Role of prostate specific antigen and immediate confirmatory biopsy in predicting progression during active surveillance for low risk prostate cancer

Active Surveillance for Taiwanese Men with Localized Prostate Cancer: Intermediate-Term Outcomes and Predictive Factors

PURPOSE

Active surveillance (AS) is one of the management options for patients with low-risk and select intermediate-risk prostate cancer (PC). However, factors predicting disease reclassification and conversion to active treatment from a large population of pure Asian cohorts regarding AS are less evaluated. This study investigated the intermediate-term outcomes of patients with localized PC undergoing AS.

MATERIALS AND METHODS

This cohort study enrolled consecutive men with localized non-high-risk PC diagnosed in Taiwan between June 2012 and Jan 2023. The study endpoints were disease reclassification (either pathological or radiographic progression) and conversion to active treatment. The factors predicting endpoints were evaluated using the Cox proportional hazards model.

RESULTS

A total of 405 patients (median age: 67.2 years) were consecutively enrolled and followed up with a median of 64.6 months. Based on the National Comprehensive Cancer Network (NCCN) risk grouping, 70 (17.3%), 164 (40.5%), 140 (34.6%), and 31 (7.7%) patients were classified as very low-risk, low-risk, favorable-intermediate risk, and unfavorable intermediate-risk PC, respectively. The 5-year reclassification rates were 24.8%, 27.0%, 18.6%, and 25.3%, respectively. The 5-year conversion rates were 20.4%, 28.8%, 43.6%, and 37.8%, respectively. A prostate-specific antigen density (PSAD) of ≥0.15 ng/mL² predicted reclassification (hazard ratio [HR] 1.84, 95% confidence interval [CI] 1.17-2.88) and conversion (HR 1.56, 95% CI 1.05-2.31). A maximal percentage of cancer in positive cores (MPCPC) of ≥15% predicted conversion (15% to <50%: HR 1.41, 95% CI 0.91-2.18; ≥50%: HR 1.97, 95% CI 1.1453-3.40) compared with that of <15%. A Gleason grade group (GGG) of 3 tumor also predicted conversion (HR 2.69, 95% CI 1.06-6.79; GGG 3 vs 1). One patient developed metastasis, but none died of PC during the study period (2,141 person-years).

CONCLUSIONS

AS is a viable option for Taiwanese men with non-high-risk PC, in terms of reclassification and conversion. High PSAD predicted reclassification, whereas high PSAD, MPCPC, and GGG predicted conversion.

Low-risk prostate lesions: An evidence review to inform discussion on losing the "cancer" label

BACKGROUND

Active surveillance (AS) mitigates harms from overtreatment of low-risk prostate lesions. Recalibration of diagnostic thresholds to redefine which prostate lesions are considered "cancer" and/or adopting alternative diagnostic labels could increase AS uptake and continuation.

METHODS

We searched PubMed and EMBASE to October 2021 for evidence on: (1) clinical outcomes of AS, (2) subclinical prostate cancer at autopsy, (3) reproducibility of histopathological diagnosis, and (4) diagnostic drift. Evidence is presented via narrative synthesis.

RESULTS

AS: one systematic review (13 studies) of men undergoing AS found that prostate cancer-specific mortality was 0%-6% at 15 years. There was eventual termination of AS and conversion to treatment in 45%-66% of men. Four additional cohort studies reported very low rates of metastasis (0%-2.1%) and prostate cancer-specific mortality (0%-0.1%) over follow-up to 15 years. Overall, AS was terminated without medical indication in 1%-9% of men. Subclinical reservoir: 1 systematic review (29 studies) estimated that the subclinical cancer prevalence was 5% at <30 years, and increased nonlinearly to 59% by >79 years. Four additional autopsy studies (mean age: 54-72 years) reported prevalences of 12%-43%. Reproducibility: 1 recent well-conducted study found high reproducibility for low-risk prostate cancer diagnosis, but this was more variable in 7 other studies. Diagnostic drift: 4 studies provided consistent evidence of diagnostic drift, with the most recent (published 2020) reporting that 66% of cases were upgraded and 3% were downgraded when using contemporary diagnostic criteria compared to original diagnoses (1985-1995).

CONCLUSIONS

Evidence collated may inform discussion of diagnostic changes for low-risk prostate lesions.

Validating the total cancer location density metric for stratifying patients with low-risk localized prostate cancer at higher risk of grade group reclassification while on active surveillance

PURPOSE

To validate a previously proposed prognostic metric, Total Cancer Location (TCLo) density, in a contemporary cohort of men with grade group (GG) 1 prostate cancer (PCa) on active surveillance (AS).

METHODS

We evaluated 123 patients who entered AS with maximum GG1 PCa at diagnostic and/or confirmatory biopsy. TCLo was defined as the total number of PCa locations identified on both biopsy sessions. TCLo density was calculated as TCLo / prostate volume [ml]. Primary endpoint was progression-free survival (PFS), defined as time from confirmatory biopsy to grade group reclassification (GGR) on repeat biopsy or prostatectomy. Optimal cut-point for TCLo density was predefined in a previously reported cohort and applied to this contemporary cohort. Kaplan-Meier and multivariable Cox regression analysis were used to estimate the association of predictors with PFS.

RESULTS

During median follow-up of 7.8 years, (IQR 7.3-8.2) 34 men had GGR. Using previously defined cut-points, PFS at 5-years was 60% (95% CI: 44%-81%) vs. 89% (95% CI: 83%-96%) in men with high (≥0.06 ml^-1) vs. low (<0.06 ml^-1) TCLo density, and 63% (95% CI: 48%-82%) vs. 90% (95% CI: 83%-96%) in men with high (≥3) vs. low (≤2) TCLo (log-rank test: P < 0.0001, respectively). Adjusting for age, prostate volume, percent of positive cores and PSA, both higher TCLo density (HR [per 0.01 ml^-1 increase]: 1.18, 95% CI: 1.05-1.33, P = 0.005) and TCLo (HR: 1.69, 95% CI: 1.20-2.38, P = 0.002) were associated with shorter PFS.

CONCLUSION

The previously suggested prognostic value of TCLo density was confirmed in this validation cohort. TCLo alone performed similarly well. Patients with high TCLo density (≥0.06 ml^-1) or TCLo (>2) were at greater risk of GGR while on AS. With external validation, these metric may help guide risk-adapted surveillance protocols.

Low-volume grade group 2 prostate cancer candidates for active surveillance: a radical prostatectomy retrospective analysis

OBJECTIVE

Guidelines support considering selected men with ISUP grade group (GG) 2 prostate cancer for active surveillance (AS). We assessed the association of clinical variables with unfavorable pathology at radical prostatectomy in low-volume GG 2 prostate cancer on biopsy in a retrospective cohort.

MATERIALS AND METHODS

This was a retrospective analysis of 378 men with low-volume (≤ 2 cores) GG 2 localized prostate cancer who underwent prostatectomy at a single tertiary cancer center. Multivariable logistic regression of unfavorable pathology, upgrading to ≥ T3, or GG ≥ 3 was performed in relation to clinical factors, common variables used in AS in GG 1 and percentage Gleason 4 at biopsy. We compared the performance of potential variables with commonly used combined AS restrictions in GG 1 prostate cancer.

RESULTS

In total, 128/378 (34%) men had unfavorable pathology at radical prostatectomy. On multivariable analysis, > 5% Gleason pattern 4 was independently associated with an increased risk of GG ≥ 3. A maximum percentage core involvement > 50% was independently associated with an increased risk of pT-stage ≥ 3 and unfavorable pathology. Restriction to patients with ≤ 5% Gleason 4 decreased the upgrading of both unfavorable pathology (OR = 0.62, p = 0.041) and GG ≥ 3 (OR = 0.17, p = 0.0007) compared to the full cohort, while restriction to those with ≤ 50% of max core involvement did not.

CONCLUSION

In low-volume GG 2, the percentage of Gleason 4 of ≤ 5% was the strongest predictor in reducing upgrading at final pathology. This easily available pathological descriptor could be used to guide urologists and patients when considering AS in this setting.

Can multi-parametric magnetic resonance imaging and prostate-specific antigen density accurately stratify patients prior to prostate biopsy?

Objective:

This study examines the diagnostic accuracy of multi-parametric magnetic resonance imaging (mpMRI) in a high-volume centre to potentially stratify patients prior to prostate biopsy.

Methods:

All biopsy naïve patients who had mpMRI prostate and transperineal biopsy of prostate (TPBx) in 2017 and 2018 were included. There were no exclusion criteria. All patients, regardless of the mpMRI result, underwent systematic template biopsy under general anaesthesia with cognitive target biopsy if indicated. Clinicopathological data were extracted from medical records. The primary outcome was the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of mpMRI prostate in the detection of prostate cancer (PCa) compared with template TPBx.

