Is one set of sextant biopsies enough to rule out prostate Cancer? Influence of transition and total prostate volumes on prostate cancer yield

Prostate-specific antigen density during dutasteride treatment for 1 year predicts the presence of prostate cancer in benign prostatic hyperplasia after the first negative biopsy (PREDICT study)

OBJECTIVES

To prospectively evaluate the detection rate of prostate cancer, and to identify the risk factors of prostate cancer detection after a 1-year administration of dutasteride and first negative prostate biopsy.

METHODS

Patients with benign prostatic hyperplasia who presented high prostate-specific antigen levels after the first negative prostate biopsy were administered 0.5 mg dutasteride daily for 1 year. They underwent a repeat prostate biopsy after 1 year. The primary end-point was the detection rate of prostate cancer. The secondary end-point was the ability of prostate-specific antigen kinetics to predict prostate cancer detection. Prostate-specific antigen was measured before the initial prostate biopsy and at 6, 9 and 12 months after starting dutasteride. Patients were classified into a prostate cancer and a non-prostate cancer group.

RESULTS

Prostate cancer was detected in 15 of 149 participants (10.1%). The total prostate-specific antigen change between the prostate cancer and non-prostate cancer group at 1 year was significantly different (P = 0.002). Although prostate-specific antigen levels at baseline did not significantly differ between study groups (P = 0.102), prostate-specific antigen levels at 6, 9 and 12 months were significantly different (P = 0.002, P = 0.001 and P < 0.001, respectively). The mean reduction rate of prostate-specific antigen density between the prostate cancer and non-prostate cancer group at 1 year was significantly different (-4.25 ± 76.5% vs -38.0 ± 28.7%, P = 0.001). Using a multivariate analysis, a >10% increase of prostate-specific antigen density at 1 year post-dutasteride treatment was the only predictive risk factor for prostate cancer after the first negative prostate biopsy (odds ratio 11.238, 95% confidence interval 3.112-40.577, P < 0.001).

CONCLUSION

In the present study cohort, >10% increase in prostate-specific antigen density represented the only significant predictive risk factor for prostate cancer diagnosis in patients with elevated prostate-specific antigen after the first negative prostate biopsy.

End-fire versus side-fire: a randomized controlled study of transrectal ultrasound guided biopsies for prostate cancer detection

Objectives: To compare prostate cancer detection rates between end-fire and side-fire ultrasound guided prostate biopsy techniques.Methods: A prospective randomized controlled trial was performed in patients who underwent prostate biopsy between 2009 and 2014. Patients were randomly assigned to the end-fire or side fire biopsy groups and underwent transrectal ultrasound guided prostate biopsy. The overall prostate cancer detection rate was compared between the two probe configurations. Trial was registered at Clinical Trials.gov with identifier: NCT00851292.Results: A total of 730 patients were included and randomized, 371 patients underwent prostate biopsy with side-fire probe and 359 patients with the end-fire probe. Prostate cancer detection rates were 52.4% in the end fire group and 45.6% in the side fire group (p = .066).Conclusions: No significant difference was found in detection rate of prostate cancer between the end-fire and side-fire probe in transrectal ultrasound guided prostate biopsy, neither for detection rate of prostate cancer in the apex.

Magnetic Resonance Spectroscopy and its Clinical Applications: A Review

In vivo NMR spectroscopy is known as magnetic resonance spectroscopy (MRS). MRS has been applied as both a research and a clinical tool in order to detect visible or nonvisible abnormalities. The adaptability of MRS allows a technique that can probe a wide variety of metabolic uses across different tissues. Although MRS is mostly applied for brain tissue, it can be used for detection, localization, staging, tumour aggressiveness evaluation, and tumour response assessment of breast, prostate, hepatic, and other cancers. In this article, the medical applications of MRS in the brain, including tumours, neural and psychiatric disorder studies, breast, prostate, hepatic, gastrointestinal, and genitourinary investigations have been reviewed.

Prostate-specific Antigen Density Variation Rate as a Potential Guideline Parameter for Second Prostate Cancer Detection Biopsy

Background:

The diagnostic value of current prostate-specific antigen (PSA) tests is challenged by the poor detection rate of prostate cancer (PCa) in repeat prostate biopsy. In this study, we proposed a novel PSA-related parameter named PSA density variation rate (PSADVR) and designed a clinical trial to evaluate its potential diagnostic value for detecting PCa on a second prostate biopsy.

Methods:

Data from 184 males who underwent second ultrasound-guided prostate biopsy 6 months after the first biopsy were included in the study. The subjects were divided into PCa and non-PCa groups according to the second biopsy pathological results. Prostate volume, PSA density (PSAD), free-total PSA ratio, and PSADVR were calculated according to corresponding formulas at the second biopsy. These parameters were compared using t-test or Mann-Whitney U-test between PCa and non-PCa groups, and receiver operating characteristic analysis were used to evaluate their predictability on PCa detection.

Results:

PCa was detected in 24 patients on the second biopsy. Mean values of PSA, PSAD, and PSADVR were greater in the PCa group than in the non-PCa group (8.39 μg/L vs. 7.16 μg/L, 0.20 vs. 0.16, 14.15% vs. −1.36%, respectively). PSADVR had the largest area under the curve, with 0.667 sensitivity and 0.824 specificity when the cutoff was 10%. The PCa detection rate was significantly greater in subjects with PSADVR >10% than PSADVR ≤10% (28.6% vs. 6.5%, P < 0.001). In addition, PSADVR was the only parameter in this study that showed a significant correlation with mid-to-high-risk PCa (r = 0.63, P = 0.03).

Conclusions:

Our results demonstrated that PSADVR improved the PCa detection rate on second biopsies, especially for mid-to-high-risk cancers requiring prompt treatment.

Analysis of topographical distribution of prostate cancer and related pathological findings in prostatectomy specimens using cMDX document architecture

INTRODUCTION

Understanding the topographical distribution of prostate cancer (PCa) foci is necessary to optimize the biopsy strategy. This study was done to develop a technical approach that facilitates the analysis of the topographical distribution of PCa foci and related pathological findings (i.e., Gleason score and foci dimensions) in prostatectomy specimens.

