Prostate cancer detection and tumor characteristics in men with multiple biopsy sessions

Reliability of Multiparametric Magnetic Resonance Imaging in Patients with a Previous Negative Biopsy: Comparison with Biopsy-Naïve Patients in the Detection of Clinically Significant Prostate Cancer

Background: Multiparametric magnetic resonance is an established imaging utilized in the diagnostic pathway of prostate cancer. The aim of this study is to evaluate the accuracy and reliability of multiparametric magnetic resonance imaging (mpMRI) in the detection of clinically significant prostate cancer, defined as Gleason Score ≥ 4 + 3 or a maximum cancer core length 6 mm or longer, in patients with a previous negative biopsy. Methods: The study was conducted as a retrospective observational study at the University of Naples "Federico II", Italy. Overall, 389 patients who underwent systematic and target prostate biopsy between January 2019 and July 2020 were involved and were divided into two groups: Group A, which included biopsy-naïve patients; Group B, which included re-biopsy patients. All mpMRI images were obtained using three Tesla instruments and were interpreted according to PIRADS (Prostate Imaging Reporting and Data System) version 2.0. Results: 327 patients were biopsy-naïve, while 62 belonged to the re-biopsy group. Both groups were comparable in terms of age, total PSA (prostate-specific antigen), and number of cores obtained at the biopsy. 2.2%, 8.8%, 36.1%, and 83.4% of, respectively, PIRADS 2, 3, 4, and 5 biopsy-naïve patients reported a clinically significant prostate cancer compared to 0%, 14.3%, 39%, and 66.6% of re-biopsy patients (p < 0.0001-p = 0.040). No difference was reported in terms of post-biopsy complications. Conclusions: mpMRI confirms its role as a reliable diagnostic tool prior to performing prostate biopsy in patients who underwent a previous negative biopsy, reporting a comparable detection rate of clinically significant prostate cancer.

Is There Still a Need for Repeated Systematic Biopsies in Patients with Previous Negative Biopsies in the Era of Magnetic Resonance Imaging-targeted Biopsies of the Prostate?

BACKGROUND

The role of targeted prostate biopsies (TBs) in patients with cancer suspicious lesions on multiparametric magnetic resonance imaging (mpMRI) following negative systematic biopsies (SBs) is undebated. However, whether they should be combined with repeated SBs remains unclear.

OBJECTIVE

To evaluate the value of repeated SBs in addition to TBs in patients with a prior negative SB and a persistent suspicion of prostate cancer (PCa).

DESIGN, SETTING, AND PARTICIPANTS

A prospective study as part of a multicenter randomized controlled trial conducted between 2014 and 2017, including 665 men with a prior negative SB and a persistent suspicion of PCa (suspicious digital rectal examination and/or prostate-specific antigen >4.0ng/ml).

INTERVENTION

All patients underwent 3T mpMRI according to Prostate Imaging Reporting and Data System (PI-RADS) v2. Patients with PI-RADS ≥3 were randomized 1:1:1 for three TB techniques: MRI-TRUS fusion TB (FUS-TB), cognitive registration fusion TB (COG-TB), or in-bore MRI TB. FUS-TB and COG-TB were combined with repeated SBs.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Clinically significant prostate cancer (csPCa) was defined as Gleason ≥3+4. Differences in detection rates of csPCa, clinically insignificant PCa (cisPCa), and overall PCa between TBs (FUS-TB and COG-TB) and repeated SBs were compared using McNemar's test.

RESULTS AND LIMITATIONS

In the 152 patients who underwent both TB and SB, PCa was detected by TB in 47% and by SB in 32% (p<0.001, 95% confidence interval [CI]: 6.0-22%). TB detected significantly more csPCa than SB (32% vs 16%; p<0.001, 95% CI: 11-25%). Clinically significant PCa was missed by TB in 1.3% (2/152). Combining SB and TB resulted in detection rate differences of 6.0% for PCa, 5.0% for cisPCa, and 1.0% for csPCa compared with TB alone.

CONCLUSIONS

In case of a persistent suspicion of PCa following a negative SB, TB detected significantly more csPCa cases than SB. The additional value of SB was limited, and only 1.3% of csPCa would have been missed when SB had been omitted.

