Testing the most stringent criteria for selection of candidates for active surveillance in patients with low-risk prostate cancer

[68Ga]Ga‑PSMA‑617 PET-based radiomics model to identify candidates for active surveillance amongst patients with GGG 1-2 prostate cancer at biopsy

PURPOSE

To develop a radiomics-based model using [68Ga]Ga-PSMA PET/CT to predict postoperative adverse pathology (AP) in patients with biopsy Gleason Grade Group (GGG) 1-2 prostate cancer (PCa), assisting in the selection of patients for active surveillance (AS).

METHODS

A total of 75 men with biopsy GGG 1-2 PCa who underwent radical prostatectomy (RP) were enrolled. The patients were randomly divided into a training group (70%) and a testing group (30%). Radiomics features of entire prostate were extracted from the [68Ga]Ga-PSMA PET scans and selected using the minimum redundancy maximum relevance algorithm and the least absolute shrinkage and selection operator regression model. Logistic regression analyses were conducted to construct the prediction models. Receiver operating characteristic (ROC) curve, decision curve analysis (DCA), and calibration curve were employed to evaluate the diagnostic value, clinical utility, and predictive accuracy of the models, respectively.

RESULTS

Among the 75 patients, 30 had AP confirmed by RP. The clinical model showed an area under the curve (AUC) of 0.821 (0.695-0.947) in the training set and 0.795 (0.603-0.987) in the testing set. The radiomics model achieved AUC values of 0.830 (0.720-0.941) in the training set and 0.829 (0.624-1.000) in the testing set. The combined model, which incorporated the Radiomics score (Radscore) and free prostate-specific antigen (FPSA)/total prostate-specific antigen (TPSA), demonstrated higher diagnostic efficacy than both the clinical and radiomics models, with AUC values of 0.875 (0.780-0.970) in the training set and 0.872 (0.678-1.000) in the testing set. DCA showed that the net benefits of the combined model and radiomics model exceeded those of the clinical model.

CONCLUSION

The combined model shows potential in stratifying men with biopsy GGG 1-2 PCa based on the presence of AP at final pathology and outperforms models based solely on clinical or radiomics features. It may be expected to aid urologists in better selecting suitable patients for AS.

Prediction of clinically significant prostate cancer by [68 Ga]Ga-PSMA-11 PET/CT: a potential tool for selecting patients for active surveillance

PURPOSE

In our study, our aim was to investigate the role of [68 Ga]Ga-PSMA-11 PET /CT imaging in the diagnosis of clinically significant prostate cancer (csPCa) (ISUP GG 2 and higher) in patients initially diagnosed with ISUP GG 1 and 2 after prostate biopsy.

MATERIALS AND METHODS

We retrospectively reviewed 147 patient records in whom [68 Ga]Ga-PSMA-11 PET/CT imaging was performed preoperatively. All patients were initially diagnosed with ISUP GG 1 and 2 PCa by biopsy. Final pathology reports were obtained after radical prostatectomy. The [68 Ga]Ga-PSMA-11 PET/CT images were evaluated to determine the PRIMARY score. Patients' mpMRI-PIRADS scores were also recorded when available and analyzed in correlation with the pathology results.

RESULTS

For the 114 patients scored using PRIMARY, 19 out of 37 patients with scores of 1 and 2 (51%) were diagnosed with csPCa. Of the 77 patients with PRIMARY scores between 3 and 5, 64 (83%) had csPCa. Notably, every patient with a PRIMARY score of 5 had csPCa. PRIMARY scoring had a sensitivity of 77% and specificity of 58%, with a positive predictive value of 83%. A moderate correlation was observed between PRIMARY scores and ISUP GG (Rho = 0.54, p < 0.001). In contrast, the PIRADS score displayed a sensitivity and specificity of 86% and 25% respectively, with a positive predictive value of 68%. No substantial correlation was found between PIRADS and ISUP GG. Statistical analysis revealed a significant correlation between PRIMARY and ISUP GG (p < 0.001), but not between PIRADS and ISUP GG (p = 0.281). Comparatively, PRIMARY scoring was significantly more reliable than PIRADS scoring in identifying csPCa.