MATERIAL & METHODS

The topographical distribution of PCa foci and related pathologic evaluations were documented using the cMDX documentation system. The project was performed in three steps. First, we analyzed the document architecture of cMDX, including textual and graphical information. Second, we developed a data model supporting the topographic analysis of PCa foci and related pathologic parameters. Finally, we retrospectively evaluated the analysis model in 168 consecutive prostatectomy specimens of men diagnosed with PCa who underwent total prostate removal. The distribution of PCa foci were analyzed and visualized in a heat map. The color depth of the heat map was reduced to 6 colors representing the PCa foci frequencies, using an image posterization effect. We randomly defined 9 regions in which the frequency of PCa foci and related pathologic findings were estimated.

RESULTS

Evaluation of the spatial distribution of tumor foci according to Gleason score was enabled by using a filter function for the score, as defined by the user. PCa foci with Gleason score (Gls) 6 were identified in 67.3% of the patients, of which 55 (48.2%) also had PCa foci with Gls between 7 and 10. Of 1173 PCa foci, 557 had Gls 6, whereas 616 PCa foci had Gls>6. PCa foci with Gls 6 were mostly concentrated in the posterior part of the peripheral zone of the prostate, whereas PCa foci with Gls>6 extended toward the basal and anterior parts of the prostate. The mean size of PCa foci with Gls 6 was significantly lower than that of PCa with Gls>6 (P<0.0001).

CONCLUSION

The cMDX-based technical approach facilitates analysis of the topographical distribution of PCa foci and related pathologic findings in prostatectomy specimens.

Diagnostic Value of Different Systematic Prostate Biopsy Methods in the Detection of Prostate Cancer with Ultrasonographic Hypoechoic Lesions--A Comparative Study

OBJECTIVE

To assess if a less extended biopsy in the transperineal approach is sufficient for detection of prostate cancer (PC) in patients with hypoechoic lesions.

METHODS

This was a prospective study of 167 consecutive patients with prostate hypoechoic lesion and who underwent transperineal ultrasound (TPUS)-guided 12-core and hypoechoic lesion core biopsy between January 2012 and February 2013.

RESULTS

PC was detected in 64.1% (107/167) of patients. The PC detection rate of the 12-core prostate biopsy scheme was the highest, but when including the hypoechoic lesion core, there was no difference between the 6- and 12-core schemes (all p > 0.05), irrespective of prostate volume or prostate-specific antigen levels (all p > 0.05).

CONCLUSIONS

A more limited biopsy scheme could be sufficient for the detection of PC if the hypoechoic lesion is sampled.

Concordance between transrectal ultrasound guided biopsy results and radical prostatectomy final pathology: Are we getting better at predicting final pathology?

INTRODUCTION

Inaccuracy in biopsy Gleason scoring poses a risk to men who may then receive inappropriate treatment. We assess whether there was a change in discordance rates between biopsy and radical prostatectomy at our institution in recent years, while considering the implementation of active surveillance and the shift in biopsy scores caused by the 2005 International Society of Urologic Pathology update to the Gleason scoring protocol.

METHODS

We reviewed patients who underwent radical prostatectomy at our institution between May 2004 and April 2011. We analyzed clinical and pathological correlates of upgrading in 3 subgroups: Gleason sum (GS) 6/6, GS6/7 and GS7/7, where the sum preceding the dash was determined from biopsy and the subsequent sum was determined from the radical prostatectomy specimen. We applied the log-rank test and Cox model to a Kaplan Meier analysis of biochemical recurrence in the subgroups, and also mapped GS6/7 discordance over time.

RESULTS

In total, 1717 patients met our inclusion criteria. The 3 subgroups had significantly different mean prostate-specific antigen, patient age, tumour volume, margin status, pathologic stage, prostate weight, transrectal ultrasound volume and rate of progression (p < 0.05). We noted a multiphasic trend with a fall in discordance after 2005. However, there was no sustained trend over the study period taken as a whole (p = 0.06).

CONCLUSIONS

Although no sustained trend was observed, the falling discordance after 2005 may reflect the accommodation to the Gleason scoring update, while the gradual adoption of active surveillance may have led to the otherwise increasing trends. However, our observations may also be spurious biopsy sampling errors.

[Repeat prostate biopsies following a first negative biopsy in a context of an elevated prostate specific antigen]

INTRODUCTION

An elevated PSA and a negative prostate biopsy (PB) can be a false negative PB that ignores a prostate cancer (PCa) or a false positive PSA not related to PCa. The objective of this study was to analyze a group of patients who had a negative first BP for a PSA superior to 4 ng/mL and at least one additional PB and to compare these cases with controls who had the diagnosis PCa from the first PB.

METHODS

Retrospective single-center study comparing patients with an elevated PSA and repeat biopsy following a first negative PB and patients with PCa diagnosed from the first PB.

RESULTS

The 63 cases were younger than the 75 controls and had more often a normal digital rectal examination. Their prostate volume was larger and their number of PSA before the first PB lower: this corresponded to a lower PSA in the second (7/64), third (6/31), fourth (3/9) and sixth (1/1) PB. Among these cases with PCa, the length of core invaded by cancer and the total length of cancer of the entire PB were smaller than controls. In 76% of cases, the Gleason score among cases was 6 or less.

CONCLUSION

PCa discovered on repeat biopsy had features of better prognosis than those of controls. We propose an algorithm for management of patients with elevated PSA and negative first PB.

The absence of voiding symptoms in men with a prostate-specific antigen (PSA) concentration of ≥3.0 ng/mL is an independent risk factor for prostate cancer: results from the Gothenburg Randomized Screening Trial

What's known on the subject? and What does the study add? There are only a few studies and no consensus concerning the relationship between LUTS and prostate cancer. This paper focuses on 2353 men with an elevated PSA level within the Gothenburg Randomized Screening Trial who underwent biopsy and answered questions regarding LUTS. The main conclusion was that the absence of voiding symptoms is an independent risk factor for prostate cancer detection.

OBJECTIVE

To investigate whether men with obstructive voiding symptoms are at increased risk for being diagnosed with prostate cancer within the Gothenburg randomized population-based prostate cancer screening trial.

SUBJECTS AND METHODS

In 1995, 20 000 men born between 1930 and 1944 were randomly selected from the population register and randomized to either a screening group (10 000), invited for total prostate-specific antigen (tPSA) testing every second year until they reached an upper age-limit pending between 67 and 71 years, or to a control group not invited (10 000). Men with a PSA concentration of ≥3.0 ng/mL were offered further examination with prostate biopsies. Immediately before the physician's examination a self-administered, study-specific questionnaire was completed including one question concerning obstructive voiding symptoms. Multivariate logistic regression modelling was used to estimate odds ratios (ORs) for associations of age, tPSA, free/total PSA (f/tPSA) ratio, prostate volume and the presence of voiding symptoms in prostate cancer risk. A P < 0.05 was considered statistically significant.

