Does site-specific labelling and individual processing of sextant biopsies improve the accuracy of prostate biopsy in predicting pathological stage in patients with T1c prostate cancer?

Standards for prostate biopsy

PURPOSE OF REVIEW

A variety of techniques have emerged for the optimization of prostate biopsy. In this review, we summarize and critically discuss the most recent developments regarding the optimal systematic biopsy and sampling labeling along with multiparametric MRI and magnetic resonance-targeted biopsies.

RECENT FINDINGS

The use of 10-12-core-extended sampling protocols increases cancer detection rates compared with traditional sextant sampling and reduces the likelihood that patients will require a repeat biopsy, ultimately allowing more accurate risk stratification without increasing the likelihood of detecting insignificant cancers. As the number of cores increases above 12 cores, the increase in diagnostic yield becomes marginal. However, the limitations of this technique include undersampling, oversampling, and the need for repetitive biopsy. MRI and magnetic resonance-targeted biopsies have demonstrated superiority over systematic biopsies for the detection of clinically significant disease and representation of disease burden, while deploying fewer cores and may have applications in men undergoing initial or repeat biopsy and those with low-risk cancer on or considering active surveillance.

SUMMARY

A 12-core systematic biopsy that incorporates apical and far-lateral cores in the template distribution allows maximal cancer detection, avoidance of a repeat biopsy while minimizing the detection of insignificant prostate cancers. MRI-guided prostate biopsy has an evolving role in both initial and repeat prostate biopsy strategies, as well as active surveillance, potentially improving sampling efficiency, increasing the detection of clinically significant cancers, and reducing the detection of insignificant cancers.

Optimization of initial prostate biopsy in clinical practice: sampling, labeling and specimen processing

PURPOSE

An optimal prostate biopsy in clinical practice is based on a balance among adequate detection of clinically significant prostate cancers (sensitivity), assuredness regarding the accuracy of negative sampling (negative predictive value), limited detection of clinically insignificant cancers and good concordance with whole gland surgical pathology results to allow accurate risk stratification and disease localization for treatment selection. Inherent within this optimization is variation of the core number, location, labeling and processing for pathological evaluation. To date, there is no consensus in this regard. The purpose of this review is to 1) define the optimal number and location of biopsy cores during primary prostate biopsy among men with suspected prostate cancer, 2) define the optimal method of labeling prostate biopsy cores for pathological processing which will provide relevant and necessary clinical information for all potential clinical scenarios, and 3) determine the maximal number of prostate biopsy cores allowable within a specimen jar which would not preclude accurate histological evaluation of the tissue.

MATERIALS AND METHODS

A bibliographic search using PubMed® covering the period up to July 2012 yielded approximately 550 articles. Articles were reviewed and categorized based on which of the 3 objectives of this review was addressed. Data were extracted, analyzed and summarized. Recommendations are provided based on this literature review and our clinical experience.

RESULTS

The use of 10 to 12-core extended sampling protocols increases cancer detection rates compared to traditional sextant sampling methods and reduces the likelihood of repeat biopsy by increasing negative predictive value, ultimately allowing more accurate risk stratification without increasing the likelihood of detecting insignificant cancers. As the number of cores increases above 12, the increase in diagnostic yield becomes marginal. Only limited evidence supports the use of initial biopsy schemes involving more than 12 cores or saturation. Apical and laterally directed sampling of the peripheral zone increases cancer detection rate, reduces the need for repeat biopsies and predicts pathological features on prostatectomy while transition zone biopsies do not. There are little data to suggest that knowing the exact site of an individual positive biopsy core provides meaningful clinical information. However, determining laterality of cancer on biopsy may be helpful for predicting sites of extracapsular extension and therapeutic planning. Placement of multiple biopsy cores in a single container (greater than 2) appears to compromise pathological evaluation, which can reduce cancer detection rate and increase the likelihood of equivocal diagnoses.

CONCLUSIONS

A 12-core systematic biopsy that incorporates apical and far-lateral cores in the template distribution allows maximal cancer detection, avoids repeat biopsy, and provides information adequate for identifying men who need therapy and planning that therapy while minimizing the detection of occult, indolent prostate cancers. This literature review does not provide compelling evidence that individual site specific labeling of cores benefits clinical decision making regarding the management of prostate cancer. Based on the available literature, we recommend packaging no more than 2 cores in each jar to avoid reduction of the cancer detection rate through inadequate tissue sampling.

Specimen orientation by marking the peripheral end: (potential) clinical advantages in prostate biopsy

The aim of this paper is to identify advantages that could be obtained by orientation of the biopsy specimen using the marking technique. We reviewed our experience (4,500 cases) and the published literature. The peripheral (proximal) end of the fresh specimen is marked with ink soon after needle delivering in a few minutes. It is performed easily in association with pre-embedding method. Five potential clinical advantages were identified: (1) tumor localization, (2) atypical lesions localization and planning rebiopsy strategy, (3) planning surgical strategy, (4) selection criteria for focal therapy and active surveillance, and (5) cost reduction. Peripheral end marking is low cost, easy and reproducible. It drives several potential advantages in cancer diagnosis or isolated atypical lesions, in particular, spatial localization within the biopsy (transition versus peripheral zone, anterior versus posterior, subcapsular versus intraparenchima, and extraprostatic extension) should be easy and reliable. We can add a new pathological parameter: pathological orientation or biopsy polarity.