CONCLUSION

[68 Ga]Ga-PSMA-11 PET/CT imaging is promising for distinguishing high-risk prostate cancer patients from those apt for active surveillance, potentially aiding in the identification of csPCa.

Multiparametric magnetic resonance imaging and clinical variables: Which is the best combination to predict reclassification in active surveillance patients?

Introduction & objectives

We tested the role of multiparametric magnetic resonance imaging (mpMRI) in disease reclassification and whether the combination of mpMRI and clinicopathological variables could represent the most accurate approach to predict the risk of reclassification during active surveillance.

Materials & methods

Three-hundred eighty-nine patients (pts) underwent mpMRI and subsequent confirmatory or follow-up biopsy according to the Prostate Cancer Research International Active Surveillance (PRIAS) protocol. Pts with negative (−) mpMRI underwent systematic random biopsy. Pts with positive (+) mpMRI [Prostate Imaging Reporting and Data System, version 2 (PI-RADS-V2) score ≥3] underwent targeted + systematic random biopsies. Multivariate analyses were used to create three models predicting the probability of reclassification [International Society of Urological Pathology ≥ Grade Group 2 (GG2)]: a basic model including only clinical variables (age, prostate-specific antigen density, and number of positive cores at baseline), an Magnetic resonance imaging (MRI) model including only the PI-RADS score, and a full model including both the previous ones. The predictive accuracy (PA) of each model was quantified using the area under the curve.

Results

mpMRI negative (−) was recorded in 127 (32.6%) pts; mpMRI positive (+) was recorded in 262 pts: 72 (18.5%) had PI-RADS 3, 150 (38.6%) PI-RADS 4, and 40 (10.3%) PI-RADS 5 lesions. At a median follow-up of 12 months, 125 pts (32%) were reclassified to GG2 prostate cancer. The rate of reclassification to GG2 prostate cancer was 17%, 35%, 38%, and 52% for mpMRI (−), PI-RADS 3, 4, and 5, respectively (P < 0.001). The PA was 69% and 64% in the basic and MRI models, respectively. The full model had the best PA of 74%: older age (P = 0.023; Odds ratio (OR) = 1.040), prostate-specific antigen density (P = 0.037; OR = 1.324), number of positive cores at baseline (P = 0.001; OR = 1.441), and PI-RADS 3, 4, and 5 (overall P = 0.001; OR = 2.458, 3.007, and 3.898, respectively) were independent predictors of reclassification.

Conclusions

Disease reclassification increased according to the PI-RADS score increase, at confirmatory or follow-up biopsy. However, a no-negligible rate of reclassification was found also in cases of mpMRI (−). The combination of mpMRI and clinicopathological variables still represents the most accurate approach to pts on active surveillance.

The Use of Multiparametric Magnetic Resonance Imaging for Follow-up of Patients Included in Active Surveillance Protocol. Can PSA Density Discriminate Patients at Different Risk of Reclassification?

INTRODUCTION

The objective of this study was to test Prostate Imaging Reporting and Data System (PI-RADS) classification on multiparametric magnetic resonance imaging (mpMRI) and MRI-derived prostate-specific antigen density (PSAD) in predicting the risk of reclassification in men in active surveillance (AS), who underwent confirmatory or per-protocol follow-up biopsy.

MATERIALS AND METHODS

Three hundred eighty-nine patients in AS underwent mpMRI before confirmatory or follow-up biopsy. Patients with negative (-) mpMRI underwent systematic random biopsy. Patients with positive (+) mpMRI underwent targeted fusion prostate biopsies + systematic random biopsies. Different PSAD cutoff values were tested (< 0.10, 0.10-0.20, ≥ 0.20). Multivariable analyses assessed the risk of reclassification, defined as clinically significant prostate cancer of grade group 2 or more, during follow-up according to PSAD, after adjusting for covariates.

