comparison of the diagnostic performance of systematic versus ultrasound-guided biopsies of prostate cancer

Transrectal ultrasound (TRUS) is an important tool for urologists and radiologists in the detection of prostate cancer. Various TRUS-guided biopsy techniques are applied in clinical practice. Frequently, only the detection rates achieved with these methods are compared. Other diagnostic performance parameters, particularly the specificity and negative predictive value, are seldom compared. After extensive assessment of the available literature, this review describes the methods of TRUS-guided biopsy for prostate cancer detection. A distinction was made between systematic biopsies and biopsies that target a perceived (hypoechoic or Doppler-enhancing) lesion on imaging. Subsequently, the diagnostic performance (sensitivity, specificity, positive and negative predictive values, accuracies) was compared between these techniques. Imaging-guided biopsy showed better diagnostic performance than systematic biopsy with higher sensitivity. The combinations of sensitivity and specificity were highest for colour Doppler and contrast-enhanced targeted biopsy. Studies targeting hypoechoic lesions had relatively high sensitivity, but specificity was low. Presently however, with widespread prostate-specific antigen screening, fewer prostate cancers are hypoechoic, and the value of targeting hypoechoic lesions has diminished. Performing colour or contrast-enhanced Doppler biopsy or adding these techniques to systematic biopsies improves diagnostic performance, particularly by increasing sensitivity.

Prostate Biopsy Outcome Using 29 mm Cutting Length

OBJECTIVES

The aim of the study was to compare the prostate biopsy outcome by using either standard or extended cutting length of the needles.

MATERIAL AND METHODS

A total of 74 consecutive prostates from radical prostatectomy were used. Two sextant biopsies were performed ex vivo. We developed a precise simulation of a transrectal biopsy procedure using ultrasound for guiding the needle. In the first set of biopsies an 18-gauge tru cut needle with 19 mm cutting length, powered by a automatic biopsy gun was used. In the second set a single use gun with an 18-gauge end-cutting needle and 29 mm cutting length was used.

RESULTS

In the set of sextant biopsies using 19 mm cutting length 49 (66%) carcinomas were found. In the set of sextant biopsies using 29 mm cutting length 58 (78%) of the tumors were detected. 24 (32%) prostates showed tumor in the transition zones, but there was no transition-zone-only cancer in this study. Nevertheless taking longer cores led to an improvement in prostate cancer detection of 18%.

CONCLUSIONS

In this ex vivo setting the use of 29 mm cutting length for prostate biopsy led to an significant improvement in cancer detection. As we found the end-cutting needle not suitable for use in the patient, these results support the idea to develop a longer tru cut needle and corresponding gun for further clinical investigations.

Optimization of prostatic biopsy: a prospective randomized trial comparing the sextant biopsy with a 10-core biopsy. Impact of prostatic region of sampling

OBJECTIVE

New prostatic biopsy protocols suggest to increase the core numbers to enhance detection. Additional cores are usually sampled from the lateral part of the p-zone. We direct the sextant biopsy to the most lateral part of the p-zone, therefore we investigated if there is a gain by adding 4 median biopsy cores.

MATERIAL AND METHODS

The prospective randomized trial (n = 200) compared our modified sextant biopsy to a 10-core strategy with 2 additional median cores on both sides. Directed biopsies to suspicious areas were allowed in both groups. Morbidity was assessed by a self-administered questionnaire.

RESULTS

PC detection was 32% for 6 cores and 40% for 10 cores. Four patients were detected only by median biopsies. Using the binomial distribution table the gain of 4% is statistically significant. There was no statistical difference in morbidity, but a trend towards a higher rate of side effects in the 10-core group.

CONCLUSIONS

The gain in prostate cancer detection rate by additional median biopsies is low, but statistically significant. There is no difference in morbidity and patient acceptance is high, therefore we favor the 10-core biopsy in our patients.