Results:

In total, 140 patients were included. Overall, 57.1% had a positive biopsy. A higher Prostate Imaging-Reporting and Data Systems (PI-RADS) score was associated with a higher risk of diagnosing clinically significant PCa (International Society of Urological Pathology (ISUP) ⩾ 2) ( p < 0.001). The sensitivity, specificity, NPV, and PPV of mpMRI in detecting clinically significant PCa with a PI-RADS ⩾ 3 lesion, was 95% (95% confidence interval (CI) 83.0–99.3%), 41% (95% CI 31.3–51.3%), 95.3% (95% CI 84.2–99.4%) and 39.2% (95% CI 29.4–49.6%), respectively. Combining this with prostate-specific antigen density (PSAD) of <0.15 further improved the NPV to 100% (86.3–100). Binomial logistic regression to understand the effects of PSA, DRE and PI-RADS score on predicting clinically significant PCa (ISUP ⩾ 2) found increasing PSA (odds ratio (OR) 1.06, (95% CI 1.00–1.11, p = 0.022)) and PI-RADS (OR 3.17, (95% CI 1.94–5.18, p < 0.001)) to be significant predictors. Malignant DRE was not a significant predictor ( p = 0.087).

Conclusion:

This study demonstrates that the high sensitivity and NPV of mpMRI combined with PSAD may play a pivotal role in stratifying men for prostate biopsy and help avoid biopsy and its associated morbidity in select patients.

Level of Evidence:

2b (Oxford Centre for Evidence-Based Medicine: Levels of Evidence)

Association between previous negative biopsies and lower rates of progression during active surveillance for prostate cancer

Purpose

To test any-cause discontinuation and ISUP GG upgrading rates during Active Surveillance (AS) in patients that underwent previous negative biopsies (PNBs) before prostate cancer (PCa) diagnosis vs. biopsy naive patients.

Methods

Retrospective analysis of 961 AS patients (2008–2020). Three definitions of PNBs were used: (1) PNBs status (biopsy naïve vs. PNBs); (2) number of PNBs (0 vs. 1 vs. ≥ 2); (3) histology at last PNB (no vs. negative vs. HGPIN/ASAP). Kaplan–Meier plots and multivariable Cox models tested any-cause and ISUP GG upgrading discontinuation rates.

Results

Overall, 760 (79.1%) vs. 201 (20.9%) patients were biopsy naïve vs. PNBs. Specifically, 760 (79.1%) vs. 138 (14.4%) vs. 63 (6.5%) patients had 0 vs. 1 vs. ≥ 2 PNBs. Last, 760 (79.1%) vs. 134 (13.9%) vs. 67 (7%) patients had no vs. negative PNB vs. HGPIN/ASAP. PNBs were not associated with any-cause discontinuation rates. Conversely, PNBs were associated with lower rates of ISUP GG upgrading: (1) PNBs vs. biopsy naïve (HR:0.6, p = 0.04); (2) 1 vs. 0 PNBs (HR:0.6, p = 0.1) and 2 vs. 0 PNBs, (HR:0.5, p = 0.1); (3) negative PNB vs. biopsy naïve (HR:0.7, p = 0.3) and HGPIN/ASAP vs. biopsy naïve (HR:0.4, p = 0.04). However, last PNB ≤ 18 months (HR:0.4, p = 0.02), but not last PNB > 18 months (HR:0.8, p = 0.5) were associated with lower rates of ISUP GG upgrading.

Conclusion

PNBs status is associated with lower rates of ISUP GG upgrading during AS for PCa. The number of PNBs and time from last PNB to PCa diagnosis (≤ 18 months) appear also to be critical for patient selection.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-022-03983-8.

Diagnostic Accuracy of Contemporary Selection Criteria in Prostate Cancer Patients Eligible for Active Surveillance: A Bayesian Network Meta-Analysis

Background

Several active surveillance (AS) criteria have been established to screen insignificant prostate cancer (insigPCa, defined as organ confined, low grade and small volume tumors confirmed by postoperative pathology). However, their comparative diagnostic performance varies. The aim of this study was to compare the diagnostic accuracy of contemporary AS criteria and validate the absolute diagnostic odds ratio (DOR) of optimal AS criteria.

Methods

First, we searched Pubmed and performed a Bayesian network meta-analysis (NMA) to compare the diagnostic accuracy of contemporary AS criteria and obtained a relative ranking. Then, we searched Pubmed again to perform another meta-analysis to validate the absolute DOR of the top-ranked AS criteria derived from the NMA with two endpoints: insigPCa and favorable disease (defined as organ confined, low grade tumors). Subgroup and meta-regression analyses were conducted to identify any potential heterogeneity in the results. Publication bias was evaluated.

Results

Seven eligible retrospective studies with 3,336 participants were identified for the NMA. The diagnostic accuracy of AS criteria ranked from best to worst, was as follows: Epstein Criteria (EC), Yonsei criteria, Prostate Cancer Research International: Active Surveillance (PRIAS), University of Miami (UM), University of California-San Francisco (UCSF), Memorial Sloan-Kettering Cancer Center (MSKCC), and University of Toronto (UT). I² = 50.5%, and sensitivity analysis with different insigPCa definitions supported the robustness of the results. In the subsequent meta-analysis of DOR of EC, insigPCa and favorable disease were identified as endpoints in ten and twenty-two studies, respectively. The pooled DOR for insigPCa and favorable disease were 0.44 (95%CI, 0.31–0.58) and 0.66 (95%CI, 0.61–0.71), respectively. According to a subgroup analysis, the DOR for favorable disease was significantly higher in US institutions than that in other regions. No significant heterogeneity or evidence of publication bias was identified.

Conclusions

Among the seven AS criteria evaluated in this study, EC was optimal for positively identifying insigPCa patients. The pooled diagnostic accuracy of EC was 0.44 for insigPCa and 0.66 when a more liberal endpoint, favorable disease, was used.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/], PROSPERO [CRD42020157048].

The impact of pretreatment PSA on risk stratification in men with Gleason 6 prostate cancer: Implications for active surveillance

BACKGROUND

There are limited data to support the safety of active surveillance in men with favorable-intermediate risk prostate cancer due only to a prostate specific antigen (PSA) above 10 ng/ml. We therefore evaluated the impact of pretreatment PSA on risk-stratification in men with Gleason 6 prostate cancer.

METHODS

We identified men aged 18 to 75 with cT1-2cN0cM0, pre-treatment PSA < 20 ng/ml, Gleason 6 prostate cancer diagnosed from 2010 to 2016 in the National Cancer Database who underwent radical prostatectomy. The associations of patient and disease features with Gleason score upgrading or adverse pathologic features at prostatectomy were evaluated using logistic regression. To evaluate for non linear relationships between PSA and each outcome, we examined predicted marginal event rates standardized for baseline characteristics with PSA modeled using restricted cubic splines RESULTS: A total of 75,566 patients were included in the cohort. In unadjusted analyses, patients with pretreatment PSA ≥ 10 ng/ml had higher rates of Gleason core upgrading (58.8% vs. 47.9%; P< 0.001) and adverse pathologic features (19.7% vs. 10.0%; P< 0.001) compared to patients with PSA < 10 ng/ml. In multivariable analyses, PSA ≥ 10 ng/ml was associated with statistically significantly increased risks of Gleason score upgrading (OR 1.47;95%CI 1.39 - 1.55) and adverse pathologic features (OR 2.15;95%CI 2.01 - 2.30). When modeled as a non linear continuous covariate, PSA was associated with increased adjusted rates of Gleason score upgrading and adverse pathologic features without a clear dichotomization at a threshold of 10 ng/ml.

CONCLUSION

Higher pretreatment PSA was independently associated with increased risks of Gleason score upgrading and adverse pathologic features at prostatectomy. Flexible modeling of the relationship between PSA and each outcome did not support dichotomization at a threshold of 10 ng/ml. These results can be used to improve patient risk-stratification for active surveillance.

The clinical impact of strict criteria for active surveillance of prostate cancer in Korean population: Results from a prospective cohort

Purpose

To evaluate the clinical impact of strict selection criteria for active surveillance (AS) of prostate cancer in a Korean population.

Materials and Methods

A single-center, prospectively collected AS cohort from December 2016 to February 2019 was used. Following pre-determined criteria, patients were categorized into “strict AS” and “non-strict AS” groups. Clinicopathological progression-free survival (PFS) and treatment-free survival (TFS) of the two groups were compared using the Kaplan–Meier curve and log-rank test. Age-adjusted hazard ratios for clinicopathological progression was calculated using Cox proportional regression analysis.

Results

Of 54 eligible patients, 25 and 29 were assigned to “strict AS” and “non-strict AS,” respectively. Clinicopathological progression and definitive treatment rates were 24.0% (6 of 25 patients) vs. 51.7% (15 of 29 patients) and 32.0% (8 of 25 patients) vs. 62.1% (18 of 29 patients) in “strict AS” and “non-strict AS” groups. Progress to high-risk cancer (pathologic T3 or surgical Gleason Grade 2 over) in radical prostatectomy was higher in “non-strict AS” than “strict AS”. PFS (mean 34.6±2.9 mo vs. 22.6±2.7 mo; p=0.025) and TFS (mean 31.8±3.2 mo vs. 19.6±2.4 mo; p=0.018) favor the “strict AS” group than “non-strict AS” group. Age-adjusted hazard ratio for clinicopathological progression of strict criteria was 0.36 (95% confidence interval, 0.14–0.94; p=0.04).