RESULTS

One hundred twenty-seven (32.6%) patients had mpMRI(-); 72 (18.5%) had PI-RADS 3, 150 (38.6%) PI-RADS 4, and 40 (10.3%) PI-RADS 5 lesions. The rate of reclassification to grade group 2 PCa was 16%, 22%, 31%, and 39% for mpMRI(-) and PI-RADS 3, 4, and 5, respectively, in case of PSAD < 0.10 ng/mL²; 16%, 25%, 36%, and 44%, in case of PSAD 0.10 to 0.19 ng/mL²; and 25%, 42%, 55%, and 67% in case of PSAD ≥ 0.20 ng/mL². PSAD ≥ 0.20 ng/mL² (odds ratio [OR], 2.45; P = .007), PI-RADS 3 (OR, 2.47; P = .013), PI-RADS 4 (OR, 2.94; P < .001), and PI-RADS 5 (OR, 3.41; P = .004) were associated with a higher risk of reclassification.

CONCLUSION

PSAD ≥ 0.20 ng/mL² may improve predictive accuracy of mpMRI results for reclassification of patients in AS, whereas PSAD < 0.10 ng/mL² may help selection of patients at lower risk of harboring clinically significant prostate cancer. However, the risk of reclassification is not negligible at any PSAD cutoff value, also in the case of mpMRI(-).

The american urological association's prostate cancer screening guideline: Which cancers will be missed in average-risk men aged 40 to 54 years?

To determine the impact of the American Urological Association's (AUA) guideline for early detection of prostate cancer that recommends against routine screening in men aged 40 to 54 years at average risk (eg, white men without a family history of prostate cancer), we undertook a study of 973 men who previously underwent a prostate biopsy at Urology Centers of Alabama (UCA) over the 5-year period from 2010 to 2014. We retrospectively reviewed the results of the prostate biopsies performed by urologists at UCA-and, where applicable, the final surgical pathology results and compared the results by race and family history. In white men with a family history of prostate cancer, 47% had cancer and 30% had Gleason score (GS) ≥ 7 disease. In white men without a family history of prostate cancer, 32% had cancer and 23% had GS ≥ 7 disease. By comparison, in African American men with a family history of prostate cancer, 56% had cancer and 42% had GS ≥ 7 disease. In African American men without a family history, 42% had cancer and 29% had GS ≥ 7 disease. In our study, 144 of 456 (32%) of the group of average-risk men had cancer and 105 of 456 (23%) had GS ≥ 7 cancer. Had the AUA guidelines been followed, these cancers would have been missed or the diagnoses delayed.

Immediate versus delayed prostatectomy: Nationwide population-based study (.)

OBJECTIVE

The aim of this study was to compare the outcome of immediate versus delayed radical prostatectomy (RP) in men with low-grade prostate cancer.

MATERIALS AND METHODS

The study included a nationwide population-based cohort in the National Prostate Cancer Register of Sweden, of 7608 men with clinically localized, biopsy Gleason score 6 prostate cancer who underwent immediate or delayed RP in 1997-2007. Multivariable models compared RP pathology, use of salvage radiotherapy and prostate cancer mortality based on timing of RP (< 1, 1-2 or >2 years after diagnosis). Median follow-up was 8.1 years.

RESULTS

Men undergoing RP more than 2 years after diagnosis had a higher risk of Gleason upgrading [odds ratio 2.93, 95% confidence interval (CI) 2.34-3.68] and an increased risk of salvage radiotherapy [hazard ratio (HR) 1.90, 95% CI 1.41-2.55], but no significant increase in prostate cancer-specific mortality (HR 1.85, 95% CI 0.57-5.99). In competing risk analysis, 7 year prostate cancer-specific cumulative mortality was similar, at less than 1%, for immediate RP and active surveillance regardless of later intervention. Limitations of this study include the lack of data on follow-up biopsies and the limited follow-up time.

CONCLUSION

Men undergoing RP more than 2 years after diagnosis had more adverse pathological features and second line therapy, highlighting the trade-off in deferring immediate curative therapy. However, men with delayed RP constitute a minority with higher risk cancer among the much larger group of low-risk men initially surveilled, and the overall risk of prostate cancer mortality at 7 years was similarly low with immediate RP or active surveillance.

Stricter Active Surveillance Criteria for Prostate Cancer do Not Result in Significantly Better Outcomes: A Comparison of Contemporary Protocols

PURPOSE

We reviewed various existing active surveillance criteria and determined the competing trade-offs of the stricter vs more inclusive active surveillance criteria.