Clinical relevance of genetic instability in prostatic cells obtained by prostatic massage in early prostate cancer

We investigated whether genetic lesions such as loss of heterozygosity (LOH) are detected in prostatic cells obtained by prostatic massage during early diagnosis of prostate cancer (CaP) and discussed their clinical relevance. Blood and first urine voided after prostatic massage were collected in 99 patients with total prostate-specific antigen (PSA) between 4 and 10 ng ml⁻¹, prior to prostate biopsies. Presence of prostatic cells was confirmed by quantitative RT–PCR analysis of PSA mRNA. Genomic DNA was analysed for LOH on six chromosomal regions. One or more allelic deletions were found in prostatic fluid from 57 patients analysed, of whom 33 (58%) had CaP. Sensitivity and specificity of LOH detection and PSA free to total ratio <15% for positive biopsy were respectively 86.7 and 44% (P=0.002) for LOH, and 55 and 74% (P=0.006) for PSA ratio <15%. Analysis of LOH obtained from prostatic tumours revealed similar patterns compared to prostatic fluid cells in 86% of cases, confirming its accuracy. The presence of LOH of urinary prostatic cells obtained after prostatic massage is significantly associated with CaP on biopsy and may potentially help to identify a set of patients who are candidates for further prostate biopsies.

Design of a novel MRI compatible manipulator for image guided prostate interventions

This paper reports a novel remotely actuated manipulator for access to prostate tissue under magnetic resonance imaging guidance (APT-MRI) device, designed for use in a standard high-field MRI scanner. The device provides three-dimensional MRI guided needle placement with millimeter accuracy under physician control. Procedures enabled by this device include MRI guided needle biopsy, fiducial marker placements, and therapy delivery. Its compact size allows for use in both standard cylindrical and open configuration MRI scanners. Preliminary in vivo canine experiments and first clinical trials are reported.

Functional Characterization of Prostate Cancer by Integrated Magnetic Resonance Imaging and Oxygenation Changes During Carbogen Breathing

OBJECTIVE

The objective of this study was to evaluate the changes in oxygenation of prostate cancer induced by carbogen breathing using blood oxygen level-dependent (BOLD) magnetic resonance image (MRI) with an endorectal coil (eMRI).

MATERIALS AND METHODS

In 32 patients with biopsy-proven prostate cancer, endorectal MRI was performed at 1.5 Tesla using the BOLD method. Images were acquired during 4 x 4-minute episodes alternating between room air and carbogen (95% O2/5% CO2) breathing. In each episode, 40 images were acquired (T2*-weighted EPI sequence, 12-14 slices, 3-mm thickness). All patients underwent radical prostatectomy; BOLD-MRI findings were correlated with the histopathologic results.

RESULTS

BOLD-MRI could be evaluated in 29 patients, and revealed heterogeneous signal changes of normal prostate and cancer tissue similar to the heterogeneity of prostate tissue in anatomic/pathologic preparation. A significant signal intensity increase (P = 0.004) was found in normal central gland and peripheral zone during carbogen breathing. Signal enhancement in carcinoma was significantly lower (P = 0.004) compared with the contralateral normal side.

CONCLUSION

Intrinsic blood-tissue contrast-functional MRI during carbogen breathing may help detect and characterize prostate carcinoma from normal tissue, particularly in small 1-sided carcinomas. This may be useful for identifying candidates for radiotherapy and monitoring noninvasive therapeutic approaches.

Bleeding after transrectal ultrasonography-guided prostate biopsy: a study of 7-day morbidity after a six-, eight- and 12-core biopsy protocol

OBJECTIVE

To compare, in a prospective study, bleeding (in three categories, i.e. haematuria, haematospermia and rectal) and consultations with the general practitioner (GP), after a six-, eight- or 12-core prostate biopsy, as data on whether taking more prostate core biopsies increases bleeding complications are not conclusive.

PATIENTS AND METHODS

Over a 5-year period, patients undergoing outpatient transrectal ultrasonography (TRUS)-guided prostate biopsy (six, eight or 12-core biopsy) completed a self-administered questionnaire. The prevalence and duration of the three bleeding complications and GP or hospital visits for a biopsy-related complication were assessed and compared for the 7 days after biopsy. The contribution of local anaesthetic (LA) injection to bleeding rates was also assessed.

