A Negative Confirmatory Biopsy Among Men on Active Surveillance for Prostate Cancer Does Not Protect Them from Histologic Grade Progression

Impact of a negative confirmatory biopsy on risk of disease progression among men on active surveillance for prostate cancer

OBJECTIVE

Most prostate cancer active surveillance (AS) protocols suggest a confirmatory biopsy within 12 to 18 months of diagnosis to mitigate the risk of unsampled high-grade disease. We investigate whether the results of confirmatory biopsy impact AS outcomes and could be used to tailor surveillance intensity.

METHODS

We retrospectively reviewed our institutional database of prostate cancer patients managed by AS from 1997 to 2019 who underwent confirmatory biopsy and ≥3 biopsies overall. Biopsy progression was defined as either an increase in grade group or an increase in the proportion of positive biopsy cores to >34% and was compared between patients with a negative vs positive confirmatory biopsy using the Kaplan-Meier method and Cox proportional hazards regression.

RESULTS

We identified 452 patients meeting inclusion criteria for this analysis, of whom 169 (37%) had a negative confirmatory biopsy. With a median follow-up of 6.8 years, 37% of patients progressed to treatment, most commonly due to biopsy progression. A negative confirmatory biopsy was significantly associated with biopsy progression-free survival in multivariable analysis (HR 0.54, 95% CI 0.34-0.88, P = 0.013), adjusting for known clinical and pathologic factors, including use of mpMRI prior to confirmatory biopsy. Negative confirmatory biopsy was also associated with an increased risk of adverse pathologic features at prostatectomy but not with biochemical recurrence among men who ultimately underwent definitive treatment.

CONCLUSIONS

A negative confirmatory biopsy is associated with a lower risk of biopsy progression. While the increased risk of adverse pathology at time of definitive treatment sounds a small cautionary note regarding decreasing surveillance intensity, the majority of such patients have a favorable outcome on AS.

Combination of MRI prostate and 18F-DCFPyl PSMA PET/CT detects all clinically significant prostate cancers in treatment-naive patients: An international multicentre retrospective study

INTRODUCTION

Clinical and biochemical assessment and biopsies can miss clinically significant prostate cancers (csPCa) in up to 20% of patients and diagnose clinically insignificant tumours leading to overtreatment. This retrospective study analyses the accuracy of ¹⁸ F-DCFPyL PET/CT in detecting csPCa as a primary diagnostic tool and directly compares it with mpMRI prostate in treatment-naive patients. The two modalities are then correlated to determine whether they are better in combination, than either alone.

METHODS

This is a retrospective dual-institution study of patients who underwent contemporaneous MRI and PSMA-PET between January 2017 and March 2020 with histologic confirmation. The images were re-reviewed and concordance between modalities assessed. Results were compared with histopathology to determine the ability of MRI and PSMA-PET to detect csPCA.

RESULTS

MRI and PSMA-PET detected the same index lesion in 90.8% of cases with a kappa of 0.82. PET detected an additional 6.2% of index lesions which were MRI occult. MRI detected an additional 3.1% which were PET occult. No additional csPCa was identified on pathology which was not seen on imaging. The sensitivity of PSMA-PET in detecting csPCa is 96.7% and that of MRI is 93.4% with no statistically significant difference between the two (P = 0.232). Both modalities detected all four cases of non-csPCa with these being considered false positives.

CONCLUSION

Both mpMRI and 18F-DCFPyL-PSMA-PET/CT have high sensitivity for detecting csPCa with high agreement between modalities. There were no synchronous csPCa lesions detected on pathology that were not detected on imaging too.

Risk of progression following a negative biopsy in prostate cancer active surveillance

BACKGROUND

Currently, follow-up protocols are applied equally to men on active surveillance (AS) for prostate cancer (PCa) regardless of findings at their initial follow-up biopsy. To determine whether less intensive follow-up is suitable following negative biopsy findings, we assessed the risk of converting to active treatment, any subsequent upgrading, volume progression (>33% positive cores), and serious upgrading (grade group >2) for negative compared with positive findings on initial follow-up biopsy.