RESULTS

Between 1995 and 2010 there were 2590 men who had an elevated PSA concentration (≥3.0 ng/mL) at least once during the study. Of these, 2353 men (91%) accepted further clinical examination with transrectal ultrasonography (TRUS) and prostate biopsies. In all, 633/2353 men had prostate cancer (27%) on biopsy and 1720/2353 men (73%) had a benign pathology. Men with prostate cancer reported a lower frequency of voiding symptoms (24% vs 31%, P < 0.001), independent of age and locally advanced tumours (T2b-T4). In the multivariate logistic regression model increasing age and tPSA were positively associated with prostate cancer while prostate volume, f/tPSA ratio and the presence of voiding symptoms were all inversely associated with the risk of detecting prostate cancer in a screening setting. This inverse association of voiding symptoms and prostate cancer detection was restricted to men with large prostates (>37.8 mL); 15% in men with voiding symptoms vs 22% in asymptomatic men (P < 0.001).

CONCLUSION

The presence of voiding symptoms should not be a decision tool for deciding which men with an elevated PSA concentration should be offered biopsies of the prostate.

Significance of atypical small acinar proliferation and high-grade prostatic intraepithelial neoplasia in prostate biopsy

Purpose

In clinical practice, atypical small acinar proliferation (ASAP) and high-grade prostatic intraepithelial neoplasia (HGPIN) are two common findings on prostate biopsies. Knowing the frequency of a prostate cancer diagnosis on repeat biopsies would aid primary treating physicians regarding their decisions in suspicious cases.

Materials and Methods

One hundred forty-three patients in whom biopsies revealed ASAP or HGPIN or both were enrolled in the present study; prostate cancer was not reported in the biopsy specimens and at least one repeat biopsy was performed. Age, digital rectal examination findings, prostate volumes, and free and total prostate-specific antigen (PSA) levels and the biopsy results of the patients were recorded.

Results

Of the 97 patients with ASAP on the first set of biopsies, prostate cancer was diagnosed in the second and third biopsies of 32 and 6 patients, respectively. Prostate cancer was not detected in the second or third biopsies of the 40 patients with HGPIN in the first biopsy. Of the 6 patients with ASAP+HGPIN in the first biopsy, prostate cancer was detected in 3 patients in the second biopsy and in 1 patient in the third biopsy.

Conclusions

The diagnosis of ASAP is a strong risk factor for prostate cancer. A repeat biopsy should be performed for the entire prostate subsequent to the diagnosis of ASAP. In patients with HGPIN according to the biopsy result, the clinical decision should be based on other parameters, such as PSA values and rectal examination, and a repeat biopsy should be avoided if the initial biopsy was performed with multiple sampling.

Accuracy of MRI/MRSI-based transrectal ultrasound biopsy in peripheral and transition zones of the prostate gland in patients with prior negative biopsy

The purpose of the study was to evaluate the accuracy of transrectal ultrasound biopsy (TRUS-biopsy) performed on regions with abnormal MRI and/or MRSI for both the transition (TZ) and the peripheral (PZ) zones in patients with suspected prostate cancer with prior negative biopsy, and to analyze the relationship between MRSI and histopathological findings. MRI and MRSI were performed in 54 patients (mean age: 63.9 years, mean PSA value: 11.4 ng/mL) and the ability of MRI/MRSI-directed TRUS biopsy was evaluated. A three-point score system was used for both techniques to distinguish healthy from malignant regions. Descriptive statistics and ROC analyses were performed to evaluate the accuracy and the best cut-off in the three-point score system. Twenty-two out of 54 patients presented cancer at MRI/MRSI-directed TRUS biopsy, nine presented cancer only in PZ, eight both in PZ and TZ, and five exclusively in TZ. On a patient basis the highest accuracy was obtained by assigning malignancy on a positive finding with MRSI and MRI even though it was not significantly greater than that obtained using MRI alone (area under the ROC curve, AUC: 0.723 vs 0.676). On a regional (n = 648) basis the best accuracy was also obtained by considering positive both MRSI and MRI for PZ (0.768) and TZ (0.822). MRSI was false positive in 11.9% of the regions. Twenty-eight percent of cores with prostatitis were false positive findings on MRSI, whereas only 2.7% of benign prostatic hyperplasia was false positive. In conclusion, the accuracy of MRI/MRSI-directed biopsies in localization of prostate cancer is good in patient (0.723) and region analyses (0.768). The combination of both MRI and MRSI results makes TRUS-biopsy more accurate, particularly in the TZ (0.822) for patients with prior negative biopsies. Histopathological analysis showed that the main limitation of MRSI is the percentage of false positive findings due to prostatitis.

Mechanically assisted 3D ultrasound guided prostate biopsy system

There are currently limitations associated with the prostate biopsy procedure, which is the most commonly used method for a definitive diagnosis of prostate cancer. With the use of two-dimensional (2D) transrectal ultrasound (TRUS) for needle-guidance in this procedure, the physician has restricted anatomical reference points for guiding the needle to target sites. Further, any motion of the physician's hand during the procedure may cause the prostate to move or deform to a prohibitive extent. These variations make it difficult to establish a consistent reference frame for guiding a needle. We have developed a 3D navigation system for prostate biopsy, which addresses these shortcomings. This system is composed of a 3D US imaging subsystem and a passive mechanical arm to minimize prostate motion. To validate our prototype, a series of experiments were performed on prostate phantoms. The 3D scan of the string phantom produced minimal geometric distortions, and the geometric error of the 3D imaging subsystem was 0.37 mm. The accuracy of 3D prostate segmentation was determined by comparing the known volume in a certified phantom to a reconstructed volume generated by our system and was shown to estimate the volume with less then 5% error. Biopsy needle guidance accuracy tests in agar prostate phantoms showed that the mean error was 2.1 mm and the 3D location of the biopsy core was recorded with a mean error of 1.8 mm. In this paper, we describe the mechanical design and validation of the prototype system using an in vitro prostate phantom. Preliminary results from an ongoing clinical trial show that prostate motion is small with an in-plane displacement of less than 1 mm during the biopsy procedure.

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

The influence of prostate volume on prostate cancer detection using a combined approach of contrast-enhanced ultrasonography-targeted and systematic grey-scale biopsy

OBJECTIVE

To evaluate the influence of prostate volume (PV) on the detection of prostate cancer using a combined approach of contrast-enhanced ultrasonography (CEUS) and grey-scale US-guided systematic biopsy (SB).