Conclusions

PFS and TFS were better in the “strict AS” group than in the “non-strict AS” group. This finding should be informed to relevant patients during decision making and considered in Korean guidelines.

Advances in the selection of patients with prostate cancer for active surveillance

Early identification and management of prostate cancer completely changed with the discovery of prostate-specific antigen. However, improved detection has also led to overdiagnosis and consequently overtreatment of patients with low-risk disease. Strategies for the management of patients using active surveillance - the monitoring of clinically insignificant disease until intervention is warranted - were developed in response to this issue. The success of this approach is critically dependent on the accurate selection of patients who are predicted to be at the lowest risk of prostate cancer mortality. The Epstein criteria for clinically insignificant prostate cancer were first published in 1994 and have been repeatedly validated for risk-stratification and selection for active surveillance over the past few decades. Current active surveillance programmes use modified criteria with 30-50% of patients receiving treatment at 10 years. Nonetheless, tools for prostate cancer diagnosis have continued to evolve with improvements in biopsy format and targeting, advances in imaging technologies such as multiparametric MRI, and the identification of serum-, tissue- and urine-based biomarkers. These advances have the potential to further improve the identification of men with low-risk disease who can be appropriately managed using active surveillance.

Update on Multiparametric Prostate MRI During Active Surveillance: Current and Future Trends and Role of the PRECISE Recommendations

Active surveillance for low-to-intermediate risk prostate cancer is a conservative management approach that aims to avoid or delay active treatment until there is evidence of disease progression. In recent years, multiparametric MRI (mpMRI) has been increasingly used in active surveillance and has shown great promise in patient selection and monitoring. This has been corroborated by publication of the Prostate Cancer Radiologic Estimation of Change in Sequential Evaluation (PRECISE) recommendations, which define the ideal reporting standards for mpMRI during active surveillance. The PRECISE recommendations include a system that assigns a score from 1 to 5 (the PRECISE score) for the assessment of radiologic change on serial mpMRI scans. PRECISE scores are defined as follows: a score of 3 indicates radiologic stability, a score of 1 or 2 denotes radiologic regression, and a score of 4 or 5 indicates radiologic progression. In the present study, we discuss current and future trends in the use of mpMRI during active surveillance and illustrate the natural history of prostate cancer on serial scans according to the PRECISE recommendations. We highlight how the ability to classify radiologic change on mpMRI with use of the PRECISE recommendations helps clinical decision making.

Concordance of confirmatory prostate biopsy in active surveillance with national guidelines: An analysis from the multi-institutional PURC cohort

PURPOSE

National Comprehensive Cancer Network (NCCN) guidelines recommend confirmatory biopsy within 12 months of active surveillance (AS) enrollment. With <10 cores on initial biopsy, re-biopsy should occur within 6 months. Our objective was to determine if patients on AS within practices in the Pennsylvania Urologic Regional Collaborative (PURC) receive guideline concordant confirmatory biopsies.

MATERIALS AND METHODS

Within PURC, a prospective collaborative of diverse urology practices in Pennsylvania and New Jersey, we identified men enrolled in AS after first biopsy, analyzing time to re-biopsy and factors associated with various intervals of re-biopsy.

RESULTS

In total, 1,047 patients were enrolled in AS for a minimum of 12 months after initial biopsy. Four hundred seventy-seven (45%) underwent second biopsy at 1 of the 9 PURC practices. The number of patients undergoing re-biopsy within 6 months, 6 to 12 months, 12 to 18 months, and >18 months was 71 (14%), 218 (45.7%), 134 (28%), and 54 (11%), respectively. Sixty percent underwent confirmatory biopsy within 12 months. On multivariate analysis, re-biopsy interval was associated with number of positive cores, perineural invasion, and practice ID (all P < 0.05). Adjusted multivariable regression did not identify factors predictive of re-biopsy interval.

CONCLUSION

Of patients who underwent confirmatory biopsy at PURC practices, 60.5% were within 12 months per NCCN guidelines. This suggests area for improvement in guideline adherence after enrollment in AS. All practices that offer AS should periodically perform similar analyses to monitor their performance. In an era of value-based care, adherence to guideline based active surveillance practices may eventually comprise national quality metrics affecting provider reimbursement.

A Narrative Overview of Active Surveillance for Clinically Localised Prostate Cancer

BACKGROUND

-Active surveillance (AS) is a strategy employed as an alternative to immediate standard active treatments for patients with low-risk localised prostate cancer (PCa). Active treatments such as radical prostatectomy and radiotherapy are associated with significant adverse effects which impair quality of life. The majority of patients with low-risk PCa undergo a slow and predictable course of cancer growth and do not require immediate curative treatment. AS provides a means to identify and monitor patients with low-risk PCa through regular PSA testing, imaging using MRI scans and regular repeat prostate biopsies. These measures enable the identification of progression, or increase in cancer extent or aggressiveness, which necessitates curative treatment. Alternatively, some patients may choose to leave AS to pursue curative interventions due to anxiety. The main benefit of AS is the avoidance of unnecessary radical treatments for patients at the early stages of the disease, hence avoiding over-treatment, whilst identifying those at risk of progression to be treated actively. The objective of this article is to provide a narrative summary of contemporary practice regarding AS based on a review of the available evidence base and clinical practice guidelines. Elements of discussion include the clinical effectiveness and harms of AS, what AS involves for healthcare professionals, and patient perspectives. The pitfalls and challenges for healthcare professionals are also discussed.

DATA SOURCES

We consulted international guidelines, collaborative studies and seminal prospective studies on AS in the management of clinically localised PCa.

CONCLUSION

AS is a feasible alternative to radical treatment options for low-risk PCa, primarily as a means of avoiding over-treatment, whilst identifying those who are at risk of disease progression for active treatment. There is emerging data demonstrating the long-term safety of AS as an oncological management strategy. Uncertainties remain regarding variation in definitions, criteria, thresholds and the most effective types of diagnostic interventions pertaining to patient selection, monitoring and reclassification. Efforts have been made to standardise the practice and conduct of AS. As data from high-quality prospective comparative studies mature, the practice of AS will continue to evolve.

IMPLICATIONS FOR NURSING PRACTICE

The practice of AS involves a multi-disciplinary team of healthcare professionals consisting of nurses, urologists, oncologists, pathologists and radiologists. Nurses play a prominent role in managing AS programmes, and are closely involved in patient selection and recruitment, counselling, organising and administering diagnostic interventions including prostate biopsies, and ensuring patients' needs are being met throughout the duration of AS.

Predicting Insignificant Prostate Cancer: Analysis of the Pathological Outcomes of Candidates for Active Surveillance according to the Pre-International Society of Urological Pathology (Pre-ISUP) 2014 Era Versus the Post-ISUP2014 Era

Purpose

To analyze the difference in the prediction accuracy with an active surveillance (AS) protocol between two eras (pre-International Society of Urological Pathology [pre-ISUP]-2014 vs. post-ISUP2014).

Materials and Methods

We retrospectively analyzed 118 candidates for AS who underwent radical prostatectomy between 2009 and 2017. We divided our patients into two groups (group 1 [n=57], operation date 2009–2015; group 2 [n=61], operation date 2016–2017). Pathologic slides in group 1 were reviewed to distinguish men with cribriform pattern (CP) because the determination of Gleason scores in old era had been based on pre-ISUP2014 classification. Postoperative outcomes in the two eras were analyzed twice: first, all men in group 1 vs. group 2; second, the remaining men after excluding those with CPs in group 1 vs. group 2.

Results

The proportion of men with insignificant prostate cancer (iPCa) was significantly lower in group 1 than in group 2 (36.8% vs. 57.4%, p=0.040). After excluding 11 men with CPs from group 1, those remaining (46 men) were compared again with group 2. In this analysis, the proportion of men with iPCa was similar between the two groups (old vs. contemporary era: 41.3% vs. 57.4%, p=0.146). Nine of 11 men with CP had violated the criteria for iPCa in the earlier comparison.

Conclusions

The accuracy of the AS protocol has been affected by the coexistence of CPs and pure Gleason 6 tumors in the pre-ISUP2014 era. We suggest to use only contemporary (post-ISUP2014) data to analyze the accuracy with AS protocols in future studies.