MATERIALS AND METHODS

Men enrolled in an active surveillance program at Princess Margaret Cancer Centre between 1998 and 2014 were identified through a prospectively maintained database. All patients were assessed for entry eligibility into the Prostate Cancer Research International: Active Surveillance, Johns Hopkins, University of Miami, University of California San Francisco, Memorial Sloan Kettering Cancer Center, University of Toronto-Sunnybrook and Royal Marsden protocols. The 2-sided t-test, ANOVA, Wilcoxon rank sum or chi-square tests were used for comparison as appropriate.

RESULTS

Of the 1,365 men identified 1,085 met the Princess Margaret Cancer Centre inclusion criteria. When the Johns Hopkins, Prostate Cancer Research International: Active Surveillance and University of Miami criteria were applied 15.2%, 11.5% and 11.3% of these patients were excluded from active surveillance, respectively. No significant differences were noted between men who met the Princess Margaret Cancer Centre criteria and those who were excluded based on more stringent criteria when grade or volume reclassification was compared. No significant differences in prostate specific antigen velocity or the number of patients who proceeded to seek treatment were noted (p >0.1). Rates of biochemical recurrence among patients who chose to undergo radical prostatectomy after initial active surveillance were not different between men who met the more inclusive vs more exclusive active surveillance protocols.

CONCLUSIONS

More selective criteria do not significantly improve short-term outcomes when considering the relative risk of grade reclassification or biochemical failure after treatment. In an era of increased awareness regarding the over diagnosis and overtreatment of prostate cancer, we believe that stricter entry criteria should be reconsidered.

Can Prostate-Specific Antigen Kinetics before Prostate Biopsy Predict the Malignant Potential of Prostate Cancer?

PURPOSE

To predict the malignant potential of prostate cancer (PCa) according to prostate-specific antigen velocity (PSAV), PSA density (PSAD), free/total PSA ratio (%fPSA), and digital rectal examination (DRE).

MATERIALS AND METHODS

From January 2009 to December 2012, 548 adult male patients were diagnosed with PCa by prostate biopsy at four hospitals in Korea. We retrospectively analyzed 155 adult male patients with an initial PSA level≤10 ng/mL and whose PSA levels had been checked more than two times at least 6 months before they had been diagnosed with PCa, with test intervals of more than 3 months. Patients with a urinary tract infection, and patients who had previously undergone cystoscopy or surgery of the prostate were excluded. We separated patients into two groups according to Gleason sum [Gleason sum≤7 (n=134) or Gleason sum≥8 (n=21)] and the presence of extracapsular invasion [organ confined (n=129) or extracapsular invasion (n=26)]. Differences between the groups were compared.

RESULTS

The group with a Gleason sum≥8 or extracapsular invasion of PCa showed high PSAV and significantly lower %fPSA. There were no significant differences in PSAD and the presence of an abnormality on DRE between two groups.

CONCLUSION

In PCa patients treated with other therapies besides prostatectomy, a high PSA velocity and a low %fPSA may predict high grade PCa with a Gleason sum≥8 or the presence of extracapsular invasion.

A Novel Quantitative Multiplex Tissue Immunoblotting for Biomarkers Predicts a Prostate Cancer Aggressive Phenotype

BACKGROUND

Early prediction of disease progression in men with very low-risk (VLR) prostate cancer who selected active surveillance (AS) rather than immediate treatment could reduce morbidity associated with overtreatment.

METHODS

We evaluated the association of six biomarkers [Periostin, (-5, -7) proPSA, CACNA1D, HER2/neu, EZH2, and Ki-67] with different Gleason scores and biochemical recurrence (BCR) on prostate cancer TMAs of 80 radical prostatectomy (RP) cases. Multiplex tissue immunoblotting (MTI) was used to assess these biomarkers in cancer and adjacent benign areas of 5 μm sections. Multivariate logistic regression (MLR) was applied to model our results.

