Transperineal extended biopsy improves the clinically significant prostate cancer detection rate: A comparative study of 6 and 12 biopsy cores

Shifting to transperineal prostate biopsy: A narrative review

To address the limitations and challenges associated with transrectal (TR) biopsy and to present transperineal (TP) biopsy as a viable and potentially safer alternative to TR biopsy. Prostate cancer (PCa) is a significant global health concern. The prevalence of advanced-stage prostate cancer in Asia is higher than that in the United States, emphasizing the need for effective screening and diagnosis methods. The gold standard of diagnosis is a TR biopsy. However, it has limitations due to the risk of infection and potential complications, such as injury to the rectal artery. Efforts have been made to address issues such as false-negative biopsies, under-sampling, and over-sampling through MRI-guided biopsies. However, the TR approach makes it difficult to access the apical and anterior regions of the prostate. TP biopsy has emerged as an alternative to address the limitations of TR biopsy. Nevertheless, a TP biopsy is a painful procedure, requiring the use of general anesthesia and expensive equipment. As a result, it has been perceived as costly and time-consuming. In addition, it requires a steep learning curve. The introduction of local anesthesia such as pudendal nerve block and the adoption of freehand techniques have contributed to the feasibility of performing TP biopsy. Recent research indicates that freehand TP biopsy can yield comparable diagnostic results to template-guided approaches. The diagnostic performance, cancer detection rates, and complication rates of TP biopsy have demonstrated its potential as a safe and effective diagnostic method.

Sextant Systematic Biopsy Versus Extended 12-Core Systematic Biopsy in Combined Biopsy for Prostate Cancer

BACKGROUND

This study assessed the comparative effectiveness of sextant and extended 12-core systematic biopsy within combined biopsy for the detection of prostate cancer.

METHODS

Patients who underwent combined biopsy targeting lesions with a Prostate Imaging Reporting and Data System (PI-RADS) score of 3-5 were assessed. Two specialists performed all combined cognitive biopsies. Both specialists performed target biopsies with five or more cores. One performed sextant systematic biopsies, and the other performed extended 12-core systematic biopsies. A total of 550 patients were analyzed.

RESULTS

Cases requiring systematic biopsy in combined biopsy exhibited a significant association with age ≥ 65 years (odds ratio [OR], 2.32; 95% confidence interval [CI], 1.25-4.32; P = 0.008), PI-RADS score (OR, 2.32; 95% CI, 1.25-4.32; P = 0.008), and the number of systematic biopsy cores (OR, 3.69; 95% CI, 2.11-6.44; P < 0.001). In patients with an index lesion of PI-RADS 4, an extended 12-core systematic biopsy was required (target-negative/systematic-positive or a greater Gleason score in the systematic biopsy than in the targeted biopsy) (P < 0.001).

CONCLUSION

During combined biopsy for prostate cancer in patients with PI-RADS 3 or 5, sextant systematic biopsy should be recommended over extended 12-core systematic biopsy when an effective targeted biopsy is performed.

Initial Outcomes of Freehand Transperineal Biopsies Regarding Diagnostic Value and Safety: An Early Experience at King Fahad Specialist Hospital, Buraydah, Saudi Arabia

BACKGROUND

Prostate cancer is a common type of cancer in Saudi Arabia with a high incidence rate. Trans-rectal ultrasound guided prostatic biopsy (TRUSBx) has been the standard diagnostic study for prostate cancer since a landmark study in 1989 which showed that it is better than digitally directed biopsy sampling of the prostate. As an alternative to TRUSBx, transperineal biopsies (TPBx) have gained popularity as they give a higher accuracy rate and avoid many complications. A new study has been conducted in Riyadh, Saudi Arabia to compare TRUSBx and TPBx showed that TPBx has a significantly higher detection rate of prostate cancer cases compared to TRUSBx (45.1% vs. 29.1%, p=0.003). The aim of this study is to determine the diagnostic value and safety of freehand transperineal prostate biopsy in patients with an elevated prostatic specific antigen (PSA) and/or abnormal digital rectal exam in King Fahad Specialist Hospital KFSH in Buraydah, Qassim region, Saudi Arabia.

METHODS

This is an observational retrospective study of all patients (n=39) who underwent transperineal biopsies at KFSH to assess the diagnostic value and safety of the procedure.

RESULTS

The mean age of the patients was 70.3 (SD 10.1) years. The most commonly found diagnosis was adenocarcinoma (61.5%), and incidence of complications was detected in (5.1%) of the patients.