RESULTS

Of 1384 patients biopsied, 1000 were given questionnaires and 884 (88%) forms were returned. Of these, 760 were suitable for analysis (307 after six-core, 325 eight-core and 128 12-core biopsies); 351 patients were given LA before biopsy. The prevalence of bleeding complications (six-, eight- and 12-core, respectively) was: haematuria 44%, 41% and 39%; haematospermia 13%, 16% and 12%; and rectal bleeding 17%, 26% and 27%. Rectal bleeding was significantly more prevalent in the eight- and 12-core groups (P = 0.0037 and 0.019). The duration of bleeding was not significantly greater in any biopsy group. Subgroup analysis showed no significant difference in the prevalence and duration of rectal bleeding after LA. About 5% of patients in each group consulted their GP because of a complication and 2.4% consulted because of bleeding. Three men with major complications required hospitalization, of which only one was caused by bleeding.

CONCLUSIONS

Only rectal bleeding was more prevalent after taking more than six cores, but the duration was no greater. Giving LA did not affect the rectal bleeding rate. With all strategies the major complication and hospitalization rate was very low.

Influence of transrectal ultrasound probe on prostate cancer detection in transrectal ultrasound-guided sextant biopsy of prostate

OBJECTIVES

To determine whether end-fire probes increase the prostate cancer (PCa) detection rate. Enhancing the PCa detection rate is the main goal of biopsy protocols. Prostate biopsy is limited by side-fire probes to a longitudinal axis, but end-fire probes allow biopsy cores to also be taken in the transverse section.

METHODS

A total of 2625 patients underwent systematic sextant biopsy in three institutions using the same protocol. Three different ultrasound probes were used-the Kretz Combisone and Bruel & Kjaer side-fire probes and the ATL HDI end-fire probe. We retrospectively evaluated the influence of the probe on the PCa detection rate.

RESULTS

The Kretz probe was used in 384 men, the Bruel & Kjaer probe in 598 men, and the ATL probe in 1643 men. Overall, 35.2% had PCa detected. Analyzing all patients, no statistically significant difference (P = 0.73) was found for the probes, but the subgroup with a prostate-specific antigen level of 4 to 10 ng/mL demonstrated a statistically significant improvement in the detection rate using the end-fire probe (31.3% versus 24.5% and 21.5% for the side-fire probes, P = 0.01). Patients with nonpalpable PCa also demonstrated a statistically significant increase in detection with the end-fire probe (P = 0.004). Multivariate analysis confirmed that the ultrasound probe is an independent parameter to enhance the PCa detection rate.

CONCLUSIONS

Our results showed that end-fire probes provide a statistically significant improvement in the PCa detection rate compared with side-fire probes in patients with a prostate-specific antigen level of 4 to 10 ng/mL and nonpalpable disease. The reason could be the facilitated sampling in the most lateral part of the peripheral zone. Our results suggest that the widespread use of end-fire probes for prostate biopsy could enhance the PCa detection rate.

Do younger men have better biochemical outcomes after radical prostatectomy?

OBJECTIVES

To examine the relationship between age and biochemical failure after radical prostatectomy (RP), controlling for the year of surgery. Prior studies have suggested that younger men have lower prostate-specific antigen recurrence rates after RP, although none of the prior studies had controlled for the year of surgery.

METHODS

We examined the data from 1753 men treated with RP between 1988 and 2002 at five equal access medical centers. We compared age, as a categorical variable according to decade of life (50 years old or younger, 51 to 60, 61 to 70, and older than 70 years), with the clinical and pathologic variables at RP, as well as the time to biochemical recurrence, using a multivariate Cox proportional hazards model.

RESULTS

Age was significantly related to the year of surgery, with the more recently treated patients being younger than less recently treated patients (P <0.001). After controlling for the year of surgery, the younger men had smaller prostates, fewer high-grade tumors on biopsy, and less lymph node metastasis, but a greater percentage of cores with cancer. On multivariate analysis, men 50 years old or younger had significantly lower recurrence rates than did the older men. Moreover, men older than 70 years had significantly greater prostate-specific antigen failure rates than men aged 51 to 70 years or men aged 50 years or younger.

CONCLUSIONS

The average age of men undergoing RP has decreased with time. Independent of this, young men have more favorable outcomes after RP than older men. Continued screening to detect prostate cancer among younger men when it is most curable appears warranted.