PATIENTS AND METHODS

We evaluated 345 patients with prostate cancer and a total prostate-specific antigen (PSA) level of >/= 1.32 ng/mL (1.32-35.3, mean 6.6). Biopsies were taken by two independent examiners; one took five CEUS (Doppler) targeted biopsies of hypervascular regions in the peripheral zone, and subsequently the other took 10 systematic prostate biopsies. We assessed the cancer detection rates for the five different subgroups of prostate volumes, i.e. <20, 20-30, 30-40, 40-50 and > 50 mL.

RESULTS

Each technique, SB and CEUS, detected 73.4% and 77.1% of all detected cancers, respectively, but there were statistically significant differences in detection rate only in small glands. Only 69.0% and 70.4% of all cancers were detected by SB in glands of <20 and 20-30 mL, respectively, whereas 88.1% and 80.8% were detected by CEUS.

CONCLUSION

The prostate cancer detection rate for CEUS was significantly higher in prostates of <30 mL (48.1% of the study population) than for SB. Therefore the combined approach of CEUS and SB allows improved cancer detection in patients with small glands and low total PSA values.

Biopsy standards for detection of prostate cancer

The widespread use of measurement of prostate-specific antigen for prostate cancer screening has led to a dramatic increase in the number of transrectal biopsies. Although transrectal ultrasound-guided prostate biopsy is the gold standard in the diagnosis of prostate cancer, the strategies for initial and repeat biopsies remain controversial. Over the past decade numerous biopsy protocols have been developed. Several protocols have been established that increase the number of cores by combining sextant and lateral biopsies to increase the cancer detection rate. We review the current methods of prostate biopsies, the indication to perform an initial and repeat biopsy, the impact of prostate volume on the number of cores taken, and the morbidity of the procedure.

The effects of 5alpha-reductase inhibitors on the natural history, detection and grading of prostate cancer: current state of knowledge

PURPOSE

The Prostate Cancer Prevention Trial (PCPT) showed that the 5alpha-reductase inhibitor (5ARI) finasteride significantly decreased the 7-year period prevalence of prostate cancer vs placebo. However, Gleason score 7-10 tumors were significantly more common in the finasteride vs the placebo group. We considered data on the effects of 5ARIs on prostate cancer natural history and detection.

MATERIALS AND METHODS

A detailed review was performed of the literature identified from the MEDLINE database examining the effects of 5ARIs on prostate cancer prevalence and tumor histopathology.

RESULTS

In PCPT there were fewer biopsies performed for cause in the finasteride vs the placebo group and the proportion of high grade tumors in the treatment groups did not diverge with time. Given that finasteride has an effect on prostate specific antigen and prostate volume, which are key factors in triggering prostate biopsies, they may be significant confounders of Gleason score results. Prostate shrinkage in the finasteride treated group may minimize biopsy sampling error. Furthermore, histological studies have shown that 5ARIs have a significant effect on prostate architecture, which can make the interpretation of prostate specimens in men treated with 5ARIs difficult. Further evaluation of PCPT findings will help determine the true nature of these observations.

CONCLUSIONS

5ARIs decrease the risk of prostate cancer but also alter the detection of disease through effects on prostate specific antigen, and prostate volume and histology. The weight of evidence suggests an artifactual effect of finasteride on Gleason grading in the PCPT. The role of 5ARIs for prostate cancer chemoprevention needs further examination before it can be considered for wide recommendation.

Determinants for Prediction of Malignant Potential by Metalloproteinase:E-Cadherin Ratio in Prostate Core Needle Biopsy

According to a good correlation between in situ hybridization-based metalloproteinase-2/9:E-cadherin ratio (MER) and the pathological stage of prostate cancer, we set the cutoff line of MER at 6.0 (MER>6) to distinguish between organ-confined (pT2) and advanced diseases (pT3a-b/N1). In this study, we looked at the factors affecting MER and leading to a misprediction of the pathological stage. We examined MER in 39 paired specimens of prostate core needle biopsy and prostatectomy from the same patient and compared these MERs. In 34 (87%) of 39 cases, the MER of biopsy was correlated with the final pathological stage (pT2 vs. pT3a-b/N1). MER ranges in pT3a-b/N1 cancer were significantly wider than those in pT2 cancer (p < 0.01). The number of MER>6 fields in Gleason score 8-9 cancer was larger than that in Gleason score 7 cancer (p < 0.0001). In 5 cases where there was a failure to distinguish pT2 from pT3a-b/N1, the misdiagnosis was significantly associated with a small number of biopsies (4 or 6 specimens; p = 0.0469), a small amount of tumor tissue in biopsy specimens (less than 5 mm; p = 0.0492), and a wide MER range (more than 5.0; high intratumoral heterogeneity; p = 0.0202). Considering these factors increases the usefulness of preoperative prediction of the final pathological stage by MER in prostate cancer.

The impact of a suspicious prostate biopsy on patients' psychological, socio-behavioral, and medical care outcomes

OBJECTIVE

To evaluate the psychological, socio-behavioral, and medical implications of apparently false-positive prostate cancer screening results.

METHODS

One hundred and twenty-one men with a benign prostate biopsy performed in response to a suspicious screening test (biopsy group) and 164 men with a normal prostate-specific antigen (PSA) test result (normal PSA group) responded to a questionnaire 6 weeks, 6 and 12 months after their biopsy or PSA test.

RESULTS

The mean (+/-SD) age of respondents was 61+/-9 years (range, 41 to 88 years). One year later, 26% (32/121) of men in the biopsy group reported having worried "a lot" or "some of the time" that they may develop prostate cancer, compared with 6% (10/164) in the normal PSA group (P<.001). Forty-six percent of the biopsy group reported thinking their wife or significant other was concerned about prostate cancer, versus 14% in the normal PSA group (P<.001). Medical record review showed that biopsied men were more likely than those in the normal PSA group to have had at least 1 follow-up PSA test over the year (73% vs 42%, P<.001), more likely to have had another biopsy (15% vs 1%, P<.001), and more likely to have visited a urologist (71% vs 13%, P<.001).

CONCLUSION

One year later, men who underwent prostate biopsy more often reported worrying about prostate cancer. In addition, there were related psychological, socio-behavioral, and medical care implications. These hidden tolls associated with screening should be considered in the discussion about the benefits and risks of prostate cancer screening.