CONCLUSION

We concluded that the freehand technique TPBx has a high accuracy rate in detecting prostatic cancer. However, the learning curve could be a limiting factor in implementing it. Increasing the number of biopsies could positively affect diagnostic accuracy, especially with our low complication rate in this procedure. A low number of biopsies in the older age group can give an accurate result with a low risk of complications. Although template-guided TPBx and robot-guided TPBx are better options, the freehand technique represents a cost-effective and time-saving alternative. However, more studies are needed to compare the outcome of such a technique.

Comparison of cancer detection rates by transrectal prostate biopsy for prostate cancer using two different nomograms based on patient's age and prostate volume

Background

The aim of this study is to evaluate the efficacy of two different Nara Urological Research and Treatment Group (NURTG) nomograms allocating 6–12 biopsy cores based on age and prostate volume.

Materials and methods

From April 2006 to July 2014, a total of 1,605 patients who underwent initial prostate biopsy were enrolled. Based on a nomogram taking the patient’s age and prostate volume into consideration, 6–12 biopsy cores were allocated. Two types of nomogram were used, for the former group (before March 2009) and latter group (March 2009 onward). Cancer detection rates in all patients and those with prostate-specific antigen values in the gray zone (4.0–10 ng/mL) were compared. Predictive parameters for detection of prostate cancer in gray-zone patients were also investigated.

Results

The cancer detection rates in all patients and those in the gray zone were 48% and 38% in the former group and 54% and 41% in the latter group, respectively. The cancer detection rate in all patients was significantly higher in the latter group compared with the former group, but detection in gray-zone patients did not show a significant difference between the two groups (P=0.011 and P=0.37, respectively). Multivariate analysis indicated that age, digital rectal examination, prostate volume, transrectal ultrasonography findings, and volume/biopsy ratio were significant predictive parameters in gray-zone patients. The clinically insignificant cancer detection rate was significantly lower in the latter group compared with the former group (P=0.0008).

Conclusion

The latter nomogram provided more acceptable detection rates of clinically significant and insignificant cancer than the former one, and we consider that an initial maximum 12-core transrectal ultrasound-guided needle biopsy may be sufficient for prostate cancer diagnosis.

Active surveillance for prostate cancer

It is worth distinguishing between the two strategies of expectant management for prostate cancer. Watchful waiting entails administering non-curative androgen deprivation therapy to patients on development of symptomatic progression, whereas active surveillance entails delivering curative treatment on signs of disease progression. The objectives of the two management strategies and the patients enrolled in either are different: (i) to review the role of active surveillance as a management strategy for patients with low-risk prostate cancer; and (ii) review the benefits and pitfalls of active surveillance. We carried out a systematic review of active surveillance for prostate cancer in the literature using the National Center for Biotechnology Information's electronic database, PubMed. We carried out a search in English using the terms: active surveillance, prostate cancer, watchful waiting and conservative management. Selected studies were required to have a comprehensive description of the demographic and disease characteristics of the patients at the time of diagnosis, inclusion criteria for surveillance, and a protocol for the patients' follow up. Review articles were included, but not multiple papers from the same datasets. Active surveillance appears to reduce overtreatment in patients with low-risk prostate cancer without compromising cancer-specific survival at 10 years. Therefore, active surveillance is an option for select patients who want to avoid the side-effects inherent to the different types of immediate treatment. However, inclusion criteria for active surveillance and the most appropriate method of monitoring patients on active surveillance have not yet been standardized.

The optimal number of initial prostate biopsy cores in daily practice: a prospective study using the Nara Urological Research and Treatment Group nomogram

Background

To elucidate the optimal number of prostate biopsy cores using a nomogram allocating 6–12 biopsy cores, the number generally used in daily practice, based on age and prostate volume (PV).

Methods

We enrolled 936 patients who received an initial prostate biopsy from April 2006 to January 2009. A number of 6–12 biopsy cores was allocated based on age and PV Nara Urological Research and Treatment Group (NURTG) nomogram. To elucidate the predictive parameters of cancer detection in patients with a prostate specific antigen (PSA) value in the gray zone, univariate and multivariate logistic regression analysis were carried out.

Results

The total cancer detection rate and the cancer detection rate in the PSA gray zone (4.1–10.0 ng/mL) were 48.0 and 37.6 %, respectively. The cancer detection rates in the gray zone stratified by patient age of ≤59, 60–64, 65–69, 70–74, 75–79, and ≥80 years were 28.4, 35.0, 26.9, 37.9, 45.7, and 54.8 %, respectively. The significant predictive parameters of cancer detection in the gray zone were age, volume biopsy ratio (VBR: PV divided by number of biopsy cores), PSA density (PSAD), digital rectal examination findings, and transrectal ultrasound findings in univariate analyses. Finally, age, VBR, and PSAD were independent parameters to predict cancer detection in the gray zone. The adverse event profile was acceptable.

