Needle core length in sextant biopsy influences prostate cancer detection rate

Importance of biopsy sample length for cancer diagnosis during trans-perineal prostate biopsy

OBJECTIVE

To identify the factors that determine the minimum length of biopsy sample required for accurate diagnosis.

MATERIALS AND METHODS

A retrospective analysis was conducted on 1202 cases that underwent rectal ultrasound-guided trans-perineal prostate biopsy (TPB) with standardized biopsy surgical procedures and pathological evaluation. Logistic regression correlation analysis and the imbalance between groups was eliminated by propensity score matching of patients' own factors between groups (positive group and negative group). ROC curve optimal threshold analysis were performed to identify the independent factors associated with cancer detection rate and the minimum length of biopsy sample required for accurate diagnosis.

RESULTS

The study included 1202 cases that underwent standardized 8-18 needle initial puncture biopsies from June 2020 to October 2023. The cancer detection rate was 40.02% (481/1202), with Gleason scores of 6, 7, 8, 9, and 10 in 164, 134, 107, 67, and 9 patients, respectively. The percentage of patients with clinical significance (International Society of Urological Pathology (ISUP) ≥ 2) was 65.90% (317/481). Multivariate analysis showed that age,prostate-specific antigen(PSA), prostate volume,positive multi-parametric magnetic resonance imaging (mp-MRI) and length of biopsy samples were significant factors (P < 0.05)。Interestingly, biopsy sample length did not correlate with the prostate volume (Pearson correlation P = 0.069). ROC curve analysis: The area under the curve AUC for sample length were 0.674 and 0.664 at before and after propensity score matching,respectively; the optimal thresholds were 12.25 mm and 11.00mm at before and after propensity score matching,respectively.

CONCLUSION

The independent predictors of cancer detection rate during TPB are age, PSA, prostate volume, positive mp-MRI, and sample length. Among these, sample length is the most critical indicator affecting puncture quality, and the minimum value of biopsy sample length to be obtained is 11.00mm.

Implications of a Novel Biopsy Downloading System on Prostate Cancer Detection Rate, Surveillance and Focal Therapy - A Prospective Study

OBJECTIVE

To examine the SmartBx, a novel biopsy downloading system, allowing downloading of biopsy cores with maximal core preservation as prostate biopsy sampling lacks preservation of core configuration & orientation.

METHODS

We prospectively collected cores from TRUS biopsy patients. Half were collected using the SmartBx & half using standard downloading. We measured length of the first ∼3200 cores through various pathology steps and within core cancer length in 160 SmartBx cores. We compared core length, yield (% of core available for final analysis/ original core on needle) and cancer detection rate between SmartBx and standard cores. T-test or chi-square were used for analysis.

RESULTS

6014 cores were collected from 429 patients. Core length (12.3mm vs. 10mm; P<.01) and core yield (77.5% vs. 62.2%; P<.01) were significantly higher using the SmartBx compared to standard method, respectively. Cancer detection rate was significantly higher using the SmartBx for patients with PSA<10 (10.1% vs. 7.96%; n=2080 & n=2073, respectively; P<.016). Other subgroups showed non-significant higher detection rate for SmartBx cores. We noticed higher detection rate of clinically significant prostate cancer. Within core cancer length in 160 SmartBx cores was significantly lower compared to standard positive whole cores (4.45mm vs. 10.9mm; P<.001). Assuming cancer site a perfect sphere, disease volume was 11-fold lower for within core compared to entire core (46.1mm vs. 679.9mm; P<.0001).

CONCLUSIONS

SmartBx results in significant higher core length, yield and cancer detection rate. Precise localization of within core tumor foci allows significant reduction in tumor volume.

Bevel angle study of flexible hollow needle insertion into biological mimetic soft-gel: Simulation and experimental validation

BACKGROUND

A thorough understanding of cutting-edge geometry and cutting forces of hollow biopsy needles are required to optimise needle tip design to improve fine needle aspiration procedures.

OBJECTIVES

To incorporate the dynamics of needle motion in a model for flexible hollow bevel tipped needle insertion into a biological mimetic soft-gel using parameters obtained from experimental work. Additionally, the models will be verified against corresponding needle insertion experiments.

METHODS

To verify simulation results, needle deflection and insertion forces were compared with corresponding experimental results acquired with an in-house developed needle insertion mechanical system. Additionally, contact stress distribution on needles from agar gel for various time scales were also studied.

RESULTS

For the 15°, 30°, 45°, 60° bevel angle needles, and 90° blunt needle, the percentage error in needle deflection of each needle compared to experiments, were 7.3%, 9.9%, 8.6%, 7.8%, and 9.7% respectively. Varying the bevel angle at the needle tip demonstrates that the needle with a lower bevel angle produces the largest deflection, although the insertion force does not vary too much among the tested bevel angles.

CONCLUSION

This experimentally verified computer-based simulation model could be used as an alternative tool for better understanding the needle-tissue interaction to optimise needle tip design towards improved biopsy efficiency.

Design Optimization of Nonrotational and Rotational Needle Insertion for Minimal Cutting Forces

The needle insertion is widely used in many medical procedures, particularly in the needle biopsy. The cutting force occurred during the insertion process has a significant effect on the cutting outcome. This paper focuses on minimizing the cutting force for two conventional needle insertion methods, the nonrotational and rotational needle insertion. For the nonrotational needle insertion, the secondary bevel angle and angle of rotation, which are two used for grinding the back-bevel and lancet needles, are considered. For the rotational needles, the effects of the insertion speed and the slice-push ratio on the cutting force are investigated. Levels of these design variables are defined using practical needle design configurations found in the literature. A clear trend of the cutting force decreases as the increase of the inclination angle was observed. The optimal cutting force of nonrotational needles was found as 0.242 N with inclination angle of 69.25 deg for the lancet needle and 0.254 N with inclination angle of 66.24 deg for the back-bevel needle. The optimization of rotational needles yielded a configuration of slice-push ratio as 4.66 and insertion speed as 2.01, which resulted in a minimal cutting force of 0.22 N. Besides, the main effects of and the interaction between the design variables on the cutting force are obtained and discussed. These results provide essential information for selecting geometric and cutting speed parameters for the design of nonrotational and rotational needles.