Active Surveillance of Prostate Cancer Using Multiparametric Magnetic Resonance Imaging: A Review of the Current Role and Future Perspectives

Clinically, active surveillance involves continuous monitoring of patients who may be at risk for disease. Patients with low-grade and early-stage prostate cancer may benefit from active surveillance, rather than undergoing surgical and medical treatments that are associated with side effects. In these cases, the role of active surveillance is to ensure that there is no progression of the disease. However, active surveillance may be associated with a risk of under-diagnosis. Previously, the assignment of risk categories and patient monitoring were based on digital rectal examination, transrectal prostate biopsy, and monitoring of serum levels of prostate-specific antigen (PSA). Multiparametric magnetic resonance imaging (MRI) of the prostate gland has an estimated negative predictive value of 95% for the detection of prostate cancer, which makes this an effective imaging method for targeting biopsies and for monitoring patients over time. Also, multiparametric MRI-guided biopsy at the initial stage of the risk stratification for patients who are newly diagnosed with prostate cancer may reduce the number of underdiagnosed patients, improve long-term patient prognosis, and reduce the number of patients who are overtreated, which may reduce healthcare costs and reduce treatment morbidity. For these reasons, multiparametric MRI has become an accepted monitoring tool in patients who are enrolled in active surveillance programs. This review aims to present the current status of the use of multiparametric MRI in active surveillance of prostate cancer and to discuss future perspectives, supported by recent literature.

Confirmatory multiparametric magnetic resonance imaging at recruitment confers prolonged stay in active surveillance and decreases the rate of upgrading at follow-up

BACKGROUND

To understand the value of multiparametric magnetic resonance imaging (mpMRI) and targeted biopsies at recruitment on active surveillance (AS) outcomes.

MATERIALS AND METHODS

This retrospective single-center study enrolled two cohorts of 206 and 310 patients in AS. The latter group was submitted to mpMRI and targeted biopsies at recruitment. Kaplan-meier curves quantified progression-free survival (PFS) and Bioptic-PFS (B-PFS: no upgrading or >3 positive cores) in the two cohorts. Cox-regression analyses tested independent predictors of PFS and B-PFS. In patients submitted to radical prostatectomy (RP) after AS, significant cancer (csPCa) was defined as: GS ≥ 4 + 3 and/or pT ≥ 3a and/or pN+ . Logistic-regression analyses predicted csPCa at RP.

RESULTS AND LIMITATIONS

Median time follow-up and median time of persistence in AS were 46 (24-70) and 36 (23-58) months, respectively. Patients submitted to mpMRI at AS begin, showed greater PFS at 1- (98% vs. 91%), 3- (80% vs. 57%), and 5-years (70% vs. 35%) follow-up, respectively (all p < 0.01). At Cox-regression analysis only confirmatory mpMRI± targeted biopsy (HR: 0.3; 95% CI 0.2-0.5; p < 0.01) at AS begin was an independent predictor of PFS. Globally, 50 (16%) vs. 128 (62%) and 26 (8.5%) vs. 64 (31%) [all p < 0.01] men in the two groups experienced any-cause and bioptic AS discontinuation, respectively. Patients submitted to confirmatory mpMRI experienced greater 1-(98% vs. 93%), 3-(90% vs. 75%), and 5-years (83% vs. 56%) B-PFS, respectively (all p < 0.01). At Cox-regression analysis, mpMRI±-targeted biopsy at AS begin was associated with B-PFS (HR: 0.3; 95% CI 0.2-0.6; p < 0.01). No differences were recorded in csPCa rates between the two groups (22% vs. 28%; p = 0.47). Limitations of the study are the single-center retrospective nature and the absence of long-term follow-up.

CONCLUSIONS

Confirmatory mpMRI±-targeted biopsies are associated with higher PFS and B-PFS during AS. However, a non-negligible percentage of patients experience csPCa after switching to active treatment.

Prostate cancer adverse pathology reclassification in patients undergoing active surveillance in a long-term follow-up series

BACKGROUND

Active surveillance (AS) has become a valid option for patients with a very low risk of prostate cancer (PC) with a widespread application. There are still a few series, with a medium follow-up longer than 5 years, reporting data on pathological upgrading. The objective is to evaluate the changes in surveillance biopsies of patients with low-risk PC in a long-term follow-up and determine if a longer stay in AS could involve worse pathological findings.

MATERIALS AND METHODS

A retrospective analysis of our institutional database of patients with PC undergoing AS during 2004 to 2018 was performed. The inclusion criteria were prostate-specific antigen (PSA) ≤ 10 ng/mL, Gleason grade 1 and T1c/T2a. Patients were assessed by serum PSA level and digital rectal examination at 6-month intervals. Transrectal ultrasound-guided prostate biopsies were performed during the first year of follow-up, and every 2 or 3 years thereafter. The pathology details of biopsies were analyzed and compared with the current series on AS.

RESULTS

Three-hundred nineteen patients undergoing AS were evaluated with a median follow-up of 5.3 years and a mean age of 67.4 years. Sixty-three patients did not meet all the criteria to be considered low-risk PC but were included in the analysis. Overall, 128 patients (40.1%) underwent active treatment (84.7% of them due to pathological progression in surveillance biopsies). The proportion of patients with a reported upgrading ranged between 19.4% and 35.3%, although only the fourth biopsy showed an upgrading proportion of over 30%. Limitations include the retrospective design of the study and the existence of different protocols between other cohorts that make it difficult to compare their results.

CONCLUSIONS

For patients who remained in surveillance the percentage of upgrading increased slightly with the time, being more frequent after the third-surveillance biopsy. These findings support the importance of extending surveillance biopsies for patients who remain candidates for curative treatment.

Tumor burden and location as prognostic factors in patients treated by iodine seed implant brachytherapy for localized prostate cancers

Background

Iodine seed implant brachytherapy is indicated for low risk and selected favorable intermediate risk prostate cancers. A percentage of positive biopsies > 50% is usually considered as a contra-indication, and the tumor location could also influence the treatment efficacy. We studied the association of the percentage of positive biopsy cores, and tumor location, with progression-free survival.

Methods

Among the 382 patients treated at our center by permanent implant iodine seed brachytherapy for a localized prostate cancer between 2006 and 2013, 282 had accessible detailed pathology reports, a minimum follow-up of 6 months, and were included. Progression was defined as a biochemical, local, nodal, or distant metastatic relapse. We studied cancer location on biopsies (base, midgland or apex of the prostate) and percentage of positive biopsy cores, as well as potential confounders (pre-treatment PSA, tumor stage, Gleason score, risk group according to D’Amico’s classification modified by Zumsteg, adjunction of androgen deprivation therapy, and dosimetric data).

Results

Most patients (197; 69.9%) had a low risk, 67 (23.8%) a favorable intermediate risk, 16 (5.7%) an unfavorable intermediate risk, and 1 (0.3%) a high-risk prostate cancer. An involvement of the apex was found for 131 patients (46,5%), of the midgland for 149 (52,8%), and of the base for 145 (51,4%). The median percentage of positive biopsy cores was 17% [3–75%]. The median follow-up was 64 months [12–140]. Twenty patients (7%) progressed: 4 progressions (20%) were biochemical only, 7 (35%) were prostatic or seminal, 6 (30%) were nodal, and 3 (15%) were metastatic. The median time to failure was 39.5 months [9–108]. There were more Gleason scores ≥7 among patients who progressed (40% vs 19%; p = 0.042). None of the studied covariates (including tumor location, and percentage of positive biopsy cores), were significantly associated with progression-free survival. The risk group showed a trend towards an association (p = 0.055).

Conclusions

Brachytherapy is an efficient treatment (5-year control rate of 93%) for patients carefully selected with classical criteria. The percentage and location of positive biopsies were not significantly associated with progression-free survival. A Gleason score ≥ 7 was more frequent in case of progression.

Long-Term Outcomes of Active Surveillance for Prostate Cancer: The Memorial Sloan Kettering Cancer Center Experience

PURPOSE

We report oncologic outcomes for men with Grade Group 1 prostate cancer managed with active surveillance at a tertiary cancer center.

MATERIALS AND METHODS

A total of 2,907 patients were managed with active surveillance between 2000 and 2017, of whom 2,664 had Grade Group 1 disease. Patients were recommended confirmatory biopsy to verify eligibility and were followed semiannually with prostate specific antigen, digital rectal examination and review of symptoms. Magnetic resonance imaging was increasingly used in recent years. Biopsy was repeated every 2 to 3 years or after a sustained prostate specific antigen increase or changes in magnetic resonance imaging/digital rectal examination. The Kaplan-Meier method was used to estimate probabilities of treatment, progression and development of metastasis.

RESULTS

Median patient age at diagnosis was 62 years. For men with Grade Group 1 prostate cancer the treatment-free probability at 5, 10 and 15 years was 76% (95% CI 74-78), 64% (95% CI 61-68) and 58% (95% CI 51-64), respectively. At 5, 10 and 15 years there were 1,146, 220 and 25 men at risk for metastasis, respectively. Median followup for those without metastasis was 4.3 years (95% CI 2.3-6.9). Distant metastasis developed in 5 men. Upon case note review only 2 of these men were deemed to have disease that could have been cured on immediate treatment. The risk of distant metastasis was 0.6% (95% CI 0.2-2.0) at 10 years.

CONCLUSIONS

Active surveillance is a safe strategy over longer followup for appropriately selected patients with Grade Group 1 disease following a well-defined monitoring plan.