RESULTS

In the RP cases, CACNA1D, HER2/neu, and Periostin expression were significantly correlated with aggressive phenotype in cancer areas. An MLR model in the cancer area yielded a ROC-AUC = 0.98, whereas in cancer-adjacent benign areas, yielded a ROC-AUC = 0.94. CACNA1D and HER2/neu expression combined with Gleason score in a MLR model yielded a ROC-AUC = 0.79 for BCR prediction. In the small biopsies from an AS cohort of 61 VLR cases, an MLR model for prediction of progressors at diagnosis retained (-5, -7) proPSA and CACNA1D, yielding a ROC-AUC of 0.78, which was improved to 0.82 after adding tPSA into the model.

CONCLUSIONS

The molecular profile of biomarkers is capable of accurately predicting aggressive prostate cancer on retrospective RP cases and identifying potential aggressive prostate cancer requiring immediate treatment on the AS diagnostic biopsy but limited in BCR prediction.

IMPACT

Comprehensive profiling of biomarkers using MTI predicts prostate cancer aggressive phenotype in RP and AS biopsies.

Active Surveillance is an Appropriate Management Strategy for a Proportion of Men Diagnosed with Prostate Cancer by Prostate Specific Antigen Testing

PURPOSE

The purpose of this study was to determine the fraction of men who would qualify for active surveillance in a population based cohort diagnosed with prostate cancer. In those who qualified and subsequently underwent primary treatment with radical prostatectomy, we assessed the rate of upgrading and up staging.

MATERIALS AND METHODS

SABOR is a Clinical and Epidemiologic Center of the EDRN (Early Detection Research Network), NCI (National Cancer Institute), with 3,828 men enrolled at the time of review. Of these men 320 were diagnosed with prostate cancer, of whom 281 had sufficient data for review. These 281 cases were reviewed to determine suitability for active surveillance using 2 sets of criteria. Criteria 1 were prostate specific antigen density less than 15%, 2 or fewer cores involved with cancer, Gleason score 6 or less and cancer involving 50% or less of biopsy volume. Criteria 2 were 4 or fewer cores with Gleason 3 + 3 cancer and only 1 core of Gleason 3 + 4 cancer with up to 15% of core involved with Gleason 3 + 4 disease. For those undergoing radical prostatectomy, we examined rates of up staging and upgrading.

RESULTS

Of the 281 patients, 187 (67%) qualified for active surveillance under criteria 1 and/or 2. Treatment data were available on 178 patients, and 74 underwent radical prostatectomy. Using the initial biopsy, 14 men (33.1%) who met criteria 1 and 9 (25%) who met criteria 2 were upgraded and/or up staged on final pathological review. By comparison, 38% of those who did not qualify for active surveillance were upgraded and/or up staged.

CONCLUSIONS

In a population based cohort, two-thirds of men diagnosed with prostate cancer qualify for active surveillance. Less restricted criteria for surveillance may be appropriate based on similar rates of upgrading/up staging at radical prostatectomy.

Initial management of prostate-specific antigen-detected, low-risk prostate cancer and the risk of death from prostate cancer

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The recently published Prostate Cancer Intervention versus Observation Trial (PIVOT) did not identify differences in prostate cancer-specific mortality or all-cause mortality among patients with low-risk disease managed conservatively vs those managed definitively; however, recently published data suggest that older men may harbour more aggressive disease than is identified at biopsy owing to sampling error and undergrading. Whether older men with apparent low-risk disease are placed at risk of prostate cancer-specific mortality when managed conservatively remains unknown. The study used population-level data to show that non-curative approaches for older men with low-risk prostate cancer do result in an increased risk of prostate cancer-specific mortality. Differences between our study and the PIVOT trial include the fact that we included a larger sample size, analysed the data using an 'as-treated' approach, and included a healthier cohort of men as evinced by lower 4-year all-cause mortality estimates in our study than in the PIVOT. Our results suggest that older men with apparent low-risk prostate cancer are at risk of undergrading, which probably explains the differences in prostate cancer-specific mortality observed between men managed conservatively vs those managed definitively. Our study suggests that alternative approaches to excluding occult, high grade prostate cancer are needed in such men.

OBJECTIVE

To evaluate whether older age in men with low-risk prostate cancer increases the risk of prostate cancer-specific mortality (PCSM) when non-curative approaches are selected as initial management.