Three-dimensional greyscale transrectal ultrasound-guidance and biopsy core preembedding for detection of prostate cancer: Dutch clinical cohort study

Background

To overcome the limitations regarding two dimensional (2D) greyscale (GS) transrectal ultrasound (TRUS)-guided biopsy in prostate cancer (PCa) detection and tissue packaging in biopsy processing, there is an ongoing focus on new imaging and pathology techniques. A three-dimensional (3D) model of the prostate with biopsy needle guidance can be generate by the Navigo™ workstation (UC-care, Israel). The SmartBX™ system (UC-care, Israel) provides a prostate biopsy core preembedding method. The aim of this study was to compare cancer detection rates between the 3D TRUS-guidance and preembedding method with conventional 2D GS TRUS-guidance among patients undergoing prostate biopsies.

Methods

We retrospectively analyzed the records of all patients who underwent prostate biopsies for PCa detection at our institution from 2007 to 2016. The cohort was divided into a 2D GS TRUS-guidance cohort (from 2007 to 2013, n = 1149) and a 3D GS TRUS-guidance with preembedding cohort (from 2013 to 2016, n = 469). Effect of 3D GS TRUS-guidance with preembedding on detection rate of PCa and clinically significant PCa (Gleason score ≥ 7 or > 2 biopsy cores with a Gleason score 6) was compared to 2D GS TRUS-guidance using regression models.

Results

Detection rate of PCa and clinically significant PCa was 39.0 and 24.9% in the 3D GS TRUS cohort compared to 33.5 and 19.0% in the 2D GS TRUS cohort, respectively. On multivariate regression analysis the use of 3D GS TRUS-guidance with preembedding was associated with a significant increase in detection rate of PCa (aOR = 1.33; 95% CI: 1.03–1.72) and clinically significant PCa (aOR = 1.47; 95% CI: 1.09–1.98).

Conclusion

Our results suggest that 3D GS TRUS-guidance with biopsy core preembedding improves PCa and clinically significant PCa detection compared to 2D GS TRUS-guidance. Additional studies are needed to justify the application of these systems in clinical practice.

Electronic supplementary material

The online version of this article (10.1186/s12894-019-0455-7) contains supplementary material, which is available to authorized users.

Decision models for distinguishing between clinically insignificant and significant tumors in prostate cancer biopsies: an application of Bayes' Theorem to reduce costs and improve outcomes

Prostate cancer is the second leading cause of death from cancer, behind lung cancer, for men in the U. S, with nearly 30,000 deaths per year. A key problem is the difficulty in distinguishing, after biopsy, between significant cancers that should be treated immediately and clinically insignificant tumors that should be monitored by active surveillance. Prostate cancer has been over-treated; a recent European randomized screening trial shows overtreatment rates of 40%. Overtreatment of insignificant tumors reduces quality of life, while delayed treatment of significant cancers increases the incidence of metastatic disease and death. We develop a decision analysis approach based on simulation and probability modeling. For a given prostate volume and number of biopsy needles, our rule is to treat if total length of cancer in needle cores exceeds c, the cutoff value, with active surveillance otherwise, provided pathology is favorable. We determine the optimal cutoff value, c*. There are two misclassification costs: treating a minimal tumor and not treating a small or medium tumor (large tumors were never misclassified in our simulations). Bayes' Theorem is used to predict the probabilities of minimal, small, medium, and large cancers given the total length of cancer found in biopsy cores. A 20 needle biopsy in conjunction with our new decision analysis approach significantly reduces the expected loss associated with a patient in our target population about to undergo a biopsy. Longer needles reduce expected loss. Increasing the number of biopsy cores from the current norm of 10-12 to about 20, in conjunction with our new decision model, should substantially improve the ability to distinguish minimal from significant prostate cancer by minimizing the expected loss from over-treating minimal tumors and delaying treatment of significant cancers.

Longer biopsy cores do not increase prostate cancer detection rate: A large-scale cohort study refuting cut-off values indicated in the literature

OBJECTIVE

Only a few papers in the literature aimed to evaluate biopsy core lengths. Additionally, studies evaluated the core length with different approaches. We aimed to determine whether prostate cancer (PCa) detection is affected from core lengths according to three different approaches in a large standard cohort and compare our cut-off values with the published cut-offs.

MATERIAL AND METHODS

We retrospectively analyzed 1,523 initial consecutive transrectal ultrasound-guided 12-core prostate biopsies. Biopsies were evaluated with respect to total core length (total length of each patients' core) average core length (total core length divided by total number of cores in each patient), and mean core length (mean length of all cores pooled), and compared our cut-off values with the published cut-offs. The prostate volumes were categorized into four groups (<30, 30-59.99, 60-119.99, ≥120 cm³) and PCa detection rates in these categories were examined.

RESULTS

PCa was found in 41.5% patients. There was no difference between benign and malignant mean core lengths of the pooled cores (p>0.05). Total core length and average core length were not significantly associated with PCa in multivariate logistic regression analyses (p>0.05). The core lengths (mean, average and total core lengths) increased (p<0.001) and PCa rates decreased (p<0.001) steadily with increasing prostate volume categories. PCa percentages decreased in all categories above the utilized cut-offs for mean (p>0.05), average (p<0.05), and total core lengths (p>0.05).