Predicting Biopsy Outcomes During Active Surveillance for Prostate Cancer: External Validation of the Canary Prostate Active Surveillance Study Risk Calculators in Five Large Active Surveillance Cohorts

BACKGROUND

Men with prostate cancer (PCa) on active surveillance (AS) are followed through regular prostate biopsies, a burdensome and often unnecessary intervention, not without risks. Identifying men with at a low risk of disease reclassification may help reduce the number of biopsies.

OBJECTIVE

To assess the external validity of two Canary Prostate Active Surveillance Study Risk Calculators (PASS-RCs), which estimate the probability of reclassification (Gleason grade ≥7 with or without >34% of biopsy cores positive for PCa) on a surveillance biopsy, using a mix of months since last biopsy, age, body mass index, prostate-specific antigen, prostate volume, number of prior negative biopsies, and percentage (or ratio) of positive cores on last biopsy.

DESIGN, SETTING, AND PARTICIPANTS

We used data up to November 2017 from the Movember Foundation's Global Action Plan (GAP3) consortium, a global collaboration between AS studies.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

External validity of the PASS-RCs for estimating reclassification on biopsy was assessed by calibration, discrimination, and decision curve analyses.

RESULTS AND LIMITATIONS

Five validation cohorts (Prostate Cancer Research International: Active Surveillance, Johns Hopkins, Toronto, Memorial Sloan Kettering Cancer Center, and University of California San Francisco), comprising 5105 men on AS, were eligible for analysis. The individual cohorts comprised 429-2416 men, with a median follow-up between 36 and 84 mo, in both community and academic practices mainly from western countries. Abilities of the PASS-RCs to discriminate between men with and without reclassification on biopsy were reasonably good (area under the receiver operating characteristic curve values 0.68 and 0.65). The PASS-RCs were moderately well calibrated, and had a greater net benefit than most default strategies between a predicted 10% and 30% risk of reclassification.

CONCLUSIONS

Both PASS-RCs improved the balance between detecting reclassification and performing surveillance biopsies by reducing unnecessary biopsies. Recalibration to the local setting will increase their clinical usefulness and is therefore required before implementation.

PATIENT SUMMARY

Unnecessary prostate biopsies while on active surveillance (AS) should be avoided as much as possible. The ability of two calculators to selectively identify men at risk of progression was tested in a large cohort of men with low-risk prostate cancer on AS. The calculators were able to prevent unnecessary biopsies in some men. Usefulness of the calculators can be increased by adjusting them to the characteristics of the population of the clinic in which the calculators will be used.

A novel predictor of clinical progression in patients on active surveillance for prostate cancer

INTRODUCTION

Active surveillance (AS) is standard of care in low-risk prostate cancer (PCa). This study describes a novel total cancer location (TCLo) density metric and aims to determine its performance in predicting clinical progression (CP) and grade progression (GP).

METHODS

This was a retrospective study of patients on AS after confirmatory biopsy (CBx). We excluded patients with Gleason ≥7 at CBx and <2 years followup. TCLo was the number of locations with positive cores at diagnosis (DBx) and CBx. TCLo density was TCLo/prostate volume (PV). CP was progression to any active treatment while GP occurred if Gleason ≥7 was identified on repeat biopsy or surgical pathology. Independent predictors of time to CP or GP were estimated with Cox regression. Kaplan-Meier analysis compared progression-free survival (PFS) curves between TCLo density groups. Test characteristics of TCLo density were explored with receiver operating characteristic (ROC) curves.

RESULTS

We included 181 patients who had CBx from 2012-2015 and met inclusion criteria. The mean age of patients was 62.58 years (standard deviation [SD] 7.13) and median followup was 60.9 months (interquartile range [IQR] 23.4). A high TCLo density score (>0.05) was independently associated with time to CP (hazard ratio [HR] 4.70; 95% confidence interval [CI] 2.62-8.42; p<0.001) and GP (HR 3.85; 95% CI 1.91-7.73; p<0.001). ROC curves showed TCLo density has greater area under the curve than number of positive cores at CBx in predicting progression.

CONCLUSIONS

TCLo density is able to stratify patients on AS for risk of CP and GP. With further validation, it could be added to the decision-making algorithm in AS for low-risk localized PCa.

Active surveillance for prostate and thyroid cancers: evolution in clinical paradigms and lessons learned

The adverse effects of overdiagnosis and overtreatment observed in men with clinically insignificant prostate cancers after the introduction of prostate-specific antigen-based screening are now being observed in those with thyroid cancer, owing to the introduction of new imaging technologies. Thus, the evolving paradigm of active surveillance in prostate and thyroid cancers might be valuable in informing the development of future active surveillance protocols. The lessons learned from active surveillance and their implications include the need to minimize the use of broad, population-based screening programmes that do not incorporate patient education and the need for individualized or shared decision-making, which can decrease the extent of overtreatment. Furthermore, from the experience in patients with prostate cancer, we have learned that consensus is required regarding the optimal selection of patients for active surveillance, using more-specific evidence-based methods for stratifying patients by risk. In this Review, we describe the epidemiology, pathology and screening guidelines for the management of patients with prostate and thyroid cancers; the evidence of overdiagnosis and overtreatment; and provide overviews of existing international active surveillance protocols.

Defining clinically significant prostate cancer on the basis of pathological findings

The definition of clinically significant prostate cancer is a dynamic process that was initiated many decades ago, when there was already evidence that a great proportion of patients with prostate cancer diagnosed at autopsy never had any clinical symptoms. Autopsy studies led to examinations of radical prostatectomy (RP) specimens and the establishment of the definition of significant cancer at RP: tumour volume of 0.5 cm³ , Gleason grade 6 [Grade Group (GrG) 1], and organ-confined disease. RP studies were then used to develop prediction models for significant cancer by the use of needle biopsies. The first such model was used to delineate the first active surveillance (AS) criteria, known as the 'Epstein' criteria, in which patients with a cancer Gleason score of 3 + 3 = 6 (GrG1) involving fewer than two cores, and <50% of any given core, and a prostate-specific antigen density of <0.15 ng/ml per cm³ had a minimal risk of significant cancer at RP. These were adopted as components of the 'very-low-risk category' of the National Comprehensive Cancer Network guidelines, in which AS is supported as a management option. With the increase in the popularity of AS, much research has been carried out to better define significant/insignificant cancer, in order to be able to safely offer AS to a larger proportion of patients without the risk of undertreatment. Research has focused on allowing higher volume tumours, focal extraprostatic extension, and a limited amount of Gleason pattern 4, and the significance of different morphological patterns of Gleason 4. Other areas of research that will probably impact on the field but that are not covered in this review include the molecular classification of tumours and imaging techniques.

Pathological Characteristics of Prostate Cancer in Men Aged < 50 Years Treated with Radical Prostatectomy: a Multi-Centre Study in Korea

BACKGROUND

Recently, younger prostate cancer (PCa) patients have been reported to harbour more favourable disease characteristics after radical prostatectomy (RP) than older men. We analysed young men (<50 years) with PCa among the Korean population, paying attention to pathological characteristics on RP specimen and biochemical recurrence (BCR).

METHODS

The multi-centre, Severance Urological Oncology Group registry was utilized to identify 622 patients with clinically localized or locally advanced PCa, who were treated with RP between 2001 and 2017. Patients were dichotomized into two groups according to age (< 50-year-old [n = 75] and ≥ 50-year-old [n = 547]), and clinicopathological characteristics were analysed. Propensity score matching was used when assessing BCR between the two groups.

RESULTS

Although biopsy Gleason score (GS) was lower in younger patients (P = 0.033), distribution of pathologic GS was similar between the two groups (13.3% vs. 13.9% for GS ≥ 8, P = 0.191). There was no significant difference in pathologic T stage between the < 50- and ≥ 50-year-old groups (69.3% vs. 68.0% in T2 and 30.7% vs. 32.0% in ≥ T3, P = 0.203). The positive surgical margin rates were similar between the two groups (20.0% vs. 27.6%, P = 0.178). BCR-free survival rates were also similar (P = 0.644) between the two groups, after propensity matching.

CONCLUSION

Contrary to prior reports, younger PCa patients did not have more favourable pathologic features on RP specimen and showed similar BCR rates compared to older men. These findings should be considered when making treatment decisions for young Korean patients with PCa.

Evidence-based approach to active surveillance of prostate cancer

Active surveillance is a good management option for some men with non-metastatic prostate cancer. In this review, we examine the evidence for several topics related to active surveillance. We examine: (1) which patients should be eligible for active surveillance, (2) what follow-up (monitoring) protocols should be used for men on surveillance, (3) what is the role of prostate magnetic resonance imaging (MRI) for men on surveillance, and (4) what is the prognosis for men who choose surveillance compared to radical treatment. In many instances, the evidence is evolving or lacking. In these situations, we highlight the limitations of the data.

Green tea extract for prevention of prostate cancer progression in patients on active surveillance

Background

Active surveillance (AS) has evolved as a management strategy for men with low grade prostate cancer (PCa). However, these patients report anxiety, doubts about the possible progression of the disease as well as higher decisional conflict regarding selection of active surveillance, and have been reported to ultimately opt for treatment without any major change in tumor characteristics. Currently, there is a paucity of research that systematically examines alternate strategies for this target population.