PATIENT SUMMARY

We evaluated the role of systematic biopsies and magnetic resonance imaging (MRI)-targeted biopsies for the diagnosis of prostate cancer in patients with prior negative systematic biopsies. MRI-targeted biopsies perform better in detecting prostate cancer in these patients. The value of repeated systematic biopsies is limited.

Predictive factors of prostate cancer diagnosis with PSA 4.0-10.0 ng/ml in a multi-ethnic Asian population, Malaysia

OBJECTIVES

To identify the associated factors determining prostate cancer detection using transrectal ultrasound (TRUS)-guided prostate biopsy, within a multi-ethnic Malaysian population with prostate specific antigen (PSA) between 4.0 and 10.0 ng/ml.

METHODS

Study subjects included men with initial PSA between 4.0 and 10.0 ng/ml that have undergone 12-core TRUS-guided prostate biopsy between 2009 and 2016. The prostate cancer detection rate was calculated, while potential factors associated with detection were investigated via univariable and multivariable analysis.

RESULTS

A total of 617 men from a multi-ethnic background encompassing Chinese (63.5%), Malay (23.1%) and Indian (13.3%) were studied. The overall cancer detection rate was 14.3% (88/617), which included cancers detected at biopsy 1 (first biopsy), biopsy 2 (second biopsy with previous negative biopsy) and biopsy ≥ 3 (third or more biopsies with prior negative biopsies). Indian men displayed higher detection rate (23.2%) and increased risk of prostate cancer development (OR 1.85, 95% CI 1.03-3.32, p < 0.05), compared to their Malay (9.8%) and Chinese (14.0%) counterparts. Multivariable analysis revealed that ethnicity and PSA density (PSAD) are independent factors associated with overall prostate cancer detection rate. A unit increase of PSAD reflected an increase in PSA after controlling for prostate volume.

CONCLUSION

Prostate cancer detection in Malaysia is comparatively lower. Our study suggests that ethnicity and PSA density should be considered when recommending first or repeat TRUS-guided prostate biopsy for prostate cancer detection in a multi-ethnic Malaysian population.

The clinical effectiveness and cost-effectiveness of the PROGENSA® prostate cancer antigen 3 assay and the Prostate Health Index in the diagnosis of prostate cancer: a systematic review and economic evaluation

BACKGROUND

There is no single definitive test to identify prostate cancer in men. Biopsies are commonly used to obtain samples of prostate tissue for histopathological examination. However, this approach frequently misses cases of cancer, meaning that repeat biopsies may be necessary to obtain a diagnosis. The PROGENSA(®) prostate cancer antigen 3 (PCA3) assay (Hologic Gen-Probe, Marlborough, MA, USA) and the Prostate Health Index (phi; Beckman Coulter Inc., Brea, CA, USA) are two new tests (a urine test and a blood test, respectively) that are designed to be used to help clinicians decide whether or not to recommend a repeat biopsy.

OBJECTIVE

To evaluate the clinical effectiveness and cost-effectiveness of the PCA3 assay and the phi in the diagnosis of prostate cancer.

DATA SOURCES

Multiple publication databases and trial registers were searched in May 2014 (from 2000 to May 2014), including MEDLINE, EMBASE, The Cochrane Library, ISI Web of Science, Medion, Aggressive Research Intelligence Facility database, ClinicalTrials.gov, International Standard Randomised Controlled Trial Number Register and World Health Organization International Clinical Trials Registry Platform.

REVIEW METHODS

The assessment of clinical effectiveness involved three separate systematic reviews, namely reviews of the analytical validity, the clinical validity of these tests and the clinical utility of these tests. The assessment of cost-effectiveness comprised a systematic review of full economic evaluations and the development of a de novo economic model.

SETTING

The perspective of the evaluation was the NHS in England and Wales.

PARTICIPANTS

Men suspected of having prostate cancer for whom the results of an initial prostate biopsy were negative or equivocal.

INTERVENTIONS

The use of the PCA3 score or phi in combination with existing tests (including histopathology results, prostate-specific antigen level and digital rectal examination), multiparametric magnetic resonance imaging and clinical judgement.