Standardization of transrectal ultrasound-guided biopsy

Ultrasound-guided biopsy is more sensitive to biopsy performed under the digital control, because 29% of prostatic cancers are not palpable. On the other hand, at least 30% of cancers are isoechogenic, so they cannot be viewed by transrectal ultrasound examination. It means that target biopsy is not sufficient for diagnosis of localized prostatic cancer, i.e., randomized samples are needed as well. More than ten years ago, the technique of sampling the six specimens became a standard procedure to which previously harvested target specimens from suspected growths were added. Today, the expansion of biopsy protocol is recommended, by obtaining the additional specimens from peripheral lateral area, four plus two samples if the prostate has volume over 50 ml. Larger number of biopsies requires anesthesia. In order to reduce complication, the cleaning of rectal ampulla and prophylactic use of quinolone are suggested.

Current status of transrectal ultrasound-guided prostate biopsy in the diagnosis of prostate cancer

In contemporary practice, most prostate cancers are either invisible on ultrasound or indistinguishable from concurrent benign prostatic hyperplasia. Diagnosis therefore rests on prostate biopsy. Biopsies are not simply directed at ultrasonically visible lesions, as these would miss many cancers; rather the whole gland is sampled. The sampling itself is systematic, using patterns based on prostate zonal anatomy and the geographical distribution and frequency of cancer. This review explains the evolution of the prostate biopsy technique, from the classical sextant biopsy method to the more recent extended biopsy protocols (8, 10, 12, >12 and saturation biopsy protocols). Extended protocols are increasingly being used to improve diagnostic accuracy, especially in those patients who require repeat biopsy. This trend has been facilitated by the ongoing improvement in safety and acceptability of the procedure, particularly with the use of antibiotic prophylaxis and local anaesthesia. The technical details of these extended protocols are discussed, as are the current data regarding procedure-related morbidity and how this may be minimized.

The Potential Impact of Prostate Volume in the Planning of Optimal Number of Cores in the Systematic Transperineal Prostate Biopsy

OBJECTIVES

We compared the detection rates of different transperineal prostate biopsy protocols with the aim to optimize the number of cores to sample according to prostate volume.

MATERIAL AND METHODS

From October 2002 to October 2004 we evaluated 480 consecutive patients with PSA between 2.5 and 20 ng/ml undergoing the first set of prostate biopsy. All patients underwent a 14-core TRUS-guided transperineal prostate biopsy, including 12 cores in the peripheral and two in the transitional zone. The detection rate of the 14-core scheme was compared to the one of the other biopsy schemes obtained through the exclusion of pairs of cores. Data were stratified according to the different TRUS estimated prostate volumes.

RESULTS

The detection rate of the standard sextant was 35.2%, while those of the 8-core schemes ranged from 37.1 to 38.8%. The 10-core schemes yielded detection rates of 39.6-40.8% and the protocol with 12 biopsies in the peripheral zone diagnosed prostate cancer in 42.1% of the patients. In patients with <30 cc prostate volume, the detection rate of the 14-core scheme was 43.8% and resulted statistically overlapping to the 8-peripheral cores protocol. In patients with 30.1-50 cc prostate volume a 12-peripheral core biopsy reproduced the results of the 14-core sampling. In prostates larger than 50 cc, an even more extensive procedure was mandatory, considering the low detection rate of the 14-core scheme (24.2%).

CONCLUSION

Transperineal prostate biopsy is a safe procedure with a very low complication rate and high cancer detection rate. Prostate volume is the most relevant variable in the planning of the optimal number of cores in the extensive first biopsy set. A protocol with more than 8 peripheral cores) is recommended only in patients with prostate volume larger than 30 cc.

Are Transition Zone Biopsies Still Necessary to Improve Prostate Cancer Detection?

OBJECTIVES

The present retrospective study was designed to investigate the value of transition zone (TZ) biopsies for prostate cancer (PC) detection rate in a combined contrast enhanced color Doppler targeted (CECD) and gray-scale systematic biopsy (SB) approach.

METHODS

PSA screening participants totalling 1475 with tPSA of >1.25 ng/ml (fPSA< or =18%) were assessed. Ten SB and additionally 5 or fewer CECD were performed. The impact of TZ biopsies on the PC detection rate and the biological significance of the detected TZ-cancers were analyzed.

RESULTS

Out of 1475 biopsied patients, 395 (26.8%) were identified as PC patients; 5925 biopsy cores from these patients were analyzed. In 86 patients (21.8% of PC), we found 102 PC- positive cores in the TZ, and only in 9 of them solitary TZ-cancers without any other PC-location (2.3% of PC or 0.6% of all investigated patients). Pathologic findings after retropubic prostatectomy (RPE) revealed multifocal adenocarcinoma including involved peripheral zone (PZ) in eight of these nine patients, and solitary TZ-cancer in one patient. There was no positive correlation between prostate volume and TZ-detection rate and no patient with solitary TZ-PC after rebiopsy.

CONCLUSION

Biopsy revealed 9 solitary TZ cancers (1.8%) and RPE revealed only one of them to be truly TZ-confined cancer (0.6%). Furthermore PC-detection did not improve, even in patients with rebiopsy, and there was no correlation between detection of TZ-cancers and prostate volume. A combined use of CECD and SB to investigate participants of a PSA-screening program suggests that TZ-biopsies do not improve PC detection rate and are therefore unnecessary.

[Use of 5-alpha-reductase inhibitors in the prevention of prostate cancer]

5-alpha-reductase inhibitors are now in widespread use for the treatment of benign prostatic hyperplasia (BHP) and these molecules have recently come under the spotlight in prostate cancer. Their peripheral "hormonal" action inducing reduced intraprostatic DHT synthesis seems to involve them in this hormone-dependant disorder. Finasteride evaluated in the treatment of BPH (PLESS study) was found to have a preventive effect on the incidence of cancer and this activity was assessed in a specific trial (PCPT study). Nevertheless, in the latter randomized study with a 7-year follow-up period, a reduction in the global incidence of the number of cases of cancers was associated with an increase in the number of high-grade cancers. A slight reduction in prostate cancer was also noted in the studies with dutasteride in BPH (ARIA3001, ARIA3002 and ARIB3003). An international multicenter study (REDUCE) is currently being conducted to confirm the preventive value of this molecule which has a more complete activity than finasteride with its inhibitory action on the two 5-alpha-reductase iso-enzymes, and may therefore have a clearer efficiency and rule out the risk of onset of high-grade cancer.