Methods

We conducted a review the evidence from epidemiological, in vitro, preclinical and early phase trials that have evaluated green tea catechins (GTC) for secondary chemoprevention of prostate cancer, focused on men opting for active surveillanceof low grade PCa.

Results

Results of our review of the in vitro, preclinical and phase I-II trials, demonstrates that green tea catechins (GTC) can modulate several relevant intermediate biological intermediate endpoint biomarkers implicated in prostate carcinogenesis as well as clinical progression of PCa, without major side effects.

Discussion

Although clinical trials using GTC have been evaluated in early phase trials in men diagnosed with High-Grade Prostatic Intraepithelial Neoplasia, Atypical Small Acinar Proliferation and in men with localized disease before prostatectomy, the effect of GTC on biological and clinical biomarkers implicated in prostate cancer progression have not been evaluated in this patient population.

Conclusion

Results of these studies promise to provide a strategy for secondary chemoprevention, reduce morbidities due to overtreatment and improve quality of life in men diagnosed with low-grade PCa.

Development and validation of a novel risk score for the detection of insignificant prostate cancer in unscreened patient cohorts

Background

Active surveillance is recommended for insignificant prostate cancer (PCa). Tools exist to identify suitable candidates using clinical variables. We aimed to develop and validate a novel risk score (NRS) predicting which patients are harbouring insignificant PCa.

Methods

We used prospectively collected data from 8040 consecutive unscreened patients who underwent radical prostatectomy between 2006 and 2016. Of these, data from 2799 patients with Gleason 3 + 3 on biopsy were used to develop a multivariate model predicting the presence of insignificant PC at radical prostatectomy (ERSPC updated definition³: Gleason 3 + 3 only, index tumour volume < 1.3 cm³ and total tumour volume < 2.5 cm³). This was used to develop a novel risk score (NRS) which was validated in an equivalent independent cohort (n = 441). We compared the accuracy of existing predictive tools and the NRS in these cohorts.

Results

The NRS (incorporating PSA, prostate volume, age, clinical T Stage, percent and number of positive biopsy cores) outperformed pre-existing predictive tools in derivation and validation cohorts (AUC 0.755 and 0.76, respectively). Selection bias due to analysis of a surgical cohort is acknowledged.

Conclusions

The advantage of the NRS is that it can be tailored to patient characteristics and may prove to be valuable tool in clinical decision-making.

Active surveillance review: contemporary selection criteria, follow-up, compliance and outcomes

The primary goal of active surveillance (AS) is to prevent overtreatment by selecting patients with low-risk prostate cancer (PCa) and closely monitoring them so that definitive treatment can be offered when needed. With the increasing popularity of AS as a management strategy for men with localized PCa, it is important to understand all the contemporary guidelines and criteria that exist for AS and the differences among them. No single optimal management strategy for clinically localized, early-stage disease has been universally accepted. The implementation of AS varies widely between institutions, from inclusion criteria to follow-up protocols, with the most notable differences seen in maximum accepted Gleason score, T-stage and prostate-specific antigen (PSA) parameters. The objectives of this review were to systematically summarize the current literature on AS strategy, present an overview of the various published guidelines and criteria that are used for AS at several major institutions as well as discuss goals and trade-offs of the various criteria. A comprehensive search of the PubMed and Embase databases from 1990 to 2017 was performed to identify studies pertaining to AS criteria and trends. Trends in AS uptake and use in Canada, USA and Europe were reviewed to demonstrate the current trends and outcomes of AS to offer greater insight into the differences, nature and efficacy of various AS protocols. AS is a compelling antidote to the current PCa overtreatment phenomena; however, when considering patients for AS it is important to understand the differences between protocols, and review published results to appreciate the impact on follow-up.

Prostate Biopsy in Active Surveillance Protocols: Immediate Re-biopsy and Timing of Subsequent Biopsies

PURPOSE OF REVIEW

This manuscript reviews contemporary literature regarding prostate cancer active surveillance (AS) protocols as well as other tools that may guide the management of biopsy frequency and assess the possibility of progression in low-risk prostate cancer.

RECENT FINDINGS

There is no consensus regarding the timing of surveillance biopsies; however, an immediate repeat biopsy within 12 months of diagnosis for patients considering AS confirms patients who have favorable risk disease yet also identifies patients who were undersampled initially. Studies regarding multiparametric MRI, nomograms, and biomarkers show promise in risk stratifying and counseling patients during AS. Further studies are needed to determine if these supplemental tests can decrease the frequency of surveillance biopsies. An immediate re-biopsy can help to reduce the risk of missing clinically significant disease. Other clinical tools, including mpMRI, exist that can be used as an adjunct to counsel patients and guide a personalized discussion regarding the frequency of surveillance biopsies.

Active surveillance for prostate cancer: a systematic review of contemporary worldwide practices

In the last decade, active surveillance (AS) has emerged as an acceptable choice for low-risk prostate cancer (PC), however there is discordance amongst large AS cohort studies with respect to entry and monitoring protocols. We systematically reviewed worldwide AS practices in studies reporting ≥5 years follow-up. We searched PubMed and Medline 2000-now and identified 13 AS cohorts. Three key areas were identified: (I) patient selection; (II) monitoring protocols; (III) triggers for intervention—(I) all studies defined clinically localised PC diagnosis as T2b disease or less and most agreed on prostate-specific antigen (PSA) threshold (<10 µg/L) and Gleason score threshold (3+3). Inconsistency was most notable regarding pathologic factors (e.g., number of positive cores); (II) all agreed on PSA surveillance as crucial for monitoring, and most agreed that confirmatory biopsy was required within 12 months of initiation. No consensus was reached on optimal timing of digital rectal examination (DRE), general health assessment or re-biopsy strategies thereafter; (III) there was no universal agreement for intervention triggers, although Gleason score, number or percentage of positive cancer cores, maximum cancer length (MCL) and PSA doubling time were used by several studies. Some also used imaging or re-biopsy. Despite consistent high progression-free/cancer-free survival and conversion-to-treatment rates, heterogeneity exists amongst these large AS cohorts. Combining existing evidence and gathering more long-term evidence [e.g., the Movember’s Global AS database or additional information on use of magnetic resonance imaging (MRI)] is needed to derive a broadly supported guideline to reduce variation in clinical practice.

The management of active surveillance in prostate cancer: validation of the Canary Prostate Active Surveillance Study risk calculator with the Spanish Urological Association Registry

The follow up of patients on active surveillance requires to repeat prostate biopsies. Predictive models that identify patients at low risk of progression or reclassification are essential to reduce the number of unnecessary biopsies. The aim of this study is to validate the Prostate Active Surveillance Study risk calculator (PASS-RC) in the multicentric Spanish Urological Association Registry of patients on active surveillance (AS), from common clinical practice.

Preventing clinical progression and need for treatment in patients on active surveillance for prostate cancer

PURPOSE OF REVIEW

Active surveillance is an established treatment option for men with localized, low-risk prostate cancer (CaP). It entails the postponement of immediate therapy with the option of delayed intervention upon disease progression. The rate of clinical progression and need for treatment on active surveillance is approximately 50% over 15 years. The present review summarizes recent data on current methods, attempting to prevent clinical progression.

RECENT FINDINGS

Patient selection for active surveillance is the first mandatory step required to lower progression. Adherence to active surveillance protocols is critical in making sure patients are monitored well and treated early when progression occurs. Before active surveillance allocation and during active surveillance follow-up, methods involving multiparametric MRI, prostate specific antigen derivatives, biopsy factors, urinary, tissue and genetic markers can be used to prevent clinical progression and/or identify those at risk for progression. Medications such as 5α-reductase inhibitors and others might inhibit disease progression in patients on active surveillance.

SUMMARY

Active surveillance is required because of overdiagnosis, along with our inability to accurately predict individual CaP behavior. Several methods can potentially reduce the risk of CaP progression in patients with active surveillance. However, a measure of uncertainty and fear of progression will always accompany patients with active surveillance and the physicians treating them.

Communicating risk in active surveillance of localised prostate cancer: a protocol for a qualitative study

INTRODUCTION

One in five men is likely to receive a diagnosis of prostate cancer (PCa) by the age of 85 years. Men diagnosed with low-risk PCa may be eligible for active surveillance (AS) to monitor their cancer to ensure that any changes are discovered and responded to in a timely way. Communication of risk in this context is more complicated than determining a numerical probability of risk, as patients wish to understand the implications of risk on their lives in concrete terms. Our study will examine how risk for PCa is perceived, experienced and communicated by patients using AS with their health professionals, and the implications for treatment and care.