Is there a difference in outcome after radical prostatectomy between patients with biopsy Gleason sums 4, 5, and 6? Results from the SEARCH database

PURPOSE

Fewer patients newly diagnosed with prostate cancer today have biopsy Gleason sums <6 compared to several years ago. Several tables and nomograms for predicting disease recurrence after definitive therapy provide little or no discrimination between biopsy Gleason sums 4, 5, and 6. We sought to examine the significance of biopsy Gleason sum for predicting biochemical failure following radical prostatectomy (RP) for men with biopsy Gleason sums of 4, 5, and 6.

MATERIALS AND METHODS

We examined data from 988 men treated with RP between 1988 and 2002 who had biopsy Gleason sums of 4-6. Clinical and pathological variables as well as outcome information were compared between men with biopsy Gleason sums of 4-6. The log-rank and Cox proportional hazards analysis were used to determine whether biopsy Gleason sum provided unique prognostic information for men with low biopsy Gleason sums undergoing RP.

RESULTS

There was statistically significant, but overall weak correlation between biopsy Gleason sum and Gleason sum of the RP specimen (Spearman's r=0.277, P<0.001). As biopsy Gleason sum increased from 4 to 5 to 6, there was a steady rise (HR=1.31 for each one point increase in Gleason sum, Cox's model) in the risk of PSA failure (P=0.025, log-rank). On multivariate analysis comparing biopsy Gleason sum, preoperative PSA, clinical stage, year of surgery, percent of biopsy cores positive, and age for their ability to predict time to biochemical recurrence, only PSA (HR 2.09, CI 1.56-2.80, P<0.001) and biopsy Gleason sum (HR 1.33, CI 1.05-1.70, P=0.019) were significant independent predictors of PSA failure.

CONCLUSIONS

Despite weak correlation between biopsy and pathologic Gleason sum among men with biopsy Gleason sum 4-6 tumors, grade was a significant independent predictor of PSA failure following RP. In the range of 4-6, biopsy Gleason sum acted as a continuous variable for predicting PSA failure. The routine use of Gleason sums 4 and 5 to grade prostate needle biopsy specimens should not be abandoned.

Morbidity of Prostatic Biopsy for Different Biopsy Strategies: Is There a Relation to Core Number and Sampling Region?

OBJECTIVES

The standard sextant prostatic biopsy is a safe procedure associated with low morbidity. Newer biopsy protocols suggest an increase in core numbers or sampling in distinct areas. In this respect we investigated the morbidity of different biopsy regimens.

METHODS

Morbidity was assessed using self-administered questionnaires 1 week and 1 month after biopsy in a prospective randomized trial of 405 men with three different biopsy protocols. We compared a sextant biopsy regimen to a 10-core biopsy strategy, as well as patients with a re-biopsy including t-zone sampling. We investigated pain during and after biopsy, gross hematuria, rectal bleeding, hematospermia, fever and chills.

RESULTS

There is a trend towards a more painful biopsy and higher rate of side effects if the number of core samples is increased, this difference did not reach statistical significance. There was no increase in severity of side effects. Regarding the rate and severity of side effects of biopsy strategies to different areas of the prostate we could not find a difference. About 95% of patients would accept a repeat biopsy based on their experience on first biopsy.

CONCLUSIONS

Morbidity of transrectal prostatic biopsy is low and increasing the number of cores correlates with a minor and statistically not significant increase in the rate of side effects. Transrectal sextant prostatic biopsy and extensive biopsy protocols are generally well tolerated and widely accepted from patients.

Impact of obesity on biochemical control after radical prostatectomy for clinically localized prostate cancer: a report by the Shared Equal Access Regional Cancer Hospital database study group

PURPOSE

Given the limited information regarding the impact of obesity on treatment outcomes for prostate cancer, we sought to examine the relationship between body mass index (BMI) and cancer control after radical prostatectomy (RP).

PATIENTS AND METHODS

We compared clinicopathologic and biochemical outcome information across BMI groups from 1,106 men treated with RP between 1988 and 2002. Multivariate analysis was used to determine if BMI significantly predicted adverse pathology or biochemical recurrence.