Conclusions

Our present study revealed that the cancer detection rate using the NURTG nomogram allocating 6–12 biopsy cores, the number generally used in daily practice, based on age and PV, could provide similar efficacy as previous studies involving more biopsy cores. In older patients the number of biopsy cores could be reduced.

Role of transperineal template biopsy in prostate cancer

Prostate cancer is the most common neoplasm diagnosed in men. Whilst treatment modalities have progressed, diagnostic investigations in terms of biopsy methods have been assessed but there is no consensus of when the different diagnostic methods in terms of transrectal ultrasound (TRUS) or transperineal template (TPT) should be utilised. TPT biopsy has a higher diagnostic yield than TRUS in those with a primary biopsy, in those with previous negative biopsies with TRUS as well as those undergoing saturation biopsies. Despite the increased likelihood of diagnosing cancer with TPT than TRUS this maybe secondary to the increased number of biopsies being utilised. However there is no consensus regarding the ideal number of biopsies that should be utilised with TPT. Furthermore it is felt that the increased number of biopsies utilised with TPT is associated the higher complication rates with TPT. The role of TPT biopsy is recognised in those with previous negative biopsies with transrectal ultrasound but further work is required regarding the ideal number of biopsies. Furthermore, it is felt that TPT biopsy may have a role in primary biopsy.

Analysis of prostate cancer localization toward improved diagnostic accuracy of transperineal prostate biopsy

PURPOSE

Delineating the precise localization of prostate cancer is important in improving the diagnostic accuracy of prostate biopsy.

METHODS

In Juntendo University Nerima Hospital, initial 12-core or repeat 16-core biopsies were performed using a transrectal ultrasound guided transperineal prostate biopsy method. We step-sectioned prostates from radical prostatectomy specimens at 5-mm intervals from the urethra to the urinary bladder and designated five regions: the (1) Apex, (2) Apex-Mid, (3) Mid, (4) Mid-Base, and (5) Base. We then mapped prostate cancer localization on eight zones around the urethra for each of those regions.

RESULTS

Prostate cancer was detected in 93 cases of 121 cases (76.9%) in the Apex, in 115 cases (95.0%) in the Apex-Mid, in 101 cases (83.5%) in the Mid, in 71 cases (58.7%) in the Mid-Base, and in 23 cases (19.0%) in the Base. In 99.2% of all cases, prostate cancers were detected from the Apex to Mid regions. For this reason, transperineal prostate biopsies have routinely been prioritized in the Apex, Apex-Mid, and Mid regions, while the Base region of the prostate was considered to be of lesser importance. Our analyses of prostate cancer localization revealed a higher rate of cancer in the posterior portion of the Apex, antero-medial and postero-medial portion of the Apex-Mid and antero-medial and postero-lateral portion of the Mid. The transperineal prostate biopsies in our institute performed had a sensitivity of 70.9%, a specificity of 96.6%, a positive predictive value (PPV) of 92.2% and a negative predictive value (NPV) of 85.5%.

CONCLUSIONS

The concordance of prostate cancer between prostatectomy specimens and biopsies is comparatively favorable. According to our study, the diagnostic accuracy of transperineal prostate biopsy can be improved in our institute by including the anterior portion of the Apex-Mid and Mid regions in the 12-core biopsy or 16-core biopsy, such that a 4-core biopsy of the anterior portion is included.

High b value (2,000 s/mm2) diffusion-weighted magnetic resonance imaging in prostate cancer at 3 Tesla: comparison with 1,000 s/mm2 for tumor conspicuity and discrimination of aggressiveness

Objective

The objective of our study was to investigate tumor conspicuity and the discrimination potential for tumor aggressiveness on diffusion-weighted magnetic resonance imaging (DW-MRI) with high b value at 3-T.

Materials and Methods

The institutional review board approved this study and waived the requirement for informed consent. A total of 50 patients with prostate cancer (69 cancer foci; 48 in the PZ, 20 in the TZ, and one in whole prostate) who underwent multiparametric prostate MRI including DW-MRI (b values: 0, 1000 s/mm² and 0, 2000 s/mm²) on a 3-T system were included. Lesion conspicuity score (LCS) using visual assessment (1 = invisible for surrounding normal site; 2 = slightly high intensity; 3 = moderately high; and 4 = very high) and tumor-normal signal intensity ratio (TNR) were assessed, and apparent diffusion coefficient (ADC, ×10⁻³ mm²/s) of the tumor regions and normal regions were measured.