METHODS AND ANALYSIS

This is a proof of concept study, testing out a multimethod, qualitative approach to data collection in the context of PCa for the first time in Australia. It is being conducted from November 2016 to December 2017 in an Australian university hospital urology clinic. Participants are 10 men with a diagnosis of localised PCa, who are using an AS protocol, and 5 health professionals who work with this patient group (eg, urologists and Pca nurses). Data will be collected using observations of patient consultations with health professionals, patient questionnaires and interviews, and interviews with healthcare professionals. Analysis will be conducted in two stages. First, observational data from consultations will be analysed thematically to encapsulate various dimensions of risk classification and consultation dialogue. Second, interview data will be coded to derive meaning in text and analysed thematically. Overarching themes will represent patient and health professional perspectives of risk communication.

ETHICS AND DISSEMINATION

Ethical approval for the study has been granted by Macquarie University Human Research Ethics Committee, approval 5201600638. Knowledge translation will be achieved through publications, reports and conference presentations to patients, families, clinicians and researchers.

Predicting clinically significant prostate cancer based on pre-operative patient profile and serum biomarkers

Previous studies have reported association of multiple preoperative factors predicting clinically significant prostate cancer with varying results. We assessed the predictive model using a combination of hormone profile, serum biomarkers, and patient characteristics in order to improve the accuracy of risk stratification of patients with prostate cancer. Data on 224 patients from our prostatectomy database were queried. Demographic characteristics, including age, body mass index (BMI), clinical stage, clinical Gleason score (GS) as well as serum biomarkers, such as prostate-specific antigen (PSA), parathyroid hormone (PTH), calcium (Ca), prostate acid phosphatase (PAP), testosterone, and chromogranin A (CgA), were used to build a predictive model of clinically significant prostate cancer using logistic regression methods. We assessed the utility and validity of prediction models using multiple 10-fold cross-validation. Bias-corrected area under the receiver operating characteristics (ROC) curve (bAUC) over 200 runs was reported as the predictive performance of the models. On univariate analyses, covariates most predictive of clinically significant prostate cancer were clinical GS (OR 5.8, 95% CI 3.1–10.8; P < 0.0001; bAUC = 0.635), total PSA (OR 1.1, 95% CI 1.06–1.2; P = 0.0003; bAUC = 0.656), PAP (OR 1.5, 95% CI 1.1–2.1; P = 0.016; bAUC = 0.583), and BMI (OR 1.064, 95% C.I. 0.998, 1.134; P < 0.056; bAUC = 0.575). On multivariate analyses, the most predictive model included the combination of preoperative PSA, prostate weight, clinical GS, BMI and PAP with bAUC 0.771 ([2.5, 97.5] percentiles = [0.76, 0.78]). Our model using preoperative PSA, clinical GS, BMI, PAP, and prostate weight may be a tool to identify individuals with adverse oncologic characteristics and classify patients according to their risk profiles.

Reclassification Rates of Patients Eligible for Active Surveillance After the Addition of Magnetic Resonance Imaging-Ultrasound Fusion Biopsy: An Analysis of 7 Widely Used Eligibility Criteria

OBJECTIVES

To evaluate the impact of adding magnetic resonance imaging-ultrasound (MRI-US) fusion biopsy cores to standard 12-core biopsy in selecting men for active surveillance (AS).

MATERIALS AND METHODS

Among men undergoing a fusion biopsy for evaluation of prostate cancer, we selected men who were eligible for at least 1 of 7 different AS criteria based on the standard biopsy alone. We assessed each patient's eligibility for each AS criterion with and without the inclusion of fusion biopsy cores. The primary end point was the proportion of men who were initially eligible for AS but became ineligible after addition of the fusion biopsy cores.

RESULTS

A total of 100 men were eligible for at least 1 AS criterion. After addition of fusion biopsy cores, the proportion of men who became ineligible for AS varied from 10.3% to 40.7%. Criteria that incorporated an absolute maximum number of cores positive had the highest rates of ineligibility. Using a percentage of cores positive helped to reduce the number of patients who would have been excluded. Combining the targeted biopsy cores into one, or taking the single core with the highest grade or volume did not appear to reduce the proportion of men who became ineligible.

CONCLUSIONS

The addition of fusion biopsy to standard 12-core biopsy significantly increased the number of men who became ineligible for AS. Using the percent of cores positive, instead of an absolute number, allowed fewer exclusions. AS criteria may need to be updated to prevent the unnecessary exclusion of men due to an oversampling of low-risk disease.

The performance of PI-RADSv2 and quantitative apparent diffusion coefficient for predicting confirmatory prostate biopsy findings in patients considered for active surveillance of prostate cancer

PURPOSE

To assess the performance of the updated Prostate Imaging Reporting and Data System (PI-RADSv2) and the apparent diffusion coefficient (ADC) for predicting confirmatory biopsy results in patients considered for active surveillance of prostate cancer (PCA).

METHODS

IRB-approved, retrospective study of 371 consecutive men with clinically low-risk PCA (initial biopsy Gleason score ≤6, prostate-specific antigen <10 ng/ml, clinical stage ≤T2a) who underwent 3T-prostate MRI before confirmatory biopsy. Two independent radiologists recorded the PI-RADSv2 scores and measured the corresponding ADC values in each patient. A composite score was generated to assess the performance of combining PI-RADSv2 + ADC.

RESULTS

PCA was upgraded on confirmatory biopsy in 107/371 (29%) patients. Inter-reader agreement was substantial (PI-RADSv2: k = 0.73; 95% CI [0.66-0.80]; ADC: r = 0.74; 95% CI [0.69-0.79]). Accuracies, sensitivities, specificities, positive predicted value and negative predicted value of PI-RADSv2 were 85, 89, 83, 68, 95 and 78, 82, 76, 58, 91% for ADC. PI-RADSv2 accuracy was significantly higher than that of ADC for predicting biopsy upgrade (p = 0.014). The combined PI-RADSv2 + ADC composite score did not perform better than PI-RADSv2 alone. Obviating biopsy in patients with PI-RADSv2 score ≤3 would have missed Gleason Score upgrade in 12/232 (5%) of patients.

CONCLUSION

PI-RADSv2 was superior to ADC measurements for predicting PCA upgrading on confirmatory biopsy.

Prognostic Significance of a Negative Confirmatory Biopsy on Reclassification Among Men on Active Surveillance

OBJECTIVE

To examine the association between absence of disease on confirmatory biopsy and risk of pathologic reclassification in men on active surveillance (AS).

MATERIALS AND METHODS

Men with grade groups 1 and 2 disease on AS between 2002 and 2015 were identified who received a confirmatory biopsy within 1 year of diagnosis and ≥3 biopsies overall. The primary outcomes were pathologic reclassification by grade (any increase in primary Gleason pattern or Gleason score) or volume (>33% of sampled cores involved or increase in the number of cores with >50% involvement). The effect of a negative confirmatory biopsy survival was evaluated using Kaplan-Meier analysis and a Cox proportional hazards modeling.

RESULTS

Out of 635 men, 224 met inclusion criteria (median follow-up: 55.8 months). A total of 111 men (49.6%) had a negative confirmatory biopsy. Decreased grade reclassification (69.7% vs 83.9%; P = .01) and volume reclassification (66.3% vs 87.4%; P = .004) was seen at 5 years for men with a negative confirmatory biopsy compared with those with a positive biopsy. On adjusted analysis, a negative confirmatory biopsy was associated with a decreased risk of grade reclassification (hazard ratio, 0.51; 95% confidence interval, 0.28-0.94; P = .03) and volume reclassification (hazard ratio, 0.32; 95% confidence interval, 0.17-0.61; P = .0006) at a median of 4.7 years.

CONCLUSION

Absence of cancer on the confirmatory biopsy is associated with a significant decrease in rate of grade and volume reclassification among men on AS. This information may be used to better counsel men on AS.

Selection Criteria for Active Surveillance of Patients with Prostate Cancer in Korea: A Multicenter Analysis of Pathology after Radical Prostatectomy

Purpose

Korean patients with prostate cancer (PC) typically present with a more aggressive disease than patients in Western populations. Consequently, it is unclear if the current criteria for active surveillance (AS) can safely be applied to Korean patients. Therefore, this study was conducted to define appropriate selection criteria for AS for patients with PC in Korea.

Materials and Methods

We conducted a multicenter retrospective study of 2,126 patients with low risk PC who actually underwent radical prostatectomy. The primary outcome was an unfavorable disease, which was defined by non-organ confined disease or an upgrading of the Gleason score to ≥ 7 (4+3). Predictive variables of an unfavorable outcome were identified by multivariate analysis using randomly selected training samples (n=1,623, 76.3%). We compared our selected criteria to various Western criteria for the primary outcome and validated our criteria using the remaining validation sample (n=503, 23.7%).

Results

A non-organ confined disease rate of 14.9% was identified, with an increase in Gleason score ≥ 7 (4+3) of 8.7% and a final unfavorable disease status of 20.8%. The following criteria were selected: Gleason score ≤ 6, clinical stage T1-T2a, prostate-specific antigen (PSA) ≤ 10 ng/mL, PSA density < 0.15 ng/mL/mL, number of positive cores ≤ 2, and maximum cancer involvement in any one core ≤ 20%. These criteria provided the lowest unfavorable disease rate (11.7%) when compared to Western criteria (13.3%-20.7%), and their validity was confirmed using the validation sample (5.9%).