METHODS

13,161 men from 24 centres participating in the Global Action Plan Active Surveillance Prostate Cancer [GAP3] consortium database, with baseline grade group ≤2, PSA ≤ 20 ng/mL, cT-stage 1-2, diagnosed after 1995, and ≥1 follow-up biopsy, were included in this study. Risk of converting to treatment was assessed using multivariable mixed-effects survival regression. Odds of volume progression, any upgrading and serious upgrading were assessed using mix-effects binary logistic regression for men with ≥2 surveillance biopsies.

RESULTS

27% of the cohort (n = 3590) had no evidence of PCa at their initial biopsy. Over 50% of subsequent biopsies in this group were also negative. A negative initial biopsy was associated with lower risk of conversion (adjusted hazard ratio: 0.45; 95% confidence interval [CI]: 0.42-0.49), subsequent upgrading (adjusted odds ratio [OR]: 0.52; 95%CI: 0.45-0.62) and serious upgrading (OR: 0.74; 95%CI: 0.59-92). Radiological progression was not assessed due to limited imaging data.

CONCLUSION

Despite heterogeneity in follow-up schedules, findings from this global study indicated reduced risk of converting to treatment, volume progression, any upgrading and serious upgrading among men whose initial biopsy findings were negative compared with positive. Given the low risk of progression and high likelihood of further negative biopsy findings, consideration should be given to decreasing follow-up intensity for this group to reduce unnecessary invasive biopsies.

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.

Update and optimization of active surveillance in prostate cancer in 2021

INTRODUCTION AND OBJECTIVES

Within the paradigm shift of the last decade in the management of prostate cancer (PCa), perhaps the most relevant event has been the emergence of active surveillance (AS) as a mandatory strategy in low-risk disease. We carry out a critical review of the clinical, pathological and radiological improvements that allow optimizing AS in 2021.

MATERIAL AND METHODS

Critical narrative review of the literature on improvement issues and controversial aspects of AS.

RESULTS

Adequate use of traditional criteria, optimized by enhanced biopsy and calculation of the prostate volume technique thanks to multiparametric magnetic resonance imaging (mpMRI) allow a better selection of patients for AS. This management should not be limited to patients under 60years of age, and patients with intermediate-risk PCa should be carefully selected to be included. Biopsies are still required in the follow-up, which can be personalized according to risk patterns. The pathologist must identify the cribriform or intraductal histology on biopsies in order to exclude these patients from AS, in the same way as with patients with alterations in DNA repair genes.

CONCLUSIONS

Controversial indications such as the inclusion of patients from intermediate-risk groups, or the transition to active treatment due to exclusive progression in tumor volume, should be further optimized. It is possible that the future competition of tissue biomarkers, the refinement of objective parameters of mpMRI and the validation of PSA kinetics calculators may sub-stratify risk groups.

Negative first follow-up prostate biopsy on active surveillance is associated with decreased risk of upgrading, suspicion of progression and converting to active treatment

OBJECTIVE

To determine the risk of disease progression and conversion to active treatment following a negative biopsy while on active surveillance (AS) for prostate cancer (PCa).

PATIENTS AND METHODS

Men on an AS programme at a single tertiary hospital (London, UK) between 2003 and 2018 with confirmed low-intermediate-risk PCa, Gleason Grade Group <3, clinical stage <T3 and a diagnostic prostate-specific antigen (PSA) level of <20 ng/mL. This cohort included men diagnosed by transrectal ultrasonography guided (12-14 cores) or transperineal (median 32 cores) biopsy. Multivariate Cox hazards regression analysis was undertaken to determine (i) risk of upgrading, (ii) clinical or radiological suspicion of disease progression, and (iii) transitioning to active treatment. Suspicion of disease progression was defined as any biopsy upgrading, >30% positive cores, magnetic resonance imaging (MRI) Likert score >3/T3 or PSA level of >20 ng/mL. Conversion to treatment included radical or hormonal treatment.

RESULTS

Among the 460 eligible patients, 23% had negative follow-up biopsy findings. The median follow-up was 62 months, with one to two repeat biopsies and two MRIs per patient during that period. Negative biopsy findings at first repeat biopsy were associated with decreased risk of converting to active treatment (hazard ration [HR] 0.18, 95% confidence interval [CI] 0.09-0.37; P < 0.001), suspicion of disease progression (HR 0.56, 95% CI: 0.34-0.94; P = 0.029), and upgrading (HR 0.48, 95% CI 0.23-0.99; P = 0.047). Data are limited by fewer men with multiple follow-up biopsies.

CONCLUSION

A negative biopsy