RESULTS

In addition to documents published by the manufacturers, six studies were identified for inclusion in the analytical validity review. The review identified issues concerning the precision of the PCA3 assay measurements. It also highlighted issues relating to the storage requirements and stability of samples intended for analysis using the phi assay. Fifteen studies met the inclusion criteria for the clinical validity review. These studies reported results for 10 different clinical comparisons. There was insufficient evidence to enable the identification of appropriate test threshold values for use in a clinical setting. In addition, the implications of adding either the PCA3 assay or the phi to clinical assessment were not clear. Furthermore, the addition of the PCA3 assay or the phi to clinical assessment plus magnetic resonance imaging was not found to improve discrimination. No published papers met the inclusion criteria for either the clinical utility review or the cost-effectiveness review. The results from the cost-effectiveness analyses indicated that using either the PCA3 assay or the phi in the NHS was not cost-effective.

LIMITATIONS

The main limitations of the systematic review of clinical validity are that the review conclusions are over-reliant on findings from one study, the descriptions of clinical assessment vary widely within reviewed studies and many of the reported results for the clinical validity outcomes do not include either standard errors or confidence intervals.

CONCLUSIONS

The clinical benefit of using the PCA3 assay or the phi in combination with existing tests, scans and clinical judgement has not yet been confirmed. The results from the cost-effectiveness analyses indicate that the use of these tests in the NHS would not be cost-effective.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014009595.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

In-Bore MR-Guided Biopsy Systems and Utility of PI-RADS

A diagnostic dilemma exists in cases wherein a patient with clinical suspicion for prostate cancer has a negative transrectal ultrasound-guided biopsy session. Although transrectal ultrasound-guided biopsy is the standard of care, a paradigm shift is being observed. In biopsy-naive patients and patients with at least 1 negative biopsy session, multiparametric magnetic resonance imaging (MRI) is being utilized for tumor detection and subsequent targeting. Several commercial devices are now available for targeted prostate biopsy ranging from transrectal ultrasound-MR fusion biopsy to in bore MR-guided biopsy. In this review, we will give an update on the current status of in-bore MRI-guided biopsy systems and discuss value of prostate imaging-reporting and data system (PIRADS).

3T MR-guided in-bore transperineal prostate biopsy: A comparison of robotic and manual needle-guidance templates

PURPOSE

To demonstrate the utility of a robotic needle-guidance template device as compared to a manual template for in-bore 3T transperineal magnetic resonance imaging (MRI)-guided prostate biopsy.

MATERIALS AND METHODS

This two-arm mixed retrospective-prospective study included 99 cases of targeted transperineal prostate biopsies. The biopsy needles were aimed at suspicious foci noted on multiparametric 3T MRI using manual template (historical control) as compared with a robotic template. The following data were obtained: the accuracy of average and closest needle placement to the focus, histologic yield, percentage of cancer volume in positive core samples, complication rate, and time to complete the procedure.

RESULTS

In all, 56 cases were performed using the manual template and 43 cases were performed using the robotic template. The mean accuracy of the best needle placement attempt was higher in the robotic group (2.39 mm) than the manual group (3.71 mm, P < 0.027). The mean core procedure time was shorter in the robotic (90.82 min) than the manual group (100.63 min, P < 0.030). Percentage of cancer volume in positive core samples was higher in the robotic group (P < 0.001). Cancer yields and complication rates were not statistically different between the two subgroups (P = 0.557 and P = 0.172, respectively).

CONCLUSION

The robotic needle-guidance template helps accurate placement of biopsy needles in MRI-guided core biopsy of prostate cancer.

MRI-guided biopsy for prostate cancer detection: a systematic review of current clinical results

In-bore magnetic resonance-guided biopsy (MRGB) has been increasingly used in clinical practice to detect prostate cancer (PCa). This review summarizes the current clinical results of this biopsy method. A systematic literature search was performed in the PubMed and Embase databases. Of 2,035 identified records, 49 required full review. In all, ten unique studies reporting clinical results of MRGB could be included. Reported PCa detection rates ranged from 8 to 59 % (median 42 %). The majority of tumors detected by MRGB were clinically significant (81-93 %). Most frequent complications of MRGB are transient hematuria (1-24 %) and short-term perirectal bleeding (11-17 %). Major complications are rare. Based on the reviewed literature, MRGB can be regarded an accurate and safe diagnostic tool to detect clinically significant PCa. However, as general availability is limited, this procedure should be reserved for specific patients. Appropriate indications will have to be determined.