CONCLUSION

There was no difference between mean core lengths of benign and malignant cores. Total core length and average core length were not significantly associated with PCa. Contrary to the cut-offs used for mean and average core lengths in the published studies, PCa rates decrease as these core lengths increase. Larger studies are necessary for the determination and acceptance of accurate cut-offs.

The 3DBiopsy Prostate Biopsy System: Preclinical Investigation of a Needle, Actuator, and Specimen Collection Device Allowing Sampling of Individualized Prostate Lengths Between 20 and 60 mm

OBJECTIVE

To increase the likelihood of detecting anterior cancers within the prostate and provide a specimen that spans the length of the gland. Newly designed 17- and 15-gauge (G) biopsy needles, a variable actuator, and an integrated pathology system intended for the longer cores were developed and tested for this purpose.

MATERIALS AND METHODS

Testing was performed comparing 2 common cannula tip grinds, a Vet-point (sharp tip) and a Menghini-point (atraumatic tip), and were tested against 18-G Bard Monopty in porcine kidney. A variable actuator was developed to fire the needle 20-60 mm and tested in cadaver prostates.

RESULTS

The aggregate firings for 3 different shot lengths comparing the Vet- with the Menghini-tip cannulas demonstrated 91% vs 85.2% fill (length of specimen/length of core bed, P = .007). A 15-G trocar needle with the Vet-tip cannula also had the best performance, with an aggregate standard deviation of 6.4% across 3 firing ranges and a minimum to maximum specimen length of 81%-105% of potential fill. Cadaver testing with the Vet-tip needles in the actuator for the transrectal (17-G) and transperineal (15-G) biopsies demonstrated mean fills of 93.3% and 76.5%, respectively. The new transrectal ultrasound needle obtained a 2-fold increase in specimen length over the standard Bard device (P <.001).

CONCLUSION

Longer and consistent cores were obtained using the new biopsy needles. Combined with an adjustable actuator, the physician can obtain specimens that include peripheral and anterior zone tissue in 1 core. Determination of cancer location on the longer specimens could enhance focal therapy planning.

The impact of core length on prostate cancer diagnosis during a standard 14-core prostate biopsy scheme

INTRODUCTION

Even if many studies in the literature purposed to evaluate the improvement of the prostate biopsy (PBx), few studies assessed the diagnostic value of core length in PBx. In this study, we evaluated the length of needle cores sampled during transrectal PBx (TRUSBx) and its impact on cancer diagnosis in a standard 14-core scheme.

METHODS

Medical records of 573 patients who underwent an initial TRUSBx with 14-cores scheme for suspicious prostate cancer (PCa) at our Department were reviewed. The PBx procedure and pathological evaluation were standardized. Cores lengths were compared in patients with versus without cancer, and were divided into group A and B, respectively. Statistical analysis was done to define an acceptable cut-off for biopsy length.

RESULTS

The mean age of the entire cohort was 62.1 ± 7.2 years, while median total prostate-specific antigen (PSA) and prostate volume were 4.2 ng/ml and 44.7 ml, respectively. PCa was showed in 33.3% of patients. Mean core length in group A versus B was 11.9 ± 3.9 versus 11.1 ± 3.2 mm (p = 0.016). Thus, core lengths were significantly longer in patients with cancer. There were no statistically significant differences when we considered the whole length of cores sampled from the right lobe (p = 0.58) and left lobe (p = 0.34).

CONCLUSIONS

The cancer detection rates in cores may be increased by core length in PCa patients during a TRUSBx. Our results suggest a core length of greater than 11.8 mm as a cut-off for quality warranty.

Does length of prostate biopsy cores have an impact on diagnosis of prostate cancer?

OBJECTIVE

To investigate whether core length is a significant biopsy parameter in the detection of prostate cancer.

MATERIAL AND METHODS

We retrospectively analyzed pathology reports of the specimens of 188 patients diagnosed with prostate cancer who had undergone initial transrectal ultrasound (TRUS) guided prostate biopsy, and compared biopsy core lengths of the patients with, and without prostate cancer. The biopsy specimens of prostate cancer patients were divided into 3 groups according to core length, and the data obtained were compared (Group 1; total core length <10 mm, Group 2; total core length 10 mm-19 mm, and Group 3; total core length >20 mm). Biopsy core lengths of the patients diagnosed as prostate cancer, and benign prostatic hyperplasia were compared, and a certain cut-off value for core length with optimal diagnostic sensitivity and specificity for prostate cancer was calculated.

RESULTS

Mean age, PSA and total length of cores were 65.08±7.41 years, 9.82±6.34 ng/mL and 11.2±0.2 mm, respectively. Assessment of biopsy core lengths showed that cores with cancer (n=993, median length 12.5 mm) were significantly longer than benign cores (n=1185, median length=11.3 mm) (p<0.001). Core length analysis yielded 12 mm cores have an optimal sensitivity (41.9%) and specificity (62%) for detection of cancer (odds ratio: 1.08).

CONCLUSION

Biopsy core length is one of the most important parameter that determines the quality of biopsy and detection of prostate cancer. A median sample length of 12 mm is ideal lower limit for cancer detection, and biopsy procedures which yield shorter biopsy cores should be repeated.

Evaluation of an Automated Analysis Tool for Prostate Cancer Prediction Using Multiparametric Magnetic Resonance Imaging

OBJECTIVE

To evaluate the diagnostic performance of an automated analysis tool for the assessment of prostate cancer based on multiparametric magnetic resonance imaging (mpMRI) of the prostate.

METHODS

A fully automated analysis tool was used for a retrospective analysis of mpMRI sets (T2-weighted, T1-weighted dynamic contrast-enhanced, and diffusion-weighted sequences). The software provided a malignancy prediction value for each image pixel, defined as Malignancy Attention Index (MAI) that can be depicted as a colour map overlay on the original images. The malignancy maps were compared to histopathology derived from a combination of MRI-targeted and systematic transperineal MRI/TRUS-fusion biopsies.

