Pathologic prostate cancer characteristics in patients eligible for active surveillance: a head-to-head comparison of contemporary protocols.
ABSTRACT Although the rationale for active surveillance (AS) in patients with low-risk prostate cancer is well established, eligibility criteria vary significantly across different programs.
To compare the ability of contemporary AS criteria to identify patients with certain pathologic tumor features based on the results of an extended transrectal prostate biopsy.
The study cohort included 391 radical prostatectomy patients who had prostate cancer with Gleason scores ≤ 6 on transrectal biopsy with ≥ 10 cores.
Radical prostatectomy without neoadjuvant treatment. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We identified patients who fulfilled the inclusion criteria of five AS protocols including those of Epstein, Memorial Sloan-Kettering Cancer Center, Prostate Cancer Research International: Active Surveillance (PRIAS), University of California, San Francisco, and University of Miami (UM). We evaluated the ability of these criteria to predict three pathologic end points: insignificant disease defined using a classical and updated formulation, and organ-confined Gleason ≤ 6 prostate cancer. Measures of diagnostic accuracy and areas under the receiver operating curve were calculated for each protocol and compared.
A total of 75% of the patients met the inclusion criteria of at least one protocol; 23% were eligible for AS by all studied criteria. The PRIAS and UM criteria had the best balance between sensitivity and specificity for both definitions of insignificant prostate cancer and a higher discriminative ability for the end points than any criteria including patients with two or more positive cores. The Epstein criteria demonstrated high specificity but low sensitivity for all pathologic end points, and therefore the discriminative ability was not superior to those of other protocols.
Significant variations exist in the ability of contemporary AS criteria to predict pathologically insignificant prostate cancer at radical prostatectomy. These differences should be taken into account when making treatment choices in patients with low-risk prostate cancer.
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ABSTRACT: BACKGROUND: The diagnosis of prostate cancer has long been plagued by the absence of an imaging tool that reliably detects and localises significant tumours. Recent evidence suggests that multi-parametric MRI could improve the accuracy of diagnostic assessment in prostate cancer. This review serves as a background to a recent USANZ position statement. It aims to provide an overview of MRI techniques and to critically review the published literature on the clinical application of MRI in prostate cancer. TECHNICAL ASPECTS: The combination of anatomical (T2-weighted) MRI with at least two of the three functional MRI parameters - which include diffusion-weighted imaging, dynamic contrast-enhanced imaging and spectroscopy - will detect greater than 90% of significant (moderate to high risk) tumours; however MRI is less reliable at detecting tumours that are small (<0.5 cc), low grade (Gleason score 6) or in the transitional zone. The higher anatomical resolution provided by 3-Tesla magnets and endorectal coils may improve the accuracy, particularly in primary tumour staging. SCREENING: The use of mpMRI to determine which men with an elevated PSA should undergo biopsy is currently the subject of two large clinical trials in Australia. MRI should be used with caution in this setting and then only in centres with established uro-radiological expertise and quality control mechanisms in place. There is sufficient evidence to justify using MRI to determine the need for repeat biopsy and to guide areas in which to focus repeat biopsy. IMAGE-DIRECTED BIOPSY: MRI-directed biopsy is an exciting concept supported by promising early results, but none of the three proposed techniques have so far been proven superior to standard biopsy protocols. Further evidence of superior accuracy and core-efficiency over standard biopsy is required, before their costs and complexities in use can be justified. TREATMENT SELECTION AND PLANNING: When used for primary-tumour staging (T-staging), MRI has limited sensitivity for T3 disease, but its specificity of greater than 95% may be useful in men with intermediate-high risk disease to identify those with advanced T3 disease not suitable for nerve sparing or for surgery at all. MRI appears to be of value in planning dosimetry in men undergoing radiotherapy, and in guiding selection for and monitoring on active surveillance.BJU International 01/2013; 112 Suppl 2:6-20. · 3.05 Impact Factor