Detection rate of clinically insignificant prostate cancer increases with repeat prostate biopsies

To analyze if clinically insignificant prostate cancer (CIPC) is more frequently detected with repeat prostate biopsies, we retrospectively analyzed the records of 2146 men diagnosed with prostate cancer after one or more prostate biopsies. The patients were divided into five groups according to the number of prostate biopsies obtained, e.g. group 1 had one biopsy, group 2 had two biopsies and group 3 had three biopsies. Of the 2146 patients diagnosed with prostate cancer, 1956 (91.1%), 142 (6.6%), 38 (1.8%), 9 (0.4%) and 1 (0.1%) men were in groups 1, 2, 3, 4 and 5, respectively. Groups 4 and 5 were excluded because of the small sample sizes. The remaining three groups (groups 1, 2 and 3) were statistically analyzed. There were no differences in age or prostate-specific antigen level among the three groups. CIPC was detected in 201 (10.3%), 28 (19.7%) and 9 (23.7%) patients in groups 1, 2 and 3, respectively (P<0.001). A multivariate analysis showed that the number of biopsies was an independent predictor to detect CIPC (OR=2.688 for group 2; OR=4.723 for group 3). In conclusion, patients undergoing multiple prostate biopsies are more likely to be diagnosed with CIPC than those who only undergo one biopsy. However, the risk still exists that the patient could have clinically significant prostate cancer. Therefore, when counseling patients with regard to serial repeat biopsies, the possibility of prostate cancer overdiagnosis and overtreatment must be balanced with the continued risk of clinically significant disease.

3.0 T multiparametric prostate MRI using pelvic phased-array coil: utility for tumor detection prior to biopsy

OBJECTIVE

To evaluate the role of multiparametric magnetic resonance imaging (MRI) performed in men without a biopsy-proven diagnosis of prostate cancer using follow-up biopsy as the reference standard.

MATERIALS AND METHODS

Forty-two patients without biopsy-proven cancer and who underwent MRI were included. In all patients, MRI was performed at 3T using a pelvic phased-array coil and included T2-weighted imaging, diffusion-weighted imaging, and dynamic contrast-enhanced imaging. Thirteen had undergone no previous biopsy, and 29 had undergone at least 1 previous negative biopsy. All patients underwent prostate biopsy following MRI. Two fellowship-trained radiologists in consensus reviewed all cases and categorized each lobe as positive or negative for tumor. These interpretations were correlated with findings on post-MRI biopsy.

RESULTS

Follow-up biopsy was positive in 23 lobes in 15 patients (36% of study cohort). On a per-patient basis, MRI had a sensitivity of 100%, specificity of 74%, positive predictive value (PPV) of 68%, and negative predictive value (NPV) of 100%. On a per-lobe basis, MRI had a sensitivity of 65%, specificity of 84%, PPV of 60%, and NPV of 86%. There was a nearly significant association between Gleason score and tumor detection on MRI (P = 0.072).

CONCLUSIONS

In our sample, MRI had 100% sensitivity in predicting the presence of tumor on subsequent biopsy on a per-patient basis, suggesting a possible role for MRI in selecting patients with an elevated prostatic specific antigen (PSA) to undergo prostate biopsy. However, MRI had weaker specificity for prediction of a subsequent positive biopsy, as well as weaker sensitivity for tumor on a per-lobe basis, indicating that in patients with a positive MRI result, tissue sampling remains necessary for confirmation of the diagnosis as well as for treatment planning.

MRI of localized prostate cancer: coming of age in the PSA era

Prostate cancer is the most common cancer among American men. It varies widely in aggressiveness, ranging from completely indolent to highly aggressive. Currently, predicting the natural history of a particular tumor and deciding on the appropriate treatment, which might include active surveillance, surgery, radiation or hormonal therapies, are based on the condition and age of the patient as well as the presumed stage of the disease. Imaging plays an important role in staging localized prostate cancer. Magnetic resonance imaging (MRI) best depicts the zonal anatomy, with a superior soft tissue resolution providing better results for tumor localization, monitoring, and local staging. Previously, the major function of prostate MRI has been in staging, and this role remains important. In this article, we introduce the reader to the expanding roles that MRI plays in the management of localized prostate cancer.

MRI-guided prostate biopsy detects clinically significant cancer: analysis of a cohort of 100 patients after previous negative TRUS biopsy

PURPOSE

To investigate the positive biopsy rate of MRI-guided biopsy (MR-GB) in a routine clinical setting, identify factors predictive for positive biopsy findings and to report about the clinical significance of the diagnosed tumors.