RESULTS

Obesity was related to year of surgery (P <.001) and race (P <.001), with black men having the highest obesity rates. Obese patients had higher biopsy and pathologic grade tumors (P <.001). On multivariate analysis, BMI > or = 35 kg/m(2) was associated with a trend for higher rates of positive surgical margins (P =.008). Overweight patients (BMI, 25 to 30 kg/m(2)) had a significantly decreased risk of seminal vesicle invasion (P =.039). After controlling for all preoperative clinical variables including year of surgery, BMI > or = 35 kg/m(2) significantly predicted biochemical failure after RP (P =.002). After controlling for surgical margin status, BMI > or = 35 kg/m(2) remained a significant predictor of biochemical failure (P =.012). There was a trend for BMI > or = 35 kg/m(2) to be associated with higher failure rates than BMI between 30 and 35 kg/m(2) (P =.053).

CONCLUSION

The percentage of obese men undergoing RP in our data set doubled in the last 10 years. Obesity was associated with higher-grade tumors, a trend toward increased risk of positive surgical margins, and higher biochemical failure rates among men treated with RP. A BMI > or = 35 kg/m(2) was associated with a higher risk of failure than a BMI between 30 and 35 kg/m(2).

Predictors of prostate-specific antigen progression among men with seminal vesicle invasion at the time of radical prostatectomy

BACKGROUND

Seminal vesicle (SV) invasion at the time of radical prostatectomy (RP) generally is considered to be indicative of poor outcome. The authors examined whether there was a subset of men with SV invasion who had long-term prostate-specific antigen (PSA) progression-free survival.

METHODS

Data were examined from 1687 men who underwent RP between 1988 and 2002 at 5 equal-access medical centers. Patients were grouped based on the presence or absence of SV invasion at the time of RP. Clinical and pathologic variables as well as biochemical outcome data were compared across the groups using rank-sum, chi-square, and log-rank tests. Multivariate Cox proportional hazards analysis was used to determine the significant predictors of time to PSA failure among men with SV invasion.

RESULTS

Men with SV invasion had significantly higher PSA values, higher clinical stage, higher grade tumors, and were more likely to have concomitant extracapsular extension or a positive surgical margin. The 5-year PSA progression-free rates for men who had SV invasion was 36%, compared with 70% among men who had no SV invasion. Among men who had SV invasion, using multivariate analysis, only age (P = 0.023), pathologic Gleason score (P = 0.041), and surgical margin status (P = 0.019) were found to be independent predictors of PSA failure. By combining significant prognostic variables, the authors identified a subset of men with SV invasion, low-grade tumors (Gleason score 2-6), and negative surgical margins who had a 5-year PSA progression-free rate of 69%. Men with SV invasion, Gleason scores 2-6 tumors, negative surgical margins, and age > or = 60 years (n = 11; 8%) had a 5-year PSA progression-free rate of 100%.

CONCLUSIONS

Although the majority of men with SV invasion have high-grade disease and a short time to biochemical failure, the authors identified a subset of men with low-grade disease, negative surgical margins, and older age who, despite SV invasion, had an extremely favorable clinical course. Thus, SV invasion does not uniformly suggest an unfavorable prognosis. prognosis.

The percentage of prostate needle biopsy cores with carcinoma from the more involved side of the biopsy as a predictor of prostate specific antigen recurrence after radical prostatectomy

BACKGROUND

The authors previously found that, although the total percentage of prostate needle biopsy cores with carcinoma was a significant predictor of prostate specific antigen (PSA) failure among men undergoing radical prostatectomy (RP), there was a trend toward a lower risk of recurrence in patients with positive bilateral biopsies, suggesting that high-volume, unilateral disease was a worse predictor of outcome than an equivalent number of positive cores distributed over two lobes. In the current study, the authors sought to compare the total percentage of cores with carcinoma directly with the percentage of cores from the more involved or dominant side of the prostate with carcinoma for their ability to predict outcome among men who underwent RP.

METHODS

A retrospective survey of 535 patients from the Shared Equal Access Regional Cancer Hospital database who underwent RP at 4 different equal-access medical centers between 1988 and 2002 was undertaken. The total percentage of cores positive was compared with the percentage of cores positive from the dominant and nondominant sides for their ability to predict biochemical recurrence after RP. The best predictor then was compared with the standard clinical variables PSA, biopsy Gleason score, and clinical stage in terms of ability to predict time to PSA recurrence after RP using multivariate analysis.