PATIENTS AND METHODS

The study cohort consisted of 27 969 men, with a median age of 67 years, with prostate-specific antigen (PSA)-detected, low-risk prostate cancer (clinical category T1c, Gleason score ≤6, and PSA ≤10) identified by the Surveillance, Epidemiology and End Results programme between 2004 and 2007. Fine and Gray's competing risk regression analysis was used to evaluate whether management with non-curative vs curative therapy was associated with an increased risk of PCSM after adjusting for PSA level, age at diagnosis and year of diagnosis.

RESULTS

After a median follow-up of 2.75 years, 1121 men died, 60 (5.4%) from prostate cancer. Both older age (adjusted hazard ratio [AHR] 1.05; 95% confidence interval (CI) 1.02-1.08; P < 0.001) and non-curative treatment (AHR 3.34; 95% CI 1.97-5.67; P < 0.001) were significantly associated with an increased risk of PCSM. Men > the median age experienced increased estimates of PCSM when treated with non-curative as opposed to curative intent (P < 0.001); this finding was not seen in men ≤ the median age (P = 0.17).

CONCLUSION

Pending prospective validation, our study suggests that non-curative approaches for older men with 'low-risk' prostate cancer result in an increased risk of PCSM, suggesting the need for alternative approaches to exclude occult, high grade prostate cancer in these men.

Prostate cancer: can multiparametric MR imaging help identify patients who are candidates for active surveillance?

PURPOSE

To determine whether multiparametric magnetic resonance (MR) imaging can help identify patients with prostate cancer who would most appropriately be candidates for active surveillance (AS) according to current guidelines and to compare the results with those of conventional clinical assessment scoring systems, including the D'Amico, Epstein, and Cancer of the Prostate Risk Assessment (CAPRA) systems, on the basis of findings at prostatectomy.

MATERIALS AND METHODS

This institutional review board-approved HIPAA-compliant retrospectively designed study included 133 patients (mean age, 59.3 years) with a mean prostate-specific antigen level of 6.73 ng/mL (median, 4.39 ng/mL) who underwent multiparametric MR imaging at 3.0 T before radical prostatectomy. Informed consent was obtained from all patients. Patients were then retrospectively classified as to whether they would have met AS eligibility criteria or were better served by surgery. AS eligibility criteria for prostatectomy specimens were a dominant tumor smaller than 0.5 mL without Gleason 4 or 5 patterns or extracapsular or seminal vesicle invasion. Conventional clinical assessment scores (the D'Amico, Epstein, and CAPRA scoring systems) were compared with multiparametric MR imaging findings for predicting AS candidates. The level of significance of difference between scoring systems was determined by using the χ(2) test for categoric variables with the level of significance set at P < .05.

RESULTS

Among 133 patients, 14 were eligible for AS on the basis of prostatectomy results. The sensitivity, positive predictive value (PPV), and overall accuracy, respectively, were 93%, 25%, and 70% for the D'Amico system, 64%, 45%, and 88% for the Epstein criteria, and 93%, 20%, and 59% for the CAPRA scoring system for predicting AS candidates (P < .005 for all, χ(2) test), while multiparametric MR imaging had a sensitivity of 93%, a PPV of 57%, and an overall accuracy of 92% (P < .005).

CONCLUSION

Multiparametric MR imaging provides useful additional information to existing clinicopathologic scoring systems of prostate cancer and improves the assignment of treatment (eg, AS or active treatment).

Risk of Gleason grade inaccuracies in prostate cancer patients eligible for active surveillance

OBJECTIVE

To evaluate increases in Gleason grade because of sample bias after immediate rebiopsy or prostatectomy for patients considered active surveillance candidates by institutional protocol.

METHODS

A contemporary medical literature search was performed using PubMed. Series were included if the patients had no more than Gleason 6 prostate cancer score on initial biopsy and underwent a prostatectomy or rebiopsy within 6 months. Patient sets using neoadjuvant hormonal therapy or focal prostate treatment were excluded.

RESULTS

In patients who would have fallen into the D'Amico low-risk prostate cancer group, 42% were found to have an increase in the Gleason score: 32% resulting in grade ≥ 7 disease and 3% grade ≥ 8. For series that limited patients to the Epstein criteria, Gleason upgrades were 34%, 29%, and 2%, respectively. Of the 139 patients whose second tissue specimens were from a rebiopsy, 17% were found to have grade ≥ 7 disease, whereas only 1 patient had grade ≥ 8. There were no consistent multivariate analysis variables among the series to predict for an increase in Gleason score.