METHODS

Patients with at least one negative trans-rectal-ultrasound-guided biopsy (TRUS-GB), persistently elevated or rising serum prostate specific antigen (PSA) and at least one lesion suspicious for PCa on diagnostic 1.5 Tesla endorectal coil MRI (eMR) were included. Biopsies were carried out using a 1.5 Tesla MRI and an 18 G biopsy gun. Clinical information and biopsy results were collected; logistic regression analysis was carried out. Definite pathology reports of patients with diagnosis of PCa and subsequent radical prostatectomy (RP) were analyzed for criteria of clinical significance.

RESULTS

One hundred patients were included, mean number of previous biopsies was 2 (range 1-9), mean PSA at time of biopsy was 11.7 ng/ml (1.0-65.0), and mean prostate volume was 46.7 ccm (range 13-183). In 52/100 (52.0%) patients, PCa was detected. Out of 52 patients, 27 patients with a positive biopsy underwent RP, 20 patients radiation therapy, and 5 patients active surveillance. In total, 80.8% of the patients revealed a clinically significant PCa. In univariate regression analysis, only serum PSA levels were predictive for a positive biopsy result. Number of preceding negative biopsies was not associated with the likelihood of a positive biopsy result.

CONCLUSIONS

MR-GB shows a high detection rate of clinically significant PCa in patients with previous negative TRUS-GB and persisting suspicion for PCa.

Repeat prostate biopsy and the incremental risk of clinically insignificant prostate cancer

OBJECTIVES

To determine the incremental risk of diagnosis of clinically insignificant prostate cancer with serial prostate biopsies.

METHODS

We reviewed our institutional radical prostatectomy (RP) database comprising 2411 consecutive patients undergoing RP. We then stratified patients by the prostate biopsy on which their cancer was diagnosed and correlated biopsy number with the risk of clinically insignificant disease and adverse pathology at radical prostatectomy.

RESULTS

A total of 1867 (77.4%), 281 (11.9%), and 175 (7.3%) patients underwent 1, 2, and 3 or more prostate biopsies, respectively, before RP. Increasing number of prostate biopsies was associated with increasing prostate volume (P <.01), prostate-specific antigen (P <.01), associated prostate intraepithelial neoplasia (P <.01), and increased likelihood of clinical Gleason 6 or less disease (P <.01). On pathologic analysis, increasing number of prostate biopsies was associated with increased risk of low-volume (P <.01), organ-confined (P <.01) disease. The risk of clinically insignificant disease was found to be 31.1%, 43.8%, and 46.8% in those undergoing 1, 2, and 3+ prostate biopsies, respectively. Conversely, the risk of adverse pathology was found to be 64.6%, 53.0%, and 52.0% in those undergoing 1, 2, and 3+ prostate biopsies, respectively.

CONCLUSIONS

Patients undergoing multiple prostate biopsies before RP are more likely to harbor clinically insignificant prostate cancer than those who only undergo 1 biopsy before resection. Nonetheless, the risk of adverse pathology in patients undergoing serial biopsies remains significant. The increased risk of prostate cancer overdiagnosis and overtreatment must be balanced with the continued risk of clinically significant disease when counseling patients regarding serial biopsies.

A four-kallikrein panel for the prediction of repeat prostate biopsy: data from the European Randomized Study of Prostate Cancer screening in Rotterdam, Netherlands

Background:

Most men with elevated levels of prostate-specific antigen (PSA) do not have prostate cancer, leading to a large number of unnecessary biopsies. A statistical model based on a panel of four kallikreins has been shown to predict the outcome of a first prostate biopsy. In this study, we apply the model to an independent data set of men with previous negative biopsy but persistently elevated PSA.

Methods:

The study cohort consisted of 925 men with a previous negative prostate biopsy and elevated PSA (⩾3 ng ml⁻¹), with 110 prostate cancers detected (12%). A previously published statistical model was applied, with recalibration to reflect the lower positive biopsy rates on rebiopsy.

Results:

The full-kallikrein panel had higher discriminative accuracy than PSA and DRE alone, with area under the curve (AUC) improving from 0.58 (95% confidence interval (CI): 0.52, 0.64) to 0.68 (95% CI: 0.62, 0.74), P<0.001, and high-grade cancer (Gleason ⩾7) at biopsy with AUC improving from 0.76 (95% CI: 0.64, 0.89) to 0.87 (95% CI: 0.81, 0.94), P=0.003). Application of the panel to 1000 men with persistently elevated PSA after initial negative biopsy, at a 15% risk threshold would reduce the number of biopsies by 712; would miss (or delay) the diagnosis of 53 cancers, of which only 3 would be Gleason 7 and the rest Gleason 6 or less.