Psychological effects of a suspicious prostate cancer screening test followed by a benign biopsy result

PURPOSE

To evaluate the psychological implications of an apparently false-positive screening result for prostate cancer.

METHODS

The sample comprised 167 men with a benign biopsy result in response to a suspicious screening test result (biopsy group) and 233 men with a normal prostate-specific antigen (PSA) test result (control group). The men responded to a questionnaire within about 6 weeks of their biopsy or PSA results. They were asked about demographic characteristics, medical history, psychological effects, biopsy experience, and prostate cancer knowledge.

RESULTS

The survey response rate was 85% (400/471). The mean (+/- SD) age of respondents was 60 +/- 9 years (range, 40 to 88 years); 88% (n = 350) were white. Forty-nine percent (81/167) of men in the biopsy group reported having thought about prostate cancer either "a lot" or "some of the time", compared with 18% (42/230) in the control group (P < 0.001). In addition, 40% (67/167) in the biopsy group reported having worried "a lot" or "some of the time" that they may develop prostate cancer, compared with 8% (18/231) in the control group (P < 0.001).

CONCLUSION

Men who underwent prostate biopsy more often reported having thought and worried about prostate cancer, despite having received a benign result. This underrecognized human cost of screening should be considered in the debate about the benefits and harms of prostate cancer screening.

Clinical, biochemical and pathological features of initial and repeat transrectal ultrasonography prostate biopsy positive patients

BACKGROUND

Using sextant biopsy, 16-41% of prostate cancers were diagnosed on repeat biopsy. The objective of the present study was to compare the differences in the clinical, biochemical and pathological features between patients with positive results on initial and repeat biopsies, with an aim to identify factors that can be used to improve the detection rate of transrectal ultrasound (TRUS) biopsy of the prostate.

METHODS

Between February 2000 and April 2001, 222 patients with a mean age of 64 years (range 38-85) underwent TRUS-guided 10-core prostate biopsy for either abnormal prostate specific antigen (PSA) levels (>4 ng/mL) and/or abnormal digital rectal examination (DRE). Of this number, 165 patients underwent their first biopsy, whereas 45 and 12 patients had had one or two previous biopsies, respectively.

RESULTS

Prostate cancer detection rates for the initial biopsy group (n = 165), second biopsy group (n = 45) and third biopsy group (n = 12) were 29.7, 23.0 and 41.7%, respectively. Six patients who had a negative first 10-core biopsy underwent a second 10-core biopsy and one patient (16%) was found to have cancer. Apart from total prostate volume, there were no significant statistical differences between the patient age, mean total PSA, PSA density, PSA-transition zone density, DRE and TRUS findings between the initial and repeat biopsy groups of subjects who had cancer. Those who had cancer detected only on repeat biopsies had larger prostate glands (P = 0.041).

CONCLUSION

Patients who had cancer detected only on repeat biopsies had bigger prostate glands, supporting the hypothesis that TRUS sextant biopsy as a technique suffers the error of under-sampling in a bigger prostate.

Effect of dutasteride on the detection of prostate cancer in men with benign prostatic hyperplasia

OBJECTIVES

To examine the rate of prostate cancer detection in three large randomized placebo-controlled benign prostatic hyperplasia trials of dutasteride. Dutasteride, which lowers serum dihydrotestosterone more than 93% by inhibiting type 1 and type 2 5-alpha-reductase, is effective in the treatment of benign prostatic hyperplasia. However, its effect on the development of prostate cancer is unknown.

METHODS

A total of 4325 men with benign prostatic hyperplasia but without a history, or evidence, of prostate cancer, and a serum prostate-specific antigen level of 1.5 to 10 ng/mL, were randomized to 0.5 mg/day dutasteride or placebo for 24 months. The prostate cancer detection rates for subjects were determined by non-protocol-mandated biopsies, either during the double-blind phase of the study or during the first 3 months of the open-label extension. A follow-up questionnaire was administered to a subset of consenting subjects to ascertain the number, outcomes, and reasons for the prostate biopsies.

RESULTS

The cumulative incidence of prostate cancer as an adverse event was significantly lower in the dutasteride versus placebo group at 24 months (1.1% versus 1.9%, P = 0.025) and 27 months (1.2% versus 2.5%, P = 0.002). There were no differences in the diagnosis rates of prostate cancer during the first 15 months, after which time the detection rate of prostate cancer increased in the placebo group and remained low in the dutasteride group.

CONCLUSIONS

Prostate cancer detection was significantly lower in subjects randomized to dutasteride compared with the placebo group. These results have prompted the initiation of the Reduction by Dutasteride of Prostate Cancer Events (REDUCE) study, which was designed and powered to test the hypothesis that treatment with dutasteride decreases the incidence and progression of prostate cancer.

No reason for immediate repeat sextant biopsy after negative initial sextant biopsy in men with PSA level of 4.0 ng/mL or greater (ERSPC, Rotterdam)

OBJECTIVES

In the early detection of prostate cancer (CaP) uncertainty exists concerning the most appropriate biopsy procedure. Within the European Randomized Study of Screening for Prostate Cancer (ERSPC) lateralized sextant biopsies are used. False-negative results of sextant biopsies have led to the extensive use of procedures using 12 or more biopsy cores. The ERSPC offers the opportunity to study the yield of repeat biopsies after 4 years in men who had negative sextant biopsies and a prostate-specific antigen (PSA) level of 4.0 mg/mL or more at the first screening round.

METHODS

Between August 1996 and May 1998, a total of 6876 men (age 55 to 74 years) were randomized to the screening arm and actually underwent screening. The numbers and levels of biopsy indicators, as well as possible predictors for biopsy outcome, in the second screening round, such as prostate volume, volume change over time, prostate-specific antigen density (PSAD), PSA velocity, and age, were calculated and compared for participants with positive and negative biopsies in round 2. The positive predictive value (PPV) and detection rates, as well as parameters of aggressiveness, were evaluated for second-round biopsy-detected and interval CaP cases.

RESULTS

Of the 728 men with a PSA level of 4.0 mg/mL or more who underwent biopsy at initial screening, 553 were eligible for a second screening visit after 4 years. Of these, 272 (49.2%) actually underwent screening. Eighteen CaP cases were detected with 217 biopsies, indicated by a PSA level of 3.0 ng/mL or more (PPV 8.3%). Eight interval cases were identified by linking to the Cancer Registry. These 26 cases would have increased the PPV and detection rate of the initial screening round from 36.1% to 39.7% and from 3.8% to 4.2%, respectively. Most of these cases (23 of 26 or 88.5%) were organ confined and amenable to potentially curative treatment.