[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.

A new nomogram to predict pathologic outcome following radical prostatectomy

OBJECTIVE

To develop a preoperative nomogram to predict pathologic outcome in patients submitted to radical prostatectomy for clinical localized prostate cancer.

MATERIALS AND METHODS

Nine hundred and sixty patients with clinical stage T1 and T2 prostate cancer were evaluated following radical prostatectomy, and 898 were included in the study. Following a multivariate analysis, nomograms were developed incorporating serum PSA, biopsy Gleason score, and percentage of positive biopsy cores in order to predict the risks of extraprostatic tumor extension, and seminal vesicle involvement.

RESULTS

In univariate analysis there was a significant association between percentage of positive biopsy cores (p < 0.001), serum PSA (p = 0.001) and biopsy Gleason score (p < 0.001) with extraprostatic tumor extension. A similar pathologic outcome was seen among tumors with Gleason score 7, and Gleason score 8 to 10. In multivariate analysis, the 3 preoperative variables showed independent significance to predict tumor extension. This allowed the development of nomogram-1 (using Gleason scores in 3 categories - 2 to 6, 7 and 8 to 10) and nomogram-2 (using Gleason scores in 2 categories - 2 to 6 and 7 to 10) to predict disease extension based on these 3 parameters. In the validation analysis, 87% and 91.1% of the time the nomograms-1 and 2, correctly predicted the probability of a pathological stage to within 10% respectively.

CONCLUSION

Incorporating percent of positive biopsy cores to a nomogram that includes preoperative serum PSA and biopsy Gleason score, can accurately predict the presence of extraprostatic disease extension in patients with clinical localized prostate cancer.

Is quadrant biopsy sufficient in men likely to have advanced prostate cancer? Comparison with extended biopsy

We hypothesized that quadrant prostate biopsy (QPB) provides sufficient first-line pathological evaluation of patients with presumed advanced prostate cancer (PC). The aim of this study was to investigate whether the reduction of core number in first-line PB from 6-12 to 4 in patients with presumed advanced PC leads to loss of clinically relevant information. We retrospectively studied 113 men that underwent PB, classified in two groups: "H" (high) and "L" (low likelihood of having advanced PC), according to PSA, digital rectal and transrectal ultrasound findings. Pathological results of 6-12-core PB and QPB were retrospectively compared for the presence of malignancy, percentage of positive cores, Gleason score (GS), and the presence of high-grade prostatic intraepithelial neoplasia (HGPIN). PC detection rate was not impaired in group H but dropped significantly in group L, and the percentage of positive cores was not significantly changed in group H (p=0.39), but decreased in group L (p=0.04), due to sampling scheme reduction. No HGPIN was missed with QPB in group H, while 2 HGPINs were missed in group L. No significant change in GS in either group was observed (p=0.12, p=0.13) due to reduction to QPB. We conclude that in patients with presumed advanced PC, reduction of the number of cores in PB may be an acceptable diagnostic strategy, but further studies are needed to analyze the impact of PB scheme reduction on other relevant pathological information obtained from PB.

PREOPERATIVE MODEL FOR PREDICTING PROSTATE SPECIFIC ANTIGEN RECURRENCE AFTER RADICAL PROSTATECTOMY USING PERCENT OF BIOPSY TISSUE WITH CANCER, BIOPSY GLEASON GRADE AND SERUM PROSTATE SPECIFIC ANTIGEN

PURPOSE

We developed a preoperative model to risk stratify patients for prostate specific antigen (PSA) failure following radical prostatectomy (RP) and identify those at high risk who would be potential candidates for neoadjuvant clinical trials.

MATERIALS AND METHODS

A retrospective survey of 459 patients from the SEARCH Database treated with RP between 1990 and 2002 was done. Multivariate analysis was used to compare the preoperative variables of patient age, race, PSA, biopsy Gleason score, clinical stage and percent of prostate needle biopsy tissue with cancer for the ability to predict time to PSA recurrence following RP. Significant independent predictors were combined to create a novel risk grouping model.

RESULTS

On multivariate analysis biopsy Gleason score (p < 0.001), percent of biopsy tissue with cancer (p < 0.001) and serum PSA (p = 0.001) were the only significant independent predictors of PSA failure. Combining these 3 significant predictors of PSA failure using previously published cutoff points for each variable generated a 4 tier preoperative model for predicting biochemical failure following RP (HR 1.91 for each 1 risk category increase, CI 1.62 to 2.26, p < 0.001). The model further stratified patients who were already stratified into low, intermediate and high risk groups based on a previously described model using PSA, biopsy Gleason score and clinical stage. A simplified table was developed to predict the risk of biochemical recurrence within 2 years following surgery, as stratified by percent of tissue with cancer, PSA and biopsy Gleason score.

CONCLUSIONS

A combination of serum PSA, biopsy Gleason score and percent of prostate biopsy tissue with cancer define a new preoperative model for predicting PSA failure following RP. This model further stratified patients who were already stratified based on PSA, biopsy Gleason score and clinical stage, and it can be used preoperatively to identify patients at high risk who would be candidates for neoadjuvant clinical trials. Using this model an easy to use table was developed to predict preoperatively the 2-year risk of PSA recurrence following RP.