Results

Mean LCS and TNR at 0, 2000 s/mm² was significantly higher than those at 0, 1000 s/mm² (p<0.001 for both). In addition, ADC at both 0, 1000 and 0, 2000 s/mm² was found to distinguish intermediate or high risk cancer with Gleason score ≥7 from low risk cancer with Gleason score ≤6 (p<0.001 for both). Furthermore, ADC of tumor regions correlated with Gleason score at both 0, 1000 s/mm² (ρ = −0.602; p<0.001) and 0, 2000 s/mm² (ρ = −0.645; p<0.001).

Conclusions

For tumor conspicuity and characterization of prostate cancer on DW-MRI of 3-T MRI, b = 0, 2000 s/mm² is more useful than b = 0, 1000 s/mm².

Transperineal ultrasound-guided 12-core prostate biopsy: an extended approach to diagnose transition zone prostate tumors

Objective

Transperineal ultrasound-guided (TPUS) 12-core prostate biopsy was evaluated as an initial strategy for the diagnosis of prostate cancer, The distribution of prostate cancer lesions was assessed with zone-specific biopsy.

Methods

From January 2010 to December 2012, 287 patients underwent TPUS-guided 12-core prostate biopsy. Multiple cores were obtained from both the peripheral zone (PZ) and the transition zone (TZ) of the prostate. Participants' clinical data and the diagnostic yield of the cores were recorded and prospectively analyzed as a cross-sectional study.

Results

The diagnostic yield of the 12-core prostate biopsy was significantly higher compared to the 6-core scheme (42.16 vs. 21.6%). The diagnostic yield of the 10-core prostate biopsy was significantly higher compared to the 6-core scheme (37.6 vs. 21.6%). The 12-core scheme improved the diagnostic yield in prostates >50 ml (12-core scheme: 28.1% vs. 10-core scheme: 20.4%; p = 0.034).

Conclusions

The 12-core biopsy scheme is a safe and effective approach for the diagnosis of prostate cancer. TZ biopsies in patients with larger prostates should be included in the initial biopsy strategy.

Transperineal biopsy of the prostate--is this the future? Nat Rev Urol. 2013;10:690-702. [PMID: 24061531 DOI: 10.1038/nrurol.2013.195]

Transperineal prostate biopsy is re-emerging after decades of being an underused alternative to transrectal biopsy guided by transrectal ultrasonography (TRUS). Factors driving this change include possible improved cancer detection rates, improved sampling of the anteroapical regions of the prostate, a reduced risk of false negative results and a reduced risk of underestimating disease volume and grade. The increasing incidence of antimicrobial resistance and patients with diabetes mellitus who are at high risk of sepsis also favours transperineal biopsy as a sterile alternative to standard TRUS-guided biopsy. Factors limiting its use include increased time, training and financial constraints as well as the need for high-grade anaesthesia. Furthermore, the necessary equipment for transperineal biopsy is not widely available. However, the expansion of transperineal biopsy has been propagated by the increase in multiparametric MRI-guided biopsies, which often use the transperineal approach. Used with MRI imaging, transperineal biopsy has led to improvements in cancer detection rates, more-accurate grading of cancer severity and reduced risk of diagnosing clinically insignificant disease. Targeted biopsy under MRI guidance can reduce the number of cores required, reducing the risk of complications from needle biopsy.

Prostate saturation biopsy following a first negative biopsy: state of the art

INTRODUCTION

Saturation prostate biopsy (SPBx) has been initially introduced to improve prostate cancer (PCa) detection rate (DR) in the repeat setting. Nevertheless, the optimal number and the most appropriate location of the cores, together with the timing to perform a second PBx and the eventual modification of the PBx protocols according to the different clinical situations, are matters of debate. The aim of this review is to perform a critical analysis of the literature about the actual role of SPBx in the repeat setting.

MATERIALS AND METHODS

We performed a systematic review of the literature since 1995 up to 2011. Electronic searches were limited to the English language, using the MEDLINE database. The key words 'saturation prostate biopsy' and 'repeated prostate biopsy' were used.

RESULTS

SPBx improves PCa DR if clinical suspicion persists after previous biopsy with negative findings and provides an accurate prediction of prostate tumor volume and grade, even if the issue about the number and locations of the cores is still a matter of debate.

CONCLUSIONS

At present, SPBx seems to be really necessary in men with persistent suspicion of PCa after negative initial biopsy and probably in patients with a multifocal high-grade prostatic intraepithelial neoplasia or atypical small acinar proliferation. In the remaining situations, adopting an individualized scheme is preferable.

Evaluating the Prostate Cancer Prevention Trial High Grade Prostate Cancer Risk Calculator in 10 international biopsy cohorts: results from the Prostate Biopsy Collaborative Group

OBJECTIVES

To assess the applicability of the Prostate Cancer Prevention Trial High Grade (Gleason grade ≥ 7) Risk Calculator (PCPTHG) in ten international cohorts, representing a range of populations.