CONCLUSIONS

Although the results of this study may have been biased by the low rate of availability/eligibility of participants for rescreening (after 4 years), the proportion of cancers detected after a previous lateral sextant biopsy indicated by a PSA value of 4.0 mg/mL or more (PPV 8.3%) fell far short of the overall PPV at rescreening (PPV 20%). The features of most cancers that were possibly missed during the first round allowed a potentially curative approach. The ERSPC study group found no reason to change the ERSPC protocol.

Clinical and pathologic features of prostate cancer detected after repeat false-negative biopsy in a screening population

BACKGROUND

The present study was designed to investigate whether the clinical or pathologic features of prostate cancer (PCa) are related to the number of repeat biopsies required to establish the diagnosis of PCa.

METHODS

Between February 1993 and August 2000, 653 patients were evaluated in this retrospective study. All patients underwent transrectal ultrasound-guided biopsy of the prostate prior to radical retropubic prostatectomy. The pathologic findings of specimens obtained at radical prostatectomy and pelvic lymph node dissection as well as PSA levels, findings on DRE, prostate volumes, transition zone volumes, and age were analyzed separately for all PCa patients diagnosed at the first set of biopsies (group A) and compared with the data of those diagnosed at the 2nd-5th set of biopsies (group B). In a second step, we compared the results obtained from patients diagnosed at the 2nd set of biopsies (group B1) with those of patients diagnosed at the 3rd to 5th set of biopsies (group B2).

RESULTS

Gleason scores, pathologic tumor stages, and tumor volumes in group B were found to be significantly decreased compared to group A. But from the 2nd to 5th serial biopsy no further decrease in pathologic stage, Gleason score, or tumor volume was observed. On the contrary, there was a tendency towards higher tumor stages and Gleason scores. Of the tumors detected after the second false-negative set of biopsies almost 70% were lesions with Gleason scores of 6 or higher.

CONCLUSIONS

False-negative results at the first needle biopsy are predictive of a lower pathologic stage and grade as well as smaller tumor volumes of PCa diagnosed at repeat sets of biopsies. False-negative results on repeat biopsy, however, have no prognostic significance for the tumor stage of PCas detected at subsequent sets of biopsies.

When to biopsy and when to stop biopsying

With the widespread use of serum prostate-specific antigen (PSA) and transrectal ultrasound-guided needle biopsy of the prostate in men with suspected prostate cancer, physicians are faced with the dilemma of treating a patient with a high index of suspicion of prostate cancer but with an initial set of negative biopsies. For the initial biopsy, the optimal number of biopsy cores for detecting prostate cancer in prostate biopsy remains controversial; it is also often unclear who should undergo a repeat prostatebiopsy and when to stop biopsying.

Can total and transition zone volume of the prostate determine whether to perform a repeat biopsy?

OBJECTIVES

To compare the ability of total prostate (TP) and transition zone (TZ) volume to predict the outcome of a repeat prostate biopsy in patients with serum prostate-specific antigen (PSA) levels of 4 to 10 ng/mL.

METHODS

A total of 1137 patients were included and underwent transrectal ultrasound-guided needle sextant and two transition zone biopsies of the prostate. All patients with a prior negative biopsy (benign prostatic tissue) underwent a repeat biopsy after 6 weeks. The TP and TZ volumes of the prostate were measured by transrectal ultrasonography.

RESULTS

Of the 1137 patients, prostate cancer was diagnosed in 364 (32%), in 276 (24.2%) after the first biopsy and in 88 (7.7%) after the repeated biopsy. The TP and TZ volumes were larger in the patients with prostate cancer detected on the repeated biopsy (P <0.0001). Using a cutoff for TP volume of less than 20 cm3 and greater than 80 cm3 and for TZ volume of less than 9 cm3 and greater than 41 cm3 would have spared 7.1% and 10% of repeated biopsies, respectively.

CONCLUSIONS

The probability for a positive repeat prostate biopsy increases in a logarithmic function for larger prostates, as well as for larger TP and, especially, for larger TZ volumes. The probability of finding prostate cancer on a repeat biopsy in prostates with small (less than 20 cm3) and large (greater than 79 cm3) TP, as well as in small (less than 9.3 cm3) and large (greater than 41 cm3) TZ volumes, was very low. Therefore, a repeat prostate biopsy within 6 weeks is unnecessary. These patients should be followed up by serial PSA determination.

The diagnostic accuracy of the age-adjusted and prostate volume-adjusted biopsy method in males with prostate specific antigen levels of 4.1-10.0 ng/mL

BACKGROUND

The authors evaluated a new age-adjusted and prostate volume-adjusted biopsy method for the detection of prostate carcinoma through the transperineal and the transrectal approaches in men with PSA levels of 4.1-10.0 ng/mL.

METHODS

The value of the adjusted biopsy method was calculated by using the following four factors: 1) life expectancy in Japanese men in 1998, 2) prostate volume estimated by transrectal ultrasonography, 3) tumor doubling time (4 years), and 4) tumor volume that influenced death (20 cc). The number of biopsy sites was set at 8-20. Between August, 1999 and December, 2001, 100 men age <or= 79 years with prostate specific antigen (PSA) levels of 4.1-10.0 ng/mL underwent age-adjusted and volume-adjusted, systematic prostate biopsy.

RESULTS

The detection rate for the adjusted biopsy method was 46% (46 of 100 men). The clinical stage of prostate carcinoma was Stage II in 85% of patients and Stage III in 15% of patients. If routine six-sextant biopsy had been performed in all of the men who underwent adjusted systematic biopsy, then 15 of 46 patients (33%) with prostate carcinoma would have been missed. The detection rates of prostate carcinoma in men who underwent adjusted biopsies were relatively high, especially in men with PSA levels of 6.1-10.0 ng/mL, men age <or= 64 years, men with prostate volumes >or= 50 cc, and men with PSA density (PSAD) levels <or= 0.15 ng/mL/cc compared with the detection rates from six-sextant and directed biopsies. The high detection rates were observed from biopsy sites at the posterior aspect of the lateral lobe through both the transperineal approach and the transrectal approach and at the anterior aspect of the transition zone through the transperineal approach.