RESULTS

In total, mpMRI data of 45 patients were evaluated. With a sensitivity of 85.7% (with 95% CI of 65.4-95.0), a specificity of 87.5% (with 95% CI of 69.0-95.7) and a diagnostic accuracy of 86.7% (with 95% CI of 73.8-93.8) for detection of prostate cancer, the automated analysis results corresponded well with the reported diagnostic accuracies by human readers based on the PI-RADS system in the current literature.

CONCLUSION

The study revealed comparable diagnostic accuracies for the detection of prostate cancer of a user-independent MAI-based automated analysis tool and PI-RADS-scoring-based human reader analysis of mpMRI. Thus, the analysis tool could serve as a detection support system for less experienced readers. The results of the study also suggest the potential of MAI-based analysis for advanced lesion assessments, such as cancer extent and staging prediction.

Use of individual containers for prostate biopsy samples: Do we gain diagnostic performance?

OBJECTIVE

Prostate cores from transrectal biopsies are usually sent in separate vials for pathological processing. Although this is a common practice, there are controversial studies on its usefulness. We wanted to compare the rate of prostate cancer diagnosis between processing samples in 2 containers and processing them in individual containers to see if there are differences. Our secondary objective was to check the rate of diagnosis of various tumour subtypes in each of the 2 groups.

MATERIAL AND METHODS

A retrospective observational study was conducted of 2,601 cases of prostate biopsies. Ten cores were extracted in each biopsy. We divided the sample into 2 groups: biopsies sent in 2 containers to the department of pathology (left and right lobes) or sent in 10 (one for each cylinder), according to the different criteria used in our centre in the past. We then classified the cases according to the absence of neoplasia, insignificant tumour (involvement of just 1 cylinder, <5%, Gleason score<7), Gleason 6 or Gleason≥7. A bivariate statistical analysis was performed using the chi-squared test.

RESULTS

A total of 1,777 participants were included in the 2-container group, and 824 were included in the 10-container group. We diagnosed a rate of 32.4% of cancers in the 2-container group and 40% in the 10-container group, a difference that was statistically significant (P<.001). The insignificant carcinomas were diagnosed more often in the 2-container group than in the 10-container group (6.4% vs. 4.3%, respectively; P=.03). Samples with a Gleason score of 6 were diagnosed more often in the 10-container group than in the 2-container group (11.9% vs. 8.1%, respectively; P=.002). The same occurred with the Gleason score≥7 (23.8% in the 10-container group vs. 17.9% in the 2-container group; P<.001).

CONCLUSIONS

We diagnosed more prostate cancers when sending biopsied cores in individual containers. Once the procedure was conducted, we also observed in our series a reduction in the diagnoses of insignificant carcinoma to the detriment of an increased diagnosis of not insignificant carcinomas.

Urologist's Impact on Needle Core Prostate Biopsy Histopathologic Variables Within a Single Institution

OBJECTIVE

To assess the urologist's impact on prostate needle core biopsy variables including number of containers submitted, total core length, longest core length, and individual core length threshold values, and to elucidate the relationship between these variables and cancer detection rate within a recent cohort.

METHODS

A retrospective search was performed to identify patients who had an extended transrectal ultrasound-guided prostate needle core biopsy between 2008 and 2013.

RESULTS

One thousand one prostate biopsies were analyzed. Total core length (mean 13.2-22.9 cm, P < .001) significantly varied by submitting urologist but did not impact cancer detection rate per case. Increased core length per container impacted the cancer detection per container (P < .001). The number of cores that met threshold values of 0.5, 1.0, and 1.5 cm as well as longest individual core length (mean 1.7-2.2 cm) significantly varied between urologist (P < .001), although there was no association between these variables and cancer detection. Container number differed significantly between urologists (P < .001) but did not correlate with cancer detection. For the single urologist with a change in his submission protocol during the study period, a nonsignificant change in cancer detection was noted when comparing 12-14 containers vs 6-9 containers.

CONCLUSION

Submitting urologist significantly impacts prostate biopsy metrics. An increased amount of tissue per container was associated with higher rates of cancer per container. A nonsignificant change in cancer detection rate was observed when container number was reduced from 12-14 to 6-9.

Clinical value of core length in contemporary multicore prostate biopsy

Objectives

There is little data about the clinical value of core length for prostate biopsy (PBx). We investigated the clinical values of various clinicopathological biopsy-related parameters, including core length, in the contemporary multi-core PBx.

Patients and Methods

Medical records of 5,243 consecutive patients who received PBx at our institution were reviewed. Among them, 3,479 patients with prostate-specific antigen (PSA) ≤10ng/ml level who received transrectal ultrasound (TRUS)-guided multi (≥12)-core PBx at our institution were analyzed for prostate cancer (PCa). Gleason score upgrading (GSU) was analyzed in 339 patients who were diagnosed with low-risk PCa and received radical prostatectomy. Multivariate logistic regression analyses for PCa detection and prediction of GSU were performed.

Results

The mean age and PSA of the entire cohort were 63.5 years and 5.4ng/ml, respectively. The overall cancer detection rate was 28.5%. There was no statistical difference in core length between patients diagnosed with PCa and those without PCa (16.1 ± 1.8 vs 16.1 ± 1.9mm, P = 0.945). The core length was also not significantly different (16.4 ± 1.7 vs 16.4 ± 1.6mm, P = 0.889) between the GSU group and non-GSU group. Multivariate logistic regression analyses demonstrated that the core length of PBx did not affect PCa detection in TRUS-guided multi-core PBx (P = 0.923) and was not prognostic for GSU in patients with low-risk PCa (P = 0.356).