METHODS

A total of 25,512 biopsies from 10 cohorts (6 European, 1 UK and 3 US) were included; 4 implemented 6-core biopsies, and the remaining had 10 or higher schemes; 8 were screening cohorts, and 2 were clinical. PCPTHG risks were calculated using prostate-specific antigen, digital rectal examination, age, African origin and history of prior biopsy and evaluated in terms of calibration plots, areas underneath the receiver operating characteristic curve (AUC) and net benefit curves.

RESULTS

The median AUC of the PCPTHG for high-grade disease detection in the 10- and higher-core cohorts was 73.5% (range, 63.9-76.7%) compared with a median of 78.1% (range, 72.0-87.6%) among the four 6-core cohorts. Only the 10-core Cleveland Clinic cohort showed clear evidence of under-prediction by the PCPTHG, and this was restricted to risk ranges less than 15%. The PCPTHG demonstrated higher clinical net benefit in higher-core compared with 6-core biopsy cohorts, and among the former, there were no notable differences observed between clinical and screening cohorts, nor between European and US cohorts.

CONCLUSIONS

The PCPTHG requires minimal patient information and can be applied across a range of populations. PCPTHG risk thresholds ranging from 5 to 20%, depending on patient risk averseness, are recommended for clinical prostate biopsy decision-making.

Prostate cancer detection in patients with total serum prostate-specific antigen levels of 4-10 ng/mL: diagnostic efficacy of diffusion-weighted imaging, dynamic contrast-enhanced MRI, and T2-weighted imaging

OBJECTIVE

The purpose of this study is to evaluate the utility of T2-weighted imaging, dynamic contrast-enhanced MRI (DCE-MRI), and diffusion-weighted imaging (DWI) for detecting prostate cancer in patients with total serum prostate-specific antigen (PSA) levels of 4-10 ng/mL, which is referred to as the "gray zone."

MATERIALS AND METHODS

Fifty patients with gray-zone PSA levels underwent MRI before biopsy. According to the sites of biopsy, the prostate was divided into eight regions on MRI scans. These regions were evaluated individually for the following features: detectability of prostate cancer on per-region and per-patient bases, and relationship between tumor size and positive or negative MRI findings for tumor detection.

RESULTS

On a per-region basis, the sensitivity and specificity of tumor detection were 36% and 97% for T2-weighted imaging, 43% and 95% for DCE-MRI, 38% and 96% for DWI, and 53% and 93% for the combined method of MRI, respectively. The sensitivity of combined MRI to detect tumor was significantly higher than those of the individual methods (p < 0.001 to p = 0.001). Tumor size was significantly larger in regions with positive MRI findings than in regions with negative MRI findings (p = 0.004). On a per-patient basis, sensitivity and specificity of combined MRI to detect prostate cancer were 83% and 80%, respectively.

CONCLUSION

Combined T2-weighted imaging, DWI, and DCE-MRI findings appear to be potentially useful for detecting and managing prostate cancer, even when performed for patients with gray-zone PSA levels.

Beyond diagnosis: evolving prostate biopsy in the era of focal therapy

Despite decades of use as the “gold standard” in the detection of prostate cancer, the optimal biopsy regimen is still not universally agreed upon. While important aspects such as the need for laterally placed biopsies and the importance of apical cancer are known, repeated studies have shown significant patients with cancer on subsequent biopsy when the original biopsy was negative and an ongoing suspicion of cancer remained. Attempts to maximise the effectiveness of repeat biopsies have given rise to the alternate approaches of saturation biopsy and the transperineal approach. Recent interest in focal treatment of prostate cancer has further highlighted the need for accurate detection of prostate cancer, and in response, the introduction of transperineal template-guided biopsy. While the saturation biopsy approach and the transperineal template approach increase the detection rate of cancer in men with a previous negative biopsy and appear to have acceptable morbidity, there is a lack of clinical trials evaluating the different biopsy strategies. This paper reviews the evolution of prostatic biopsy and current controversies.

Optimizing performance and interpretation of prostate biopsy: a critical analysis of the literature

CONTEXT

The number and location of biopsy cores and the interpretation of prostate biopsy in different clinical settings remain the subjects of continuing debate.

OBJECTIVE

Our aim was to review the current evidence regarding the performance and interpretation of initial, repeat, and saturation prostatic biopsy.

EVIDENCE ACQUISITION

A comprehensive Medline search was performed using the Medical Subject Heading search terms prostate biopsy, prostate cancer, detection, transrectal ultrasound (TRUS), nomogram, and diagnosis. Results were restricted to the English language, with preference given to those published within the last 3 yr.