CONCLUSIONS

The age-adjusted and prostate volume-adjusted prostate biopsy method was more useful for detecting clinically significant disease compared with the traditional six-sextant biopsy method. This adjusted biopsy method was especially useful in patients age <or= 64 years, patients with large prostate volumes (>/= 50 cc), and patients with PSAD levels <or= 0.15 ng/mL/cc. The authors recommend that patients undergo an additional transition zone biopsy at the anterior aspect through the transperineal approach.

Prostate: high-frequency Doppler US imaging for cancer detection

PURPOSE

To evaluate cancer detection with targeted biopsy of the prostate performed on the basis of high-frequency Doppler ultrasonographic (US) imaging findings versus cancer detection with a modified sextant biopsy approach with laterally directed cores.

MATERIALS AND METHODS

Sixty-two patients were prospectively evaluated with gray-scale, color, and power Doppler transrectal US performed with patients in the lithotomy position. Gray-scale and Doppler findings within each sextant were rated on a five-point scale. Up to four targeted biopsy specimens were obtained from each patient on the basis of Doppler findings; this was followed by a modified sextant biopsy. Conditional logistic regression analysis was performed to compare the positive yields for targeted and sextant biopsy specimens. Clustered receiver operating characteristic analysis was performed to compare gray-scale, color, and power Doppler detection of cancer at sextant biopsy sites.

RESULTS

Cancer was detected in 18 (29%) of 62 patients, including 11 patients in whom cancer was detected with both sextant and targeted biopsy, six in whom cancer was detected only with sextant biopsy, and one in whom cancer was detected only with targeted biopsy. The positive biopsy rate for targeted biopsy (24 [13%] of 185 cores) was slightly higher than that for sextant biopsy (36 [9.7%] of 372 cores; P =.1). The odds ratio for cancer detection with targeted versus sextant cores was 1.8 (95% CI: 0.9, 3.7). Receiver operating characteristic analysis demonstrated that overall identification of positive sextant biopsy sites was close to random chance for gray-scale (area under the curve, 0.53), color Doppler (area under the curve, 0.50), and power Doppler (area under the curve, 0.47) imaging.

CONCLUSION

Targeted biopsy performed on the basis of high-frequency color or power Doppler findings will miss a substantial number of cancers detected with sextant biopsy.

Repeat prostate biopsy: who, how and when? a review

Urologists are frequently faced with the dilemma of treating a patient with a high index of suspicion of prostate cancer (PCa), but an initial set of negative biopsies. In this review, we evaluated the current knowledge on repeat prostate biopsies, focusing on when to perform them and in which patients, how many samples to take, where to direct the biopsies and what morbidity should be expected. We focussed on the available literature and the multicenter European Prostate Cancer Detection (EPCD) study. The EPCD study included 1051 men with a total PSA from 4 to 10 ng/ml who underwent a transrectal ultrasound (TRUS) guided sextant biopsy and a repeat biopsy in case of a negative initial biopsy. Most studies support that increasing the number of biopsy cores as compared to the sextant technique and improving prostate peripheral zone (PZ) sampling result in a significant improvement in the detection of prostate cancer without increase in morbidity or effects on quality of life. Re-biopsy can be performed 6 weeks later with no significant difference in pain or morbidity. At least 10% of patients with negative sextant prostatic biopsy results in the EPCD study were diagnosed with PCa on repeat biopsy, percent free PSA and PSA density of the transition zone being the most accurate predictors. Despite differences in location (more apico-dorsal) and multifocality, pathological and biochemical features of cancers detected on initial and repeat biopsy were similar, suggesting similar biological behavior and thus advocating for a repeat prostate biopsy in case of a negative finding on initial biopsy. Indications and ideal number of biopsy cores to take when repeating biopsies in patients who already underwent extensive biopsy protocols on the first biopsy remains to be determined.

Biological selection criteria for radical prostatectomy

Tumors clinically confined to the prostate gland (T1-2) are heterogeneous with respect to pathological staging and outcome after definitive radical surgery (radical prostatectomy). The preoperative prognostic factors that could predict pathological stage and outcome of individual patients with clinically localized prostate cancer are reviewed. New preoperative factors have been identified by histological analysis of needle biopsy prostate specimens in addition to Gleason grading score, serum markers (PSA), and clinical staging. These factors are related to tumor volume, zonal origin of the tumor, and spread into the gland and surrounding tissues. Other biological factors are identified by molecular and immunohistochemical analysis (neuroendocrine differentiation, DNA content, microvessel density, and perineural invasion). Biomolecular factors can also be assessed preoperatively on serum samples (free/total PSA ratio, PSA RT-PCR). Although only a few of these factors have a role in predicting treatment failure and/or disease recurrence, the neural network analysis seems to be the most important tool for identifying patients with more aggressive disease. A combination of these new factors, also using neural networks, could be relevant in the preoperative management of patients with prostate cancer to identify those with confined disease and to select those suitable for a "nerve sparing radical prostatectomy" to preserve sexual function and to achieve definitive cancer control.

Does transurethral resection of the prostate facilitate detection of clinically significant prostate cancer that is missed with systematic sextant and transition zone biopsies?

BACKGROUND

A prospective study was conducted to determine whether transurethral resection of the prostate (TURP) facilitates detection of prostate cancer that is missed with systematic sextant biopsies associated with transition zone (TZ) biopsies.

METHODS

A total of 139 consecutive patients underwent transperineal TZ biopsies of each lobe in addition to a transrectal systematic sextant peripheral zone (PZ) biopsy. Patients whose biopsies were negative for cancer received TURP for relief of lower urinary tract obstruction when indicated.

RESULTS

Cancer was detected in biopsy specimens of 40 patients. Of these cancers, 18 originated in the PZ alone and 22 were located both in the TZ and the PZ. No cancers were detected in the TZ alone. Of 99 patients who were proven not to have cancer by the biopsies, 18 were indicated for TURP. Five of these patients (28%) had cancer in the resected tissues. All cancers were clinically organ confined and their Gleason sum scores were 2-5. Cancer-positive chips accounted for less than 10% of all resected specimens. Of the 66 patients with negative biopsies and without indication for TURP, four (6%) were revealed to have an elevation of the serum PSA level during follow up. They were later proven to have cancer by a second biopsy.

CONCLUSION

Routine use of TZ biopsy is not warranted for detection of cancer. Transurethral resection of the prostate can detect cancers in patients with negative PZ and TZ biopsies. However, cancers detected by TURP may not always be clinically significant and only four of 66 patients who were not indicated for TURP and received a close follow up were later found to have cancer, although their follow-up period was short. Thus, it still remains to be elucidated whether TURP is necessary for all patients with negative biopsies of the prostate.