Conclusions

In patients undergoing contemporary multi-core PBx, core length may not have significant impact on PCa detection and also GSU following radical prostatectomy among low-risk PCa group.

Prostate Biopsy Core Handling: Comparison of Contemporary Preembedding Methods

INTRODUCTION

The probability of prostate cancer detection is related to the amount of tissue represented. For optimal tissue representation, the specimens should preserve their regular cylindrical shape and avoid artefacts and deformation caused by fixation and preembedding. The aim of our study was to compare contemporary preembedding methods including a new method of using thick cardboard.

MATERIALS AND METHODS

To compare the preembedding methods, we took 36 nonfragmented cores from fresh prostatectomy specimens for each method, fixed them in formalin and made histological slides. The comparison criteria were a core section area in the middle section and the number of fragments per core after processing.

RESULTS

Two methods (preembedding on the edge of thick cardboard and on biplicated paper) provided a bigger section area of specimens. The differences in amounts of fragments were very small among the methods mentioned above and the preembedding glass with grooves, but preembedding between two sponges in a histological cassette showed higher fragmentation.

CONCLUSIONS

Preembedding on the edge of thick cardboard and on biplicated paper can be recommended as effective methods of prostate biopsy core fixation. Paper or cardboard for fixation of prostate biopsy cores should be presoaked with formalin or normal saline.

Minimum 6 mm core length is strongly predictive for the presence of glandular tissue in transrectal prostate biopsy

INTRODUCTION

Prostate biopsy guidelines recommend that a prostate biopsy not containing glandular prostate tissue should be reported as inadequate. In the literature, there is a lack of any study that addresses the relationship between the length of biopsy cores and the absence of glandular prostate tissue. In this study, we aimed to determine whether a relationship exists between these parameters.

MATERIALS AND METHODS

We retrospectively evaluated 1,712 consecutive initial transrectal 12-core prostate biopsies. Individual cores were histologically categorized as glandular (benign or malignant) and non-glandular (rectal mucosa, periprostatic adipose tissue, prostatic or periprostatic fibromuscular tissue). Total number of evaluable cores ≤9, highly fragmented, incorrectly numbered or dried biopsies, patients with 5-α reductase inhibitory treatment were excluded.

RESULTS

We analyzed remaining 1,584 patients; 41.7 % had adenocarcinoma. A total of 19,144 cores were sampled. Non-glandular cores were found significantly shorter than glandular cores (p < 0.0001). The percentages of non-glandular cores were significantly higher at the base, apex and lateral biopsy sites (p < 0.0001). We found a 6-mm cutoff value for accurate prediction of glandular sampling with 80.2 % sensitivity and 78.7 % specificity. The risk of non-glandular sampling increased 15-fold in cores ≤6 mm (OR 14.91, 95% CI 13.20-16.83, p < 0.0001).

CONCLUSIONS

Non-glandular sampling was directly associated with shorter core lengths. They were found significantly higher at the base, apex and lateral localizations. We found a 6-mm cutoff value for the prediction of non-glandular samples before the histologic evaluation. Below this value, the risk of non-glandular sampling increased 15-fold. We suggest it for prompt additional sampling during biopsy procedure.

Length of prostate biopsies is not necessarily compromised by pooling multiple cores in one paraffin block: an observational study

Background

Individually submitted prostatic needle biopsies are recommended by most guidelines because of their potential advantage in terms of core quality. However, unspecified bilateral biopsies are commonly submitted in many centers. The length of the core is the key quality indicator of prostate biopsies. Because there are few recent publications comparing the quality of 12 site-designated biopsies versus pooled biopsies, we compared the lengths of the biopsies obtained by both methods.

Methods

The material was obtained from 471 consecutive subjects who underwent prostatic needle biopsy in the Tampere University Hospital district between January and June 2013. Biopsies from 344 subjects fulfilled the inclusion criteria. The total number of cores obtained was 4047. The core lengths were measured on microscope slides. Extraprostatic tissue was subtracted from the core length.

Results

The aggregate lengths observed were 129.5 ± 21.8 mm (mean ± SD) for site-designated cores and 136.9 ± 26.4 mm for pooled cores (p = 0.09). The length of the core was 10.8 ± 1.8 mm for site-designated cores and 11.4 ± 2.2 mm for pooled cores (p = 0.87). The median length for pooled cores was 11 mm (range 5 mm – 18 mm). For individual site-designated cores, the median length was 11 mm (range 7 mm −15 mm). The core length was not correlated with the number of cores embedded into one paraffin block (r = 0.015). There was no significant difference in cancer detection rate (p = 0.62).

Conclusions

Our results suggest that unspecified bilateral biopsies do not automatically lead to reduced core length. We conclude that carefully embedded multiple (three to nine) cores per block may yield cores of equal quality in a more cost-efficient way and that current guidelines favoring individually submitted cores may be too strict.

Gleason underestimation is predicted by prostate biopsy core length

PURPOSE

To evaluate whether core length impacts biopsy accuracy and Gleason score underestimation compared to radical prostatectomy (RP) specimens.

METHODS

From 2010 to 2011, 8,928 cores were trans-rectal obtained from 744 consecutive patients (178 RP, 24%), 557 by an experienced performer (>250/year) and 187 (25%) by in-training urology residents. Prospectively analyzed variables were core length, age, prostate volume, free and total prostate-specific antigen (PSA), PSA density and free/total PSA ratio.