CONCLUSION

More than one third of the patients were found to have been undergraded based on their initial prostate biopsy. Therefore, 1 biopsy alone may not be sufficient to offer active surveillance as an option. Further exploration is necessary to better ensure low-risk disease before active surveillance.

International multicentre study examining selection criteria for active surveillance in men undergoing radical prostatectomy

Background:

The controversies concerning possible overtreatment of prostate cancer, highlighted by debate over PSA screening, have highlighted active surveillance (AS) as an alternative management option for appropriate men. Regional differences in the underlying prevalence of PSA testing may alter the pre-test probability for high-risk disease, which can potentially interfere with the performance of selection criteria for AS. In a multicentre study from three different countries, we examine men who were initially suitable for AS according to the Toronto and Prostate Cancer Research International: Active Surveillance (PRIAS) criteria, that underwent radical prostatectomy (RP) in regards to:1.the proportion of pathological reclassification(Gleason score ⩾7, ⩾pT3 disease),2.predictors of high-risk disease,3.create a predictive model to assist with selection of men suitable for AS.

Methods:

From three centres in the United Kingdom, Canada and Australia, data on men who underwent RP were retrospectively reviewed (n=2329). Multivariable logistic regression was performed to identify predictors of high-risk disease. A nomogram was generated by logistic regression analysis, and performance characterised by receiver operating characteristic curves.

Results:

For men suitable for AS according to the Toronto (n=800) and PRIAS (410) criteria, the rates for upgrading were 50.6, 42.7%, and upstaging 17.6, 12.4%, respectively. Significant predictors of high-risk disease were:•Toronto criteria: increasing age, cT2 disease, centre of diagnosis and number of positive cores.•PRIAS criteria: increasing PSA and cT2 disease.Cambridge had a high pT3a rate (26 vs 12%). To assist selection of men in the United Kingdom for AS, from the Cambridge data, we generated a nomogram predicting high-risk features in patients who meet the Toronto criteria (AUC of 0.72).

Conclusion:

The proportion of pathological reclassification in our cohort was higher than previously reported. Care must be used when applying the AS criteria generated from one population to another. With more stringent selection criteria, there is less reclassification but also fewer men who may benefit from AS.

Pathological findings at radical prostatectomy in patients initially managed by active surveillance: a comparative analysis

BACKGROUND

The purpose of our analysis was to determine if delays in treatment caused by active surveillance result in significant pathological changes when patients no longer meet the criteria on repeat biopsy and to study whether or not these changes may affect treatment outcomes.

METHODS

Out of 207 men who were on active surveillance, 47 (23%) no longer met the criteria after one of the repeat biopsies. Twenty-two underwent radical prostatectomy at our institution and formed the main group (Group 1) of this study. One hundred sixty-four patients met the criteria for active surveillance but underwent immediate surgery. Of these patients, we selected 38 (23%) with the lowest predicted biochemical recurrence-free survival. These patients formed the comparison group (Group 2). Pathological features as well as postoperative biochemical outcomes were compared between the groups.

RESULTS

Seven patients (32%) in Group 1 and four (11%) in Group 2 have predominantly high-grade cancer (i.e., ≥4/5 + 3) at pathology. The visually estimated percent of carcinoma was also higher in patients initially managed by active surveillance (median 12.5 vs. 5.0 in Groups 1 and 2, respectively, P = 0.009). Other pathological characteristics were similar in both groups. With limited duration of follow-up, postoperative biochemical recurrence-free survival did not differ significantly between the groups.

CONCLUSIONS

Our study has demonstrated that both tumor grade and volume may increase during active surveillance. However, the clinical significance of these changes with respect to the outcomes of delayed treatment remains to be established.