RESULTS

The adverse pathologic features of positive surgical margins and extracapsular extension were significantly more likely to be ipsilateral to the dominant side on the prostate biopsy. The percentage of cores positive from the dominant side provided slightly better prediction (concordance index [C] = 0.636) for PSA failure than the total percentage of cores positive (C = 0.596) and markedly better than the percentage of cores from the nondominant side (C = 0.509). Cutoff points for percentage of cores positive from the dominant side were identified (< 34%, 34-67%, and > 67%) that provided significant risk stratification for PSA failure (P < 0.001). On multivariate analysis, the percentage of cores positive from the dominant side was the strongest independent predictor of PSA recurrence (P < 0.001). Biopsy Gleason score (P = 0.017) also was a significant, independent predictor of recurrence. There was a trend, which did not reach statistical significance, toward an association between greater PSA values and biochemical failure (P = 0.052). Combining the PSA level, biopsy Gleason score, and percentage of cores positive from the dominant side of the prostate resulted in a model that provided a high degree of prediction for PSA failure (C = 0.671).

CONCLUSIONS

The percentage of cores positive from the dominant side of the prostate was a slightly better predictor of PSA recurrence than was the total percentage of cores positive. Using the percentage of cores from the dominant side along with the PSA level and the biopsy Gleason score provided significant risk stratification for PSA failure.

One 10-core prostate biopsy is superior to two sets of sextant prostate biopsies

OBJECTIVES

To compare the efficiency of different transrectal ultrasonography (TRUS)-guided prostate biopsy techniques for detecting prostate cancer.

MATERIALS AND METHODS

In all, 81 prostates from radical prostatectomy were used and two consecutive sets of sextant biopsies and one 10-core biopsy taken in each specimen. The 10-core biopsy consisted of a sextant biopsy and four cores from the far lateral areas of the prostate. To simulate a transrectal biopsy procedure, all biopsies were taken under TRUS guidance.

RESULTS

In the first set of sextant biopsies 44 prostate cancers (54%) were detected and in the second set 51 (63%). Combining both sets of sextant biopsies 57 (70%) of the carcinomas were detected. One set of 10-core biopsies detected 66 (82%) of all prostate cancers. Overall, with the 10-core biopsies 16% more prostate tumours were diagnosed than with two consecutive sets of sextant biopsies. To find the same number of prostate cancers as with the 10-core technique, 14% of patients undergoing sextant biopsy would require a second set and 11% at least a third set of biopsies.

CONCLUSIONS

The 10-core prostate biopsy technique is superior to the commonly used sextant technique and could spare patients unnecessary repeated biopsy. Even after including a second set of sextant biopsies, the total detection rate with these 12 biopsies was inferior to the 10-core technique.

Percent of prostate needle biopsy cores with cancer is significant independent predictor of prostate specific antigen recurrence following radical prostatectomy: results from SEARCH database

PURPOSE

Recent studies have suggested that the percent of positive cores in the prostate needle biopsy is a significant predictor of outcome among men undergoing radical prostatectomy or radiation therapy for prostate cancer. We evaluate whether either percent of cores with cancer or percent of cores positive from the most and least involved side of the prostate needle biopsy was associated with a worse outcome among men treated with radical prostatectomy.

MATERIALS AND METHODS

A retrospective survey of 1,094 patients from the SEARCH Database treated with radical prostatectomy at 4 different equal access medical centers in California between 1988 and 2002 was undertaken. We used multivariate analysis to examine whether total percent of prostate needle biopsy cores with cancer, percent of cores positive from each side of the prostate and other clinical variables were significant predictors of adverse pathology and time to prostate specific antigen (PSA) recurrence following radical prostatectomy.