RESULTS

Mean core length for Gleason upgrading on RP (42.7%, n = 76) was 11.61 (±2.5, median 11.40) compared to 13.52 (±3.2, median 13.70), p < 0.001 for perfect biopsy-RP Gleason agreement (57.3%, n = 102). In multivariate analysis, for each unit of core length increment in millimeter, the Gleason upgrading risk decreased 89.9%, p = 0.049 [odds ratio (OR) 0.10, 95% confidence interval (CI) 0.01-0.99]. Biopsy positivity between experienced (35.5%) and in-training performer (30.1%) was not significantly different (p = 0.20), with comparable mean patient age (65.1 vs. 64.1), prostate volume (52.3 vs. 50.7) and median PSA (5.2 vs. 5.1), respectively. Denoting wider variability in terms of core length, in-training performers obtained significantly larger cores for positive biopsies (11.33 ± 3.42 vs. 10.83 ± 3.68), p = 0.043, compared to experienced performer (11.39 ± 3.36 vs. 11.37 ± 3.64), p = 0.30. In multivariate analysis, PSA density (OR 1.14, 95% CI 1.02-1.28) and age (OR 1.04, 95% CI 1.01-1.07) were significantly associated with biopsy positivity, p = 0.021 and p = 0.011, respectively.

CONCLUSION

While core length on trans-rectal biopsy independently affects Gleason upgrading on RP specimens, performer experience has minor impact on Gleason discordance or biopsy positivity due to a sharp learning curve.

Significance of atypical small acinar proliferation and extensive high-grade prostatic intraepithelial neoplasm in clinical practice

INTRODUCTION

Prostate cancer (PCa) is one of the most commonly diagnosed neoplasms in elderly men. The precancerous lesion of PCa is considered a high-grade prostate intraepithelial neoplasm (HG-PIN), while atypical small acinar proliferation (ASAP) is commonly considered as an under-diagnosed cancer. The aim of the study was to establish the impact of ASAP and extensive HG-PIN on pre-biopsy prostate-specific antigen (PSA) levels and the risk of cancer development in subsequent biopseis.

MATERIAL AND METHODS

The 1,010 men suspected for PCa were included in the study based on elevated PSA, and/or positive rectal examination. Transrectal ultrasound (TRUS) guided 10 core biopsy was performed. In those with extensive HG-PIN or ASAP on the first biopsy, and/or elevated PSA value, a second biopsy was performed.

RESULTS

In the second biopsy, PCa was diagnosed in 6 of 19 patients (31.57%) with extensive HG-PIN, in four of 40 (10%) with BPH, and in 4 of 18 (22.22%) with ASAP. There was a statistically significant difference between the values of PSA in the group of patients with ASAP in comparison to those with benign prostate hyperplasia (BPH) (p = 0.005) as well as in patients with HG-PIN in comparison to BPH (p = 0.02).

CONCLUSIONS

A precancerous lesion diagnosed upon biopsy causes a statistically significant increase in the values of PSA in relation to BPH, as well as in the case of ASAP and extensive HG-PIN. The estimate of risk of PCa diagnosis in patients with ASAP and those with extensive HG-PIN in the first biopsy is comparable, which is why there are no reasons for different treatment of patients with the above-mentioned diagnoses. Both should be subjected to urgent second biopsy in around the 4-6 weeks following the initial biopsy.

Transrectal prostate biopsy

Grayscale transrectal ultrasonographic prostate biopsy using local anesthesia remains the standard approach to the definitive diagnosis of prostate cancer. Careful patient evaluation and preparation are essential to maximize the results and minimize the complications of the biopsy procedure.

Does needle calibre affect pain and complication rates in patients undergoing transperineal prostate biopsy? A prospective, randomized trial

Transperineal prostate biopsy is a procedure that can be used to obtain histological samples from the prostate. To improve both the quality of the biopsy core samples and prostate cancer detection, we are currently performing a prospective, randomized trial comparing prostate biopsy samples obtained using an 18 G-needle to those obtained using a 16 G needle. The aim of this preliminary study was to evaluate pain and complication rates in both groups in order to assess whether performing a prostate biopsy with a larger calibre needle is a feasible procedure. One hundred and eighty-seven patients undergoing transperineal prostate biopsy were prospectively evaluated and divided into two groups. The first group (94 patients, Group A) received a transperineal prostate biopsy using a 16 G-needle and the second group (93 patients, Group B) underwent transperineal prostate biopsy with an 18 G-needle. Anaesthesia was obtained with a single perineal injection at the prostatic apex in all subjects. A visual analogue scale (VAS) and facial expression scale (FES) were used to assess pain during multiple steps of the procedure in each group. A detailed questionnaire was used to obtain information about drug use because it could potentially influence the pain and complications that patients experienced. Two weeks after the procedure, early and late complications were evaluated. Statistical analysis was carried out using non-parametric tests. Prostate Specific Antigen (PSA) and drug use were similar at baseline between the two groups. Pain during prostate biopsy, which was measured with both the VAS and FES instruments, did not differ significantly between the 18- and 16 G-needle groups, and no significant differences were found in early or late complication rates between the groups. Transperineal prostate biopsy with a 16 G-needle is a feasible procedure in terms of pain and complication rates. Further studies with larger patient populations are required to assess whether or not this procedure can improve prostate cancer detection rates.

Targeted prostate biopsy using statistical image analysis

In this paper, a method for maximizing the probability of prostate cancer detection via biopsy is presented, by combining image analysis and optimization techniques. This method consists of three major steps. First, a statistical atlas of the spatial distribution of prostate cancer is constructed from histological images obtained from radical prostatectomy specimen. Second, a probabilistic optimization framework is employed to optimize the biopsy strategy, so that the probability of cancer detection is maximized under needle placement uncertainties. Finally, the optimized biopsy strategy generated in the atlas space is mapped to a specific patient space using an automated segmentation and elastic registration method. Cross-validation experiments showed that the predictive power of the optimized biopsy strategy for cancer detection reached the 94%-96% levels for 6-7 biopsy cores, which is significantly better than standard random-systematic biopsy protocols, thereby encouraging further investigation of optimized biopsy strategies in prospective clinical studies.