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ABSTRACT: OBJECTIVE: To test the hypothesis that spatial distribution of positive cores at biopsy is a predictor of unfavourable prostate cancer characteristics at radical prostatectomy (RP) in active surveillance (AS) candidates. PATIENTS AND METHODS: We examined the data of 524 patients treated with RP, between 2000 and 2012. All fulfilled at least one of four commonly used AS criteria. Regression models tested the relationship between positive cores spatial distribution, defined as the number of positive zones at biopsy (PBxZ) and tumour laterality at biopsy and two endpoints: (i) unfavourable prostate cancer at RP (Gleason score ≥4 + 3, and/or pT3 disease), and (ii) clinically significant prostate cancer (tumour volume ≥2.5 mL). RESULTS: Unfavourable prostate cancer and clinically significant prostate cancer rates were 8 and 25%, respectively. Patients with more than one PBxZ had a 3.2-fold higher risk of harbouring unfavourable prostate cancer, and a 2.3-fold higher risk of harbouring clinically significant prostate cancer compared with their counterparts with one PBxZ (both P = 0.01). Patients with bilateral tumour at biopsy had a 3.3-fold higher risk of harbouring unfavourable prostate cancer and a 1.7-fold higher risk of harbouring clinically significant prostate cancer compared with their counterparts with unilateral tumour at biopsy (both P ≤ 0.04). Some of these results did not reach a statistically significant level, when the analyses were restricted to patients that fulfilled the most stringent AS criteria. CONCLUSIONS: Positive cores spatial distribution at biopsy should be considered, when advising patients about AS. The addition of this predictor to AS inclusion criteria can help identifying patients at a higher risk of progression, and reduce the rate of inappropriate surveillance of aggressive tumours. However, the most stringent AS criteria (namely John-Hopkins criteria and Prostate Cancer Research International: Active Surveillance criteria) might not benefit from the addition of this predictor. This point warrants further investigation in future studies.BJU International 06/2013; · 3.05 Impact Factor
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ABSTRACT: PURPOSE: To determine the utility of multiparametric-MRI (MP-MRI) in detecting prostate cancer (PCa), with specific focus on detecting higher-grade PCa. MATERIALS AND METHODS: Prospectively, 583 patients who underwent MP-MRI and subsequent prostate biopsy at a single institution were evaluated. On MP-MRI, lesions were identified and scored as low, moderate, or high suspicion for PCa based upon a validated scoring system. MR/US fusion-guided biopsies of MRI lesions in addition to systematic 12-core biopsies were performed. Correlations between the highest assigned MP-MRI suspicion score and presence of cancer and biopsy Gleason Score (bGS) on the first fusion biopsy session were assessed using univariate and multivariable logistic regression models. Sensitivity, specificity, NPV, and PPV were calculated and ROC curves were developed to assess the discriminative ability of MP-MRI as a diagnostic tool for various bGS cohorts. RESULTS: Significant correlations were found between age, PSA, prostate volume, and MP-MRI suspicion score and the presence of PCa (p<0.0001). On multivariable analyses controlling for age, PSA, and prostate volume, increasing MP-MRI suspicion was an independent prognosticator of PCa detection (OR=2.2, p<0.0001). Also, incremental increases in MP-MRI suspicion score demonstrated stronger associations with cancer detection in patients with Gleason ≥7 (OR=3.3, p<0.001) and Gleason ≥8 (OR=4.2, p<0.0001) PCa. Assessing MP-MRI as a diagnostic tool for all PCa, bGS≥7, and bGS≥8 separately via ROC analyses demonstrated increasing accuracy of MP-MRI for higher-grade disease (AUC=0.64, 0.69, and 0.72, respectively). CONCLUSIONS: MP-MRI is a clinically useful modality to detect and characterize PCa, particularly in men with higher-grade disease.The Journal of urology 05/2013; · 3.75 Impact Factor