Conclusions:

Our data constitute an external validation of a previously published model. The four-kallikrein panel predicts the result of repeat prostate biopsy in men with elevated PSA while dramatically decreasing unnecessary biopsies.

Value of endorectal MRI and MRS in patients with elevated prostate-specific antigen levels and previous negative biopsies to localize peripheral zone tumours

AIM

To evaluate prospectively the role of endorectal magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) in detecting peripheral zone tumour in patients with total prostate-specific antigen (PSA) values>or=4 ng/ml and one or more negative transrectal ultrasound (TRUS) biopsy rounds.

MATERIAL AND METHODS

Fifty-four consecutive men (mean age 65.4+/-5.2 years, mean total PSA 10.8+/-7.5 ng/ml), underwent a combined MRI-MRS examination with endorectal coil. MRI included transverse, coronal, and sagittal T2-weighted and transverse T1-weighted fast spin-echo sequences. MRS data were acquired using a double spin-echo point resolved spectroscopy (PRESS) sequence. A 10-site scheme was adopted to evaluate the prostate peripheral zone. A peripheral prostatic site was classified as suspicious if low intensity signal was present on T2-weighted images and/or if the choline+creatine/citrate ratio was >0.86. Following MRI-MRS all patients were submitted to a standard 10-core biopsy scheme to which from one to three supplementary samples were added from suspicious MRI and/or MRS sites. In per-patient analysis findings were considered true-positive if biopsy positive patients were classified as suspicious, irrespectively of lesion site indication.

RESULTS

Prostate cancer (PC) was detected in 17 of 54 patients (31.5%); median Gleason score was 6 (range 4-8). On a per-patient basis sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were respectively 100, 64.9, 56.7, 100, and 75.9% for MRI; 82.2, 70.3, 57.7, 92.9, and 75.9% for MRS; and 100, 51.4, 48.6, 100, and 66.7% for combined MRI-MRS. In all the 17 PC patients, combined MRI-MRS correctly indicated the sites harbouring cancer, whereas both MRI and MRS gave erroneous indications in two patients.

CONCLUSION

The results of the present study show that MRI alone might be able to select negative patients in whom further biopsies are unnecessary. The combination of MRI and MRS might be able to drive biopsies in suspicious sites and increase the cancer detection rate. Further studies are required to confirm these data.

Morphologic, Functional, and Metabolic Magnetic Resonance Imaging-Guided Prostate Biopsy in a Patient with Prior Negative Transrectal Ultrasound-Guided Biopsies and Persistently Elevated Prostate-Specific Antigen Levels

A 65-year-old patient was examined with [11C]-choline positron emission tomography-computed tomography and magnetic resonance imaging (MRI) for possible tumor detection after two negative sessions of transrectal ultrasound-guided prostate biopsy and persistently elevated prostate-specific antigen levels for 27 months. Choline positron emission tomography revealed a small and circumscribed pathologic tracer uptake in the right dorsal peripheral gland. Whereas T2-weighted MRI and high b-value diffusion-weighted imaging were able to reproduce this suspicious area, proton MR spectroscopy showed no significant increase of the amplitude of choline-containing compounds. Magnetic resonance imaging-guided prostate biopsy was successfully performed. All specimens taken from the lesion showed a Gleason 5 tubular adenocarcinoma with low proliferative activity.

Prostate needle biopsies containing prostatic intraepithelial neoplasia or atypical foci suspicious for carcinoma: implications for patient care

PURPOSE

We identified information critical for patient treatment on prostate needle biopsies diagnosed with prostatic intraepithelial neoplasia or atypical foci suspicious for carcinoma.

MATERIALS AND METHODS

A search was performed using the MEDLINE database and referenced lists of relevant studies to obtain articles addressing the significance of finding PIN or atypical foci suspicious for carcinoma on needle biopsy.