Transperineal TRUS-Guided Prostate Biopsy

Prostate biopsy can be performed through different approaches, with several differences in patient preparation, procedural technique and post-biopsy patient management. On the basis of our personal experience, and comparing it with literature data, this paper presents our data reviews regarding enema and antibiotic prophylaxis administration, biopsy technique, prostate sampling, core pathological management and post-operative management. We also provide a possible standardization of these procedures in patients undergoing transperineal TRUS-guided prostate biopsy. We accordingly classify antibiotic prophylaxis and bowel preparation as optional/advisable, ultrasound prostate examination before biopsy and local anaesthesia as recommended. Prostate sampling should be performed with at least 8 cores, to be increased proportionally to prostate volume. Each sample should be sent to the pathologist in single containers, according to the pre-embedding sandwich method. Finally, the patient should be evaluated for early complications before discharging, and for delayed complications within one month after the procedure. (Urologia 2007; 74: 1–7)

Needle Core Length is a Quality Indicator of Systematic Transperineal Prostate Biopsy

OBJECTIVE

To analyse the length of needle cores sampled as a quality indicator in systematic transperineal prostate biopsy. We assessed the correlation of core length with the other clinical and topographic parameters.

MATERIAL AND METHODS

We prospectively evaluated data from 509 consecutive patients who underwent a first set of transrectal ultrasound-guided transperineal prostate biopsy for suspected prostate cancer. Fourteen cores were sampled from each patient. Needle cores were stretched and placed in tissue cassettes between two nylon meshes according to the pre-embedding methods of prostate needle biopsy specimens. For single biopsy core, the measurement of length (in millimetres) and any percentage of cancer in the biopsy specimen were reported.

RESULTS

The mean length of 7,126 analysed cores was 14.14+/-4.35mm. All cores were longer than 10mm. The mean length of needle cores sampled did not correlate with patient age, total prostate-specific antigen value, digital rectal examination, and prostate volume. The whole mean length of the six samples from the peripheral zone of the right lobe was higher than the mean corresponding value of the six samples from the left lobe peripheral zone (p<0.001). The transperineal approach allows a greater sampling of the prostate apex than of the midgland and prostate base (p<0.001).

CONCLUSIONS

The length of the needle cores sampled during transperineal prostate biopsy fulfils the parameters of quality required by pathologists for an appropriate evaluation of the biopsy specimen.

Atypical Small Acinar Proliferation in the Prostate: Clinical Significance in 2006

About 2% of contemporary prostate needle biopsy specimens contain collections of small acini that are suspicious for cancer but that fall below the diagnostic threshold and are reported as atypical small acinar proliferation suspicious for but not diagnostic of malignancy. Prostate cancer has been identified in specimens from subsequent biopsies in up to 60% of cases of atypical small acinar proliferation, indicating that this finding is a significant predictor of cancer. Identification of atypical small acinar proliferation warrants repeat biopsy for concurrent or subsequent invasive carcinoma.

Diagnostic value of systematic biopsy methods in the investigation of prostate cancer: a systematic review

PURPOSE

Several new extended prostate biopsy schemes (greater than 6 cores) have been proposed. We compared the cancer detection rates and complications of different extended prostate biopsy schemes for diagnostic evaluation in men scheduled for biopsy to identify the optimal scheme.

MATERIALS AND METHODS

In a systematic review we searched 13 electronic databases, screened relevant urological journals and the reference lists of included studies, and contacted experts. We included studies that compared different systematic prostate biopsy methods using sequential sampling or a randomized design in men scheduled for biopsy due to suspected prostate cancer. We pooled data using a random effects model when appropriate.

RESULTS

We analyzed 87 studies with a total of 20,698 patients. We pooled data from 68 studies comparing a total of 94 extended schemes with the standard sextant scheme. An increasing number of cores were significantly associated with the cancer yield. Laterally directed cores increased the yield significantly (p = 0.003), whereas centrally directed cores did not. Schemes with 12 cores that took additional laterally directed cores detected 31% more cancers (95% CI 25 to 37) than the sextant scheme. Schemes with 18 to 24 cores did not detect significantly more cancers. Adverse events for schemes up to 12 cores were similar to those for the sextant pattern. Adverse event reporting was poor for schemes with 18 to 24 cores.

CONCLUSIONS

Prostate biopsy schemes consisting of 12 cores that add laterally directed cores to the standard sextant scheme strike the balance between the cancer detection rate and adverse events. Taking more than 12 cores added no significant benefit.

Current prostate biopsy interpretation: criteria for cancer, atypical small acinar proliferation, high-grade prostatic intraepithelial neoplasia, and use of immunostains

CONTEXT

The past decade has brought major changes in prostate biopsy sampling, interpretation, and reporting.

OBJECTIVE

To summarize current information on diagnostic decision making, Gleason grading, "atypical" diagnoses, and use of immunostaining.

DATA SOURCES

Pertinent literature from 1985 to 2005 is reviewed, emphasizing recent findings.

CONCLUSIONS

Diagnosis begins by evaluating a focus of atypical single-cell layer lined acini according to the 3 minimal diagnostic criteria for cancer: an infiltrative pattern, nuclear enlargement and hyperchromasia, and prominent nucleoli. The Gleason score and linear extent or percent of each core containing cancer should be reported. Atypical small acinar proliferation suspicious for malignancy designates foci that have either qualitative or quantitative limitations in atypia precluding a definite cancer diagnosis. It has about a 3% incidence as an isolated finding. Contemporary studies indicate a 39% predictive value for cancer on repeat biopsy. Isolated high-grade prostatic intraepithelial neoplasia has a 3% to 14% incidence and predicts cancer on repeat biopsy in 23% of cases. Immunostaining for a marker of benign prostate (cytoplasmic keratin 34betaE12 or nuclear p63) and a marker of cancer (alpha-methylacyl coA racemase, clone P504S) may or may not resolve atypical small acinar proliferation diagnoses. Performance of 34betaE12 and P504S immunostains resolved 76% of atypical small acinar proliferation diagnoses per consensus of 3 urologic pathologists studied; a technical limitation is preservation of the focus in question on the levels used for immunostaining.