EVIDENCE SYNTHESIS

At initial biopsy, a minimum of 10 but not >18 systematic cores are recommended, with 14-18 cores in glands ≥ 50 cm³. Biopsies should be directed laterally, and transition zone (TZ) cores are not recommended in the initial biopsy setting. Further biopsy sets, either as an extended repeat or as a saturation biopsy (≥ 20 cores) including the TZ, are warranted in young and fit men with a persistent suspicion of prostate cancer. An immediate repeat biopsy is not indicated for prior high-grade prostatic intraepithelial neoplasia diagnosis given an adequate extended initial biopsy. Conversely, biopsies with atypical glands that are suspicious but not diagnostic of cancer should be repeated within 3-6 mo. Overall recommendations for further biopsy sets (a third set or more) cannot be made. Transrectal ultrasound-guided systematic biopsies represent the standard-of-care method of prostate sampling. However, transperineal biopsies are an up-to-standard alternative.

CONCLUSIONS

The optimal prostatic biopsy regimen should be based on the individualized clinical setting of the patient and should follow the minimum standard requirements reported in this paper.

Caudal analgesia for prostate biopsy

BACKGROUND

Although various local anesthesia techniques have been suggested to decrease pain and discomfort during a transrectal ultrasound (TRUS)-guided prostate biopsy, the best method has not yet been defined. The present prospective, double-blind, randomized study aims to investigate the clinical efficacy of 'walking' caudal block compared with an intrarectal lidocaine gel for this procedure.

METHODS

One hundred patients were randomly assigned to two groups. In the lidocaine gel group, 10 ml of gel containing 2% lidocaine was given intrarectally. In the caudal group, 20 ml 0.1% bupivacaine with 75 microg fentanyl was injected. Pain scores, anal sphincter tone and patient satisfaction were evaluated.

RESULTS

The pain scores were significantly lower in the caudal group at all stages. Verbal rating scores (scale 1-4) during probe insertion, probe maneuver and biopsies were 1 (0-2), 1 (0-2) and 1 (0-2) vs. 3 (0-5), 2 (1-3) and 4 (2-6), respectively (P value <0.0001 at all stages). The anal sphincter was more relaxed in the caudal group than in the gel group (P value <0.0001 in all categories). Highly satisfied patients were more frequently encountered in the caudal group, 34 (68%) vs. 8 (16%), P<0.0001, and unsatisfied patients were more frequently found in the gel group 1 (2%) vs. 12 (24%); P<0.001. All patients were able to walk without any assistance immediately after the procedures.

CONCLUSION

'Walking' caudal analgesia is an efficacious method for relieving the pain during TRUS-guided prostate biopsies in ambulatory practice.

Prostate cancer: relationships between postbiopsy hemorrhage and tumor detectability at MR diagnosis

PURPOSE

To retrospectively evaluate the influence of postbiopsy hemorrhage on the accuracy of tumor detection at T2-weighted magnetic resonance (MR) imaging, dynamic contrast material-enhanced MR imaging, and diffusion-weighted (DW) MR imaging of prostate cancer, with histologic findings as the reference standard.

MATERIALS AND METHODS

The institutional review board approved this study and waived the requirement for informed consent. Forty male patients aged 62-84 years (mean age, 71 years) who had prostate cancer underwent MR imaging of the prostate gland after ultrasonographically (US) guided systematic 12-core-specimen biopsy. The mean time between biopsy and MR imaging was 24 days (range, 6-54 days). T1-weighted, T2-weighted, dynamic contrast-enhanced, and DW imaging examinations were performed at 1.5 T. The prostate was divided, according to the biopsy sites, into eight regions on the MR images. Three reviewers in consensus evaluated each region for hemorrhage and prostate cancer. Statistical evaluations were performed with Mann-Whitney U, Ryan, and Spearman rank correlation tests.

RESULTS

Intraglandular hemorrhage was observed in 38 (95%) patients and significantly more often in the peripheral zone (PZ) than in the transition zone (TZ) (P < .001). Degree of hemorrhage did not correlate significantly (P = .536) with time between biopsy and MR imaging. The sensitivity, specificity, and accuracy of combined T2-weighted, dynamic contrast-enhanced, and DW imaging in the diagnosis of prostate cancer were 69%, 85%, and 78%, respectively. Sensitivity and specificity were lower for the TZ than for the PZ. Degree of hemorrhage was significantly lower in regions of positive biopsy findings than in regions of negative biopsy findings (P = .001) and correlated negatively with tumor size (P = .043).

CONCLUSION

Interpretation of combined T2-weighted, dynamic contrast-enhanced, and DW MR image findings can yield reasonable diagnostic accuracy in both the PZ (80% [191 of 240 regions]) and the TZ (74% [59 of 80 regions]).