Conclusion

We developed AS criteria which are appropriate for Korean patients with PC. Prospective studies using these criteria are now warranted.

The Emerging Role of MRI in Prostate Cancer Active Surveillance and Ongoing Challenges

OBJECTIVE

Active surveillance (AS) has emerged as a management strategy for preventing overtreatment of indolent prostate cancer. Selection of patients for AS has traditionally proved challenging and resulted in 20-30% misclassification rates. MRI has potential to help overcome this limitation, broaden selection criteria to increase recruitment, and minimize the invasive nature of AS follow-up.

CONCLUSION

The main issues surrounding MRI and AS are the heterogeneity of inclusion criteria, the definition of significant disease, and agreement about what constitutes radiologic progression. Prospective cohorts with MRI at enrollment and long-term follow-up are required to further address these issues.

Active surveillance as a therapeutic option for patients with low-risk prostate cancer according to the 2014 International Society of Urological Pathology grading system: a review

Extended prostate-specific antigen screening and the tightly focused execution of biopsies have resulted in an increased rate of detection, and thereby increased interventional treatment, of prostate cancer (PCa). The potential overdiagnosis and overtreatment of PCa patients have repeatedly been criticized in national and international literature. Controlled monitoring of patients in the setting of active surveillance (AS) can prevent overtreatment and the needless impairment of quality of life. The prerequisite for this treatment strategy is the diagnosis of low-grade/risk PCa. Since 2005, the modified Gleason grading system has been used for the histological assessment of PCa. In 2014, the International Society of Urological Pathology recommended a new prognostic grading system with five grades analogous to the modified Gleason score. This review discusses the importance of pathological histological analysis of PCa, particularly in the face of recent amendments, and sheds light on the significance of the new grading system for the diagnosis of low-grade/risk PCa with regard to the therapeutic option of AS.

Prostate-specific antigen patterns in US and European populations: comparison of six diverse cohorts

OBJECTIVE

To determine whether there are differences in prostate-specific antigen (PSA) levels at diagnosis or changes in PSA levels between US and European populations of men with and without prostate cancer (PCa).

SUBJECTS AND METHODS

We analysed repeated measures of PSA from six clinically and geographically diverse cohorts of men: two cohorts with PSA-detected PCa, two cohorts with clinically detected PCa and two cohorts without PCa. Using multilevel models, average PSA at diagnosis and PSA change over time were compared among study populations.

RESULTS

The annual percentage PSA change of 4-5% was similar between men without cancer and men with PSA-detected cancer. PSA at diagnosis was 1.7 ng/mL lower in a US cohort of men with PSA-detected PCa (95% confidence interval 1.3-2.0 ng/mL), compared with a UK cohort of men with PSA-detected PCa, but there was no evidence of a different rate of PSA change between these populations.

CONCLUSION

We found that PSA changes over time are similar in UK and US men diagnosed through PSA testing and even in men without PCa. Further development of PSA models to monitor men on active surveillance should be undertaken in order to take advantage of these similarities. We found no evidence that guidelines for using PSA to monitor men cannot be passed between US and European studies.

Timing of Adverse Prostate Cancer Reclassification on First Surveillance Biopsy: Results from the Canary Prostate Cancer Active Surveillance Study

PURPOSE

During active surveillance for localized prostate cancer, the timing of the first surveillance biopsy varies. We analyzed the Canary PASS (Prostate Cancer Active Surveillance Study) to determine biopsy timing influence on rates of prostate cancer adverse reclassification at the first active surveillance biopsy.

MATERIALS AND METHODS

Of 1,085 participants in PASS, 421 had fewer than 34% of cores involved with cancer and Gleason sum 6 or less, and thereafter underwent on-study active surveillance biopsy. Reclassification was defined as an increase in Gleason sum and/or 34% or more of cores with prostate cancer. First active surveillance biopsy reclassification rates were categorized as less than 8, 8 to 13 and greater than 13 months after diagnosis. Multivariable logistic regression determined association between reclassification and first biopsy timing.

RESULTS

Of 421 men, 89 (21.1%) experienced reclassification at the first active surveillance biopsy. Median time from prostate cancer diagnosis to first active surveillance biopsy was 11 months (IQR 7.8-13.8). Reclassification rates at less than 8, 8 to 13 and greater than 13 months were 24%, 19% and 22% (p = 0.65). On multivariable analysis, compared to men biopsied at less than 8 months the OR of reclassification at 8 to 13 and greater than 13 months were 0.88 (95% CI 0.5,1.6) and 0.95 (95% CI 0.5,1.9), respectively. Prostate specific antigen density 0.15 or greater (referent less than 0.15, OR 1.9, 95% CI 1.1, 4.1) and body mass index 35 kg/m² or greater (referent less than 25 kg/m², OR 2.4, 95% CI 1.1,5.7) were associated with increased odds of reclassification.

CONCLUSIONS

Timing of the first active surveillance biopsy was not associated with increased adverse reclassification but prostate specific antigen density and body mass index were. In low risk patients on active surveillance, it may be reasonable to perform the first active surveillance biopsy at a later time, reducing the overall cost and morbidity of active surveillance.

Can testosterone therapy be offered to men on active surveillance for prostate cancer? Preliminary results

This report presents our experience with T therapy in a cohort of T-deficient men on active surveillance (AS) for Gleason 3 + 3 and Gleason 3 + 4 prostate cancer (PCa). A retrospective chart review identified 28 men with T deficiency who underwent T therapy (T group) for at least 6 months while on AS for PCa. A comparison group of 96 men on AS for PCa with untreated T deficiency (no-T group) was identified at the same institution. The AS protocol followed a modified Epstein criteria and allowed inclusion of men with a single core of low-volume Gleason 3 + 4 PCa. Mean age was 59.5 and 61.3 years, and mean follow-up was 38.9 and 42.4 months for the T and no-T groups, respectively. Of all 28 men in the T group, 3 (10.7%) men developed an increase in Gleason score while on AS. Of 22 men in the T group with Gleason 3 + 3 disease, 7 (31.8%) men developed biopsy progression including 3 men (13.6%) who developed Gleason 3 + 4 PCa. Of 6 men with Gleason 3 + 4 disease at baseline, 2 (33.3%) men developed an increase in tumor volume, and none developed upgrading beyond Gleason 3 + 4. All 96 men in the no-T group had Gleason 3 + 3 disease at baseline and, 43 (44.7%) developed biopsy progression, including 9 men (9.38%) with upgrading to Gleason 7 (3 + 4). Biopsy progression rates were similar for both groups and historical controls. Biopsy progression in men on AS appears unaffected by T therapy over 3 years. Prospective placebo-controlled trials of T therapy in T-deficient men on AS should be considered given the symptomatic benefits experienced by treated men.

Active surveillance: a cautionary tale

Objective

To determine if the practice of active surveillance for prostate cancer (PCa) at the District General Hospital (DGH) level produces outcomes in keeping with those published from clinical trials.

Subjects

A cohort of 47 patients started on active surveillance for prostate cancer in 2002–2003.

Methods

Retrospective review of case notes, electronic records and the regional cancer register.

Results

This cohort of patients had significantly higher disease-specific mortality and greater progression to palliative forms of management compared to previously published studies.

Conclusion

The implementation of AS in routine clinical practice may be inconsistent, potentially leading to compromised patient outcomes.

Sociodemographic and Clinical Predictors of Switching to Active Treatment among a Large, Ethnically Diverse Cohort of Men with Low Risk Prostate Cancer on Observational Management

PURPOSE

We determined the clinical and sociodemographic predictors of beginning active treatment in an ethnically diverse population of men with low risk prostate cancer initially on observational treatment.

MATERIALS AND METHODS

We retrospectively studied men diagnosed with low risk prostate cancer between 2004 and 2012 at Kaiser Permanente Northern California who did not receive any treatment within the first year of diagnosis and had at least 2 years of followup. We used Cox proportional hazards regression models to determine factors associated with time from diagnosis to active treatment.

RESULTS

We identified 2,228 eligible men who were initially on observation, of whom 27% began active treatment during followup at a median of 2.9 years. NonHispanic black men were marginally more likely to begin active treatment than nonHispanic white men independent of baseline and followup clinical measures (HR 1.3, 95% CI 1.0-1.7). Among men who remained on observation nonHispanic black men were rebiopsied within 24 months of diagnosis at a slightly lower rate than nonHispanic white men (HR 0.70, 95% CI 0.6-1.0). Gleason grade progression (HR 3.3, 95% CI 2.7-4.1) and PSA doubling time less than 48 months (HR 2.9, 95% CI 2.3-3.7) were associated with initiation of active treatment independent of race.

CONCLUSIONS

Sociodemographic factors such as ethnicity and education may independently influence the patient decision to pursue active treatment and serial biopsies during active surveillance. These factors are important for further studies of prostate cancer treatment decision making.