RESULTS

There were certain results concerning PIN. 1) Low grade PIN should not be documented in pathology reports due to poor interobserver reproducibility and a relatively low risk of cancer following re-biopsy. 2) The expected incidence of HGPIN on needle biopsy is between 5% and 8%. 3) Although the diagnosis of HGPIN is subjective, interobserver reproducibility for its diagnosis is fairly high among urological pathologists, and yet only moderate among pathologists without special expertise in prostate pathology. 4) The median risk recorded in the literature for cancer following the diagnosis of HGPIN on needle biopsy is 24.1%, which is not much higher than the risk reported in the literature for repeat biopsy following a benign diagnosis. 5) The majority of publications that compared the risk of cancer in the same study following a needle biopsy diagnosis of HGPIN to the risk of cancer following a benign diagnosis on needle biopsy show no differences between the 2 groups. 6) Clinical and pathological parameters do not help stratify which men with HGPIN are at increased risk for a cancer diagnosis. 7) A major factor contributing to the decreased incidence of cancer following a diagnosis of HGPIN on needle biopsy in the contemporary era is related to increased needle biopsy core sampling, which detects many associated cancers on initial biopsy, such that re-biopsy, even with good sampling, does not detect many additional cancers. 8) It is recommended that men do not need routine repeat needle biopsy within the first year following the diagnosis of HGPIN, while further studies are needed to confirm whether routine repeat biopsies should be performed several years following a HGPIN diagnosis on needle biopsy. There were certain results concerning atypical glands suspicious for carcinoma. 1) An average of 5% of needle biopsy pathology reports are diagnosed as atypical glands suspicious for carcinoma. 2) Cases diagnosed as atypical have the highest likelihood of being changed upon expert review and urologists should consider sending such cases for consultation in an attempt to resolve the diagnosis as definitively benign or malignant before subjecting the patient to repeat biopsy. 3) Ancillary techniques using basal cell markers and AMACR (alpha-methyl-acyl-coenzyme A racemase) can decrease the number of atypical diagnoses, and yet one must use these techniques with caution since there are numerous false-positive and false-negative results. 4) The average risk of cancer following an atypical diagnosis is approximately 40%. 5) Clinical and pathological parameters do not help predict which men with an atypical diagnosis have cancer on repeat biopsy. 6) Repeat biopsy should include increased sampling of the initial atypical site, and adjacent ipsilateral and contralateral sites with routine sampling of all sextant sites. Therefore, it is critical for urologists to submit needle biopsy specimens in a manner in which the sextant location of each core can be determined. 7) All men with an atypical diagnosis need re-biopsy within 3 to 6 months.

CONCLUSIONS

It is critical for urologists to distinguish between a diagnosis of HGPIN and that of atypical foci suspicious for cancer on needle biopsy. These 2 entities indicate different risks of carcinoma on re-biopsy and different recommendations for followup.

MRI-guided biopsy of the prostate increases diagnostic performance in men with elevated or increasing PSA levels after previous negative TRUS biopsies

OBJECTIVES

Repeatedly negative prostate biopsies in individuals with elevated prostate specific antigen (PSA) levels can be frustrating for both the patient and the urologist. This study was performed to investigate if magnetic resonance imaging (MRI)-guided transrectal biopsy increases diagnostic performance in individuals with elevated or increasing PSA levels after previous negative conventional transrectal ultrasound (TRUS)-guided biopsies.

METHODS

27 consecutive men with a PSA >4 ng/ml and/or suspicious finding on digital rectal examination, suspicious MRI findings, and at least one prior negative prostate biopsy were included. Median age was 66 years (mean, 64.5+/-6.8); median PSA was 10.2 ng/ml (mean, 11.3+/-5.5). MRI-guided biopsy was performed with a closed unit at 1.5 Tesla, an MRI-compatible biopsy device, a needle guide, and a titanium double-shoot biopsy gun.

RESULTS

Median prostate volume was 37.4 cm3 (mean, 48.4+/-31.5); median volume of tumor suspicious areas on T2w MR images was 0.83 cm3 (mean, 0.99+/-0.78). The mean number of obtained cores per patient was 5.22+/-1.45 (median, 5; range, 2-8). Prostate cancer was detected in 55.5% (15 of 27) of the men. MRI-guided biopsy could be performed without complications in all cases.

CONCLUSION

According to our knowledge, this is the largest cohort of consecutive men to be examined by MRI-guided transrectal biopsy of the prostate in this setting. The method is safe, can be useful to select suspicious areas in the prostate, and has the potential to improve cancer detection rate in men with previous negative TRUS-biopsies.