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.

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.

Can We Obtain Better Specimens with an End-Cutting Prostatic Biopsy Device?

OBJECTIVE

Our aim was to compare the tissue yield of two different prostate biopsy instruments: the newer end-cut versus standard side-notch technique.

METHODS

A total of 87 patients, who underwent transrectal ultrasound guided prostate biopsy were included in the study between February 2003 and July 2003. Twenty-five patients underwent prostate biopsy with the end-cut technique with a stroke length of 33 mm (EC-33), 25 patients were biopsied with a stroke length of 23 mm of the same instrument (EC-23) whereas the remaining 37 patients underwent biopsy with an instrument working with side-notch technique with a 22 mm stroke length (SN). The length, weight and weight/length ratio (WLR) were measured for each biopsy core. The pathologic specimens were evaluated qualitatively. The length, weight and WLR as well as the complication rates, pain, zero biopsy rates, pathologic quality and cancer detection rates were compared between the groups.

RESULTS

Three groups were similar according to age, PSA values (free, total, free/total), prostate volumes (TZ, total) and PSA densities. The cancer detection rate was not statistically different between groups and was overall 20,9%. As the groups were compared according to mean core lengths, weights and densities the sequence was found to be EC-33>EC-23>SN. The EC group had higher prostatic glandular capture rates and better pathological quality. However, the zero biopsy rates were 12%, 7% and 1% for EC-33, EC-23 and SN groups, respectively and the difference was statistically significant. The complication rates after biopsy were similar for each group. The mean visual analogous scale scores were not significantly different between the groups. Another interesting finding was that cores containing cancer were heavier and denser than the others regardless of the instrument type.

CONCLUSION

The use of the presented new instrument, enables to obtain longer, heavier and denser cores with a higher pathologic quality and glandular coverage without increasing the number of biopsies and morbidity. However, the relatively high zero biopsy rate is a handicap that needs to be improved.

The Long Core Needle with an End-Cut Technique for Prostate Biopsy: Does It Really Have Advantages When Compared with Standard Needles?

OBJECTIVE

To evaluate the failure rate, core length and fragmentation rate for each different stroke length of the end-cut (BioPince) needle in order to show the performance of the needle for different stroke lengths and compare these with the standard side-notch needle.

METHODS

TRUS guided biopsy of the prostate was performed on 86 consecutive men between June 2002 and May 2003. The patients were randomized into two groups with 43 men in each group. Patients in group A underwent 8 core biopsy with the end-cut needle in different stroke lengths; 13, 23 and 33mm respectively. Patients in group B underwent 8 core biopsy with the side-notch needle. The cores have been evaluated and compared for failure rates, core lengths, number of core lengths under 5mm and fragmentation rates.

RESULTS

When the end-cut needle was used, a significant number of failure rates was noted; with an overall failure rate of 16%. The failure rates were 26% for 13mm stroke length, 18% for 23mm stroke length and 10% for 33mm stroke length respectively. These failure rates showed statistically significant difference from standard needle for overall and for every separate stroke length ( p<0.001 for all). Standard needle and the cores taken with 33mm stroke length of the end-cut needle had similar low fragmentation rates while 13 and 23mm stroke lengths had higher rates. Of the overall cores taken by BioPince needle, 46/344 (13%) of the cores were shorter than 5mm and this was significantly higher than the standard needle with 3/344 cores less than 5mm ( p<0.001). The end-cut needle when used with the 33mm stroke length has improved the core length by 68% according to the standard side-notch needle.

CONCLUSIONS

Our results showed that the performance of the end-cut needle worsens with decreased stroke lengths. The end-cut needle showed high failure rates which necessitates new punctures for taking a core. Additionally, the fragmentation rates are not lower than the standard needle and it has higher rates of taking small core samples. The only significant advantage of this needle over the standard needle is taking longer cores when it has been used at 33mm stroke lengths.

Guidelines for processing and reporting of prostatic needle biopsies

The reported detection rate of prostate cancer, lesions suspicious for cancer, and prostatic intraepithelial neoplasia (PIN) in needle biopsies is highly variable. In part, technical factors, including the quality of the biopsies, the tissue processing, and histopathological reporting, may account for these differences. It has been thought that standardisation of tissue processing might reduce the observed variations in detection rate. Consensus among the members of the pathology committee of the European Randomised study of Screening for Prostate Cancer (ERSPC) concerning the optimal methodology of tissue embedding resulting in guidelines for prostatic needle biopsy processing was reached. The adoption of an unequivocal and uniform way of reporting lesions encountered in prostatic needle biopsies is considered helpful for decision taking by the clinician. The definition of parameters for quality control of prostatic needle biopsy diagnostics will further facilitate clinical epidemiological multicentre studies of prostate cancer.

Contemporary pathology of prostate cancer

In less than 20 years since the introduction of serum PSA and the spring-loaded 18-gauge prostatic biopsy needle, pathologists have adjusted to the limited tissue requirements of narrow needle specimens to apply criteria for diagnosis and grading of prostate cancer, borrowing from lessons learned from radical prostatectomies. Substantial gains have been made during this period in the understanding of precancerous lesions, mimics of malignancy, the criteria for minimal cancer, variants of cancer, and treatment-induced changes. The light microscopic findings remain the criterion standard for diagnosis against which all new techniques should be measured. Numerous findings have proven to be of value, including simple quantitation of histopathologic features, cancer volume, perineural invasion, and others.