Biopsy features associated with prostate cancer progression in active surveillance patients: comparison of three statistical models

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Active surveillance is an established management option for patients with favourable-risk prostate cancer. However, about 25-30% of active surveillance patients demonstrate biopsy progression within the first 3-5 years of follow-up. Although several factors, such as the results of the diagnostic and surveillance biopsies, are known to be associated with the risk of progression, our ability to accurately predict this risk remains limited. Our analysis demonstrated that the overall number of positive cores in the diagnostic and first surveillance biopsies is strongly associated with the risk of progression in active surveillance patients. Furthermore, combined results of diagnostic and first surveillance biopsies provide more information about the probability of progression than they do separately. The most important variable affecting the progression-free survival was the overall number of cores positive for cancer. By 3 years of active surveillance, most of the patients who had four positive cores in the diagnostic and surveillance biopsies progressed, while those who had only one positive core had an excellent prognosis. These findings could be used to improve the accuracy of assessments of the prognosis of patients with low-risk prostate cancer and to help them make informed decisions about their treatment.

OBJECTIVE

To analyse the prognostic importance of information provided by the diagnostic biopsy, the first surveillance biopsy and a combination thereof to identify active surveillance patients with a particularly high risk of progression.

MATERIALS AND METHODS

The present study included 161 active surveillance patients who had at least two surveillance biopsies. The first surveillance biopsy was performed within 1 year of the diagnosis. Further surveillance biopsies usually took place every 1-2 years. Progression on the surveillance biopsy was defined as the presence of Gleason 4/5 cancer, > two positive cores or >20% involvement of any core. Cox proportional hazards regression analysis was used to examine the relationship between biopsy characteristics and progression. Three distinct statistical models were built using characteristics of diagnostic biopsies, surveillance biopsies, and a combination thereof. Harrell's c-index was used to quantify the predictive accuracy of each multivariate Cox model.

RESULTS

The median follow-up was 3.6 years; 46 (28.6%) patients progressed. In multivariate analysis the major factor associated with progression was the number of positive cores. The model based on the combined results of diagnostic and first surveillance biopsies was significantly more predictive than the models based on the individual results of each biopsy. Patients with four positive cores in the diagnostic and first surveillance biopsies had estimated 5-year progression rate of 100%.

CONCLUSION

The total number of positive cores in the diagnostic and first surveillance biopsies provides important information about the risk of prostate cancer progression in active surveillance patients.

Association of prostate cancer risk alleles with unfavourable pathological characteristics in potential candidates for active surveillance

OBJECTIVE

• To assess whether the carrier status of 35 risk alleles for prostate cancer (CaP) is associated with having unfavourable pathological features in the radical prostatectomy specimen in men with clinically low risk CaP who fulfil commonly accepted criteria as candidates for active surveillance.

PATIENTS AND METHODS

• We studied men of European ancestry with CaP who fulfilled the commonly accepted clinical criteria for active surveillance (T1c, prostate-specific antigen <10 ng/mL, biopsy Gleason ≤6, three or fewer positive cores, ≤50% tumour involvement/core) but instead underwent early radical prostatectomy. • We genotyped these men for 35 CaP risk alleles. We defined 'unfavourable' pathological characteristics to be Gleason ≥7 and/or ≥ pT2b in their radical prostatectomy specimen.

RESULTS

• In all, 263 men (median age 60 [46-72] years) fulfilled our selection criteria for active surveillance, and 58 of 263 (22.1%) were found to have 'unfavourable' pathological characteristics. • The frequencies of three CaP risk alleles (rs1447295 [8q24], P= 0.004; rs1571801 [9q33.2], P= 0.03; rs11228565 [11q13], P= 0.02) were significantly higher in men with 'unfavourable' pathological characteristics. • Two other risk alleles were proportionately more frequent (rs10934853 [3q21], P= 0.06; rs1859962 [17q24], P= 0.07) but did not achieve nominal statistical significance. • Carriers of any one of the significantly over-represented risk alleles had twice the likelihood of unfavourable tumour features (P= 0.03), and carriers of any two had a sevenfold increased likelihood (P= 0.001). • Receiver-operator curve analysis demonstrated an area under the curve of 0.66, suggesting that the number of single nucleotide polymorphisms carried provided discrimination between men with 'favourable' and 'unfavourable' tumour features in their prostatectomy specimen.

CONCLUSION

• In potential candidates for active surveillance, certain CaP risk alleles are more prevalent in patients with 'unfavourable' pathological characteristics in their radical prostatectomy specimen.