RESULTS

On multivariate analysis serum PSA and percent of positive cores were significant predictors of positive surgical margins, nonorgan confined disease and seminal vesicle invasion. Percent of positive cores (p <0.001), serum PSA (p = 0.008) and biopsy Gleason score (p = 0.014) were significant independent predictors of time to biochemical recurrence. On a separate multivariate analysis that included the variables of total percent of positive cores, percent of positive cores from the most involved side of the biopsy, percent of positive cores from the least involved side of the biopsy and whether the biopsy was positive unilaterally or bilaterally, only the percent of positive cores from the most involved side of the biopsy was a significant independent predictor of PSA failure following radical prostatectomy. Percent of positive cores was used to separate patients into a low risk (less than 34%), intermediate risk (34% to 50%) and high risk (greater than 50%) groups, which provided significant preoperative risk stratification for PSA recurrence following radical prostatectomy (p <0.001). Percent of positive cores cut points were able to further risk stratify men who were at low (p = 0.001) or intermediate (p = 0.036) but not high (p = 0.674) risk for biochemical failure based on serum PSA and biopsy Gleason score.

CONCLUSIONS

Percent of positive cores in the prostate needle biopsy was a significant predictor of adverse pathology and biochemical failure following radical prostatectomy, and the cut points of less than 34%, 34% to 50% and greater than 50% can be used to risk stratify patients preoperatively. The finding that percent of positive cores from the most involved side of the biopsy was a stronger predictor of PSA failure than the total percent of cores involved suggests that multiple positive biopsies from a single side might be a better predictor of a larger total cancer volume and thus correlate with clinical outcome.

Should a positive surgical margin following radical prostatectomy be pathological stage T2 or T3? Results from the SEARCH database

PURPOSE

The finding of a positive surgical margin associated with extracapsular extension at radical prostatectomy is a poor prognostic factor. However, whether a positive surgical margin with no documented extracapsular extension portends a similarly poor prognosis is unclear. We examined the significance of the pathological features of positive surgical margin and extracapsular extension for predicting biochemical failure following radical prostatectomy.

MATERIALS AND METHODS

We examined data on 1,621 men from the SEARCH Database of patients treated with radical prostatectomy without lymph node metastasis. Patients were separated into 5 groups based on the pathological findings of positive surgical margin, extracapsular extension, and/or seminal vesicle invasion. Preoperative clinical variables were compared across the groups and the groups were compared for time to biochemical recurrence using Cox proportional hazards analysis.

RESULTS

Men with seminal vesicle invasion had the highest prostate specific antigen (PSA) recurrence rates, while men with a negative surgical margin and no extracapsular extension had the lowest PSA recurrence rates. There were no differences in PSA failure rates between men with a positive surgical margin and no extracapsular extension versus men with a negative surgical margin and extracapsular extension versus men with extracapsular extension and a positive surgical margin. In this subset of patients with a positive surgical margin and/or extracapsular extension but no seminal vesicle invasion only serum PSA was a significant independent predictor of biochemical recurrence.

CONCLUSIONS

Men with a positive surgical margin but no extracapsular extension had PSA recurrence rates similar to those in men with extracapsular extension with or without positive margins. Men with extracapsular extension had similar biochemical recurrence rates whether the surgical margin was positive or negative. If confirmed at other institutions, consideration should be given to modifying the current TNM staging system to reflect these findings.

Time trends in biochemical recurrence after radical prostatectomy: results of the SEARCH database

OBJECTIVES

To determine whether in the prostate-specific antigen (PSA) era stage and/or grade migration of patients treated with radical prostatectomy (RP) has occurred. We also examined whether the biochemical recurrence rates after RP have changed with time.

METHODS

A total of 1654 patients from the Shared Equal Access Regional Cancer Hospital (SEARCH) database were analyzed for time trends in age, preoperative PSA level, clinical stage, biopsy Gleason score, prostatectomy Gleason grade, pathologic stage, margin status, and recurrence rates after RP. Results were stratified into three 4-year blocks of time between 1988 and 2002 for analysis.

RESULTS

The preoperative PSA level, patient age, tumor stage, rate of capsular penetration, and lymph node involvement decreased with time. Both biopsy and pathologic Gleason grade steadily increased with time. The positive margin rate and incidence of seminal vesicle involvement remained stable. On multivariate analysis, only serum PSA level (P <0.001) and biopsy Gleason score (P <0.001) were significant independent predictors of the time to recurrence after RP. The year of surgery was not a significant independent predictor of biochemical recurrence after RP in multivariate analysis.

CONCLUSIONS

Despite lower stage and lower PSA levels with time, we found no improvement in PSA recurrence rates over time. This may reflect lead-time bias in detecting PSA recurrence by the use of more sensitive PSA assays in recent years.