The potential role of prebiopsy magnetic resonance imaging combined with prostate-specific antigen density in the detection of prostate cancer

AIM

Two-thirds of patients with a gray-zone prostate-specific antigen (PSA) level undergo unnecessary biopsy. Sensitivity is not yet sufficient to permit the use of modified PSA parameters or magnetic resonance (MR) imaging alone for prostate cancer screening. Thus, we evaluated the combination of MR imaging and PSA density (PSAD) for specificity and sensitivity.

METHODS

During the period April 2004 through March 2006, 185 patients with a PSA level of 4.0-10.0 ng/mL underwent MR imaging and transrectal ultrasonography-guided 8-core biopsy (systemic sextant biopsy of the peripheral zone plus two cores of transition zone). All MR images were interpreted prospectively by two radiologists. An image was considered positive for prostate cancer if any feature indicated a cancerous lesion. Receiver operating characteristic (ROC) curves were used to compare the usefulness of the PSA level, PSAD and PSA transitional zone density (PSATZ) for the detection of prostate cancer.

RESULTS

Of the 185 patients, 62 had prostate cancer. Sensitivity and specificity of the axial T2-weighted MR imaging findings for cancer detection were 79.0% and 59.4%, respectively. The area under the ROC curve was 0.590 for the PSA level, 0.718 for PSAD and 0.695 for PSATZ. MR imaging findings and PSAD were shown by multivariate analysis to be statistically significant independent predictors of prostate cancer (P < 0.001). With a PSAD cut-off value of 0.111, sensitivity was 96.8%, but specificity was 19.5%. Combining MR imaging findings with PSAD increased the specificity to 40% and retained 95% sensitivity.

CONCLUSION

MR imaging findings combined with PSAD provide high sensitivity and improve the specificity for the early detection of prostate cancer.

Optimal approach for prostate cancer detection as initial biopsy: prospective randomized study comparing transperineal versus transrectal systematic 12-core biopsy

OBJECTIVES

Transperineal and transrectal prostate biopsy are both used for prostate cancer detection. However, which approach is superior remains unknown. In this study, we performed a prospective randomized study to compare the efficacy of transperineal versus transrectal 12-core initial prostate biopsy.

METHODS

From May 2003 to October 2005, a prospective randomized study of transperineal versus transrectal 12-core biopsy (126 and 120 patients, respectively) was conducted in 246 patients with a prostate-specific antigen level of 4.0 to 20.0 ng/mL. All procedures were performed with the patient in the lithotomy position, with the transperineal and transrectal approach performed with spinal anesthesia (0.5% bupivacaine) or a caudal block (1% lidocaine), respectively. With both approaches, eight biopsy specimens were obtained systematically from the peripheral zone, including the apex, and four from the transition zone.

RESULTS

The cancer detection rate was 42.1% (53 of 126 patients) with the transperineal approach and 48.3% (58 of 120 patients) with the transrectal approach (P = 0.323). For all patients undergoing transperineal and transrectal biopsy, the cancer core rate (cancer core number/biopsy core number) was 13.7% (207 of 1512 cores) and 14.4% (208 of 1440 cores), respectively (P = 0.566). Apart from headache, presumably related to the spinal anesthesia, no significant differences were found in the complications between the two groups.

CONCLUSIONS

No significant differences were found in the cancer detection rate, cancer core rate, or complications between the two approaches. We believe that the preferred approach as an initial prostate biopsy is the transrectal approach, which does not require spinal anesthesia or another burdensome process.

[Prostate biopsy strategies. A review of the literature]

INTRODUCTION

In 1987 transrectal ultrasound was described like the technique for guiding prostate biopsy. Since that time different options of transrectal ultrasound guided prostate biopsy were described.

MATERIAL AND METHODS

We did a reviewed of the different techniques and cores distribution in the prostate biopsy, also we describes the patient preparation and the most important complications.

RESULTS

The majority of the reviewed showed an increase in the sensibility rates with the extended transrectal ultrasound guided prostate biopsies. These improvements generally are due to the most lateral zones.

CONCLUSION

Until now, due to a great experience and a low complications rate, the transrectal ultrasound guided prostate biopsy strategy should be extended respect the classical sextant biopsy with cores from the most lateral zones of the prostate.

Direct comparison between transrectal and transperineal extended prostate biopsy for the detection of cancer

AIM

To establish whether extended transrectal (TR) and extended transperineal (TP) biopsies are equivalent in detecting prostate cancer.

METHODS

Due to an elevated prostate-specific antigen (PSA) greater than 2.5 ng/mL or abnormal digital rectal examination findings, 783 men underwent a transrectal ultrasound-guided three-dimensional 26-core biopsy, a combination of TR 12-core and TP 14-core biopsies. Using recursive partitioning, the best combination of sampling sites that gave the highest cancer detection rate at a given number of biopsy cores was selected either with a TR or a TP approach. The cancer detection rate and characteristics of detected cancers were compared between the TP 14-core and the TR 12-core biopsies and between selected subset biopsy schemes.

RESULTS

Prostate cancer was detected in 283 of the 783 men (36%). There was no statistical difference in cancer detection rate or in the characteristics of detected cancers between TP 14-core and TR 12-core biopsies. As far as the best combination of sampling sites was selected, there was no statistical difference in cancer detection rates or in the characteristics of detected cancers between the TP and the TR subset biopsy schemes up to 12 cores. TP and TR biopsies performed equally, regardless of a history of negative biopsy, a digital rectal examination finding, the PSA level or the prostate volume.

CONCLUSIONS

We demonstrated for the first time that extended TP biopsy is as effective as its TR counterpart in detecting cancer and the characteristics of detected cancers, as far as sampling sites are selected to maximize the cancer detection rate.

Extended and saturation prostatic biopsy in the diagnosis and characterisation of prostate cancer: a critical analysis of the literature

OBJECTIVE

To review and critically analyse all the recent literature on the detection and characterisation of prostate cancer by means of extended and saturation protocols.

METHODS

A systematic review of the literature was performed by searching MedLine from January 1995 to April 2007. Electronic searches were limited to the English language, and the key words "prostate cancer," "diagnosis," "transrectal ultrasound (TRUS)," "prostate biopsy," and "prognosis" were used.

RESULTS

The prostate biopsy technique has changed significantly since the original Hodge sextant biopsy protocol. Several types of local anaesthesia are now available, but periprostatic nerve block (PPNB) has proved to be the most effective method to reduce pain during TRUS biopsy. It remains controversial whether PPNB should be associated with other medications. The optimal extended protocol (sextant template with at least four additional cores) should include six standard sextant biopsies, with additional biopsies (up to 12 cores) taken more laterally (anterior horn) to the base and medially to the apex. Repeat biopsies should be based on saturation biopsies (number of cores >/= 20) and should include the transition zone, especially in a patient with an initial negative biopsy. As a means of increasing accuracy of prostatic biopsy and reducing unnecessary prostate biopsy, colour and power Doppler imaging, with or without contrast enhancement, and elastography now can be successfully adopted, but their routine use is still controversial.

CONCLUSION

Extended and saturation biopsy schemes should be performed at first and repeat biopsy, respectively. The widespread use of local anaesthesia makes the procedures more comfortable.

A prospective randomized comparison of diagnostic efficacy between transperineal and transrectal 12-core prostate biopsy

The aim of this study is to elucidate the diagnostic efficacy between transperineal and transrectal 12-core prostate biopsy for prostate cancer. We prospectively randomized 200 consecutive men into two groups to undergo systematic prostate biopsy. Overall positivity for cancer was similar (47% by transperineal and 53% by transrectal; P=0.480). However, in case with 'gray zone' PSA (from 4.1 to 10.0 ng/ml), significantly more cores were positive when approach was transperineal, especially among transition zone cores. Therefore, urologist preferences are sufficient for choosing an approach, except for a possible small advantage of transperineal biopsy when PSA is in gray zone.

Imaging prostate cancer: a multidisciplinary perspective

The major goal for prostate cancer imaging in the next decade is more accurate disease characterization through the synthesis of anatomic, functional, and molecular imaging information. No consensus exists regarding the use of imaging for evaluating primary prostate cancers. Ultrasonography is mainly used for biopsy guidance and brachytherapy seed placement. Endorectal magnetic resonance (MR) imaging is helpful for evaluating local tumor extent, and MR spectroscopic imaging can improve this evaluation while providing information about tumor aggressiveness. MR imaging with superparamagnetic nanoparticles has high sensitivity and specificity in depicting lymph node metastases, but guidelines have not yet been developed for its use, which remains restricted to the research setting. Computed tomography (CT) is reserved for the evaluation of advanced disease. The use of combined positron emission tomography/CT is limited in the assessment of primary disease but is gaining acceptance in prostate cancer treatment follow-up. Evidence-based guidelines for the use of imaging in assessing the risk of distant spread of prostate cancer are available. Radionuclide bone scanning and CT supplement clinical and biochemical evaluation (prostate-specific antigen [PSA], prostatic acid phosphate) for suspected metastasis to bones and lymph nodes. Guidelines for the use of bone scanning (in patients with PSA level > 10 ng/mL) and CT (in patients with PSA level > 20 ng/mL) have been published and are in clinical use. Nevertheless, changes in practice patterns have been slow. This review presents a multidisciplinary perspective on the optimal role of modern imaging in prostate cancer detection, staging, treatment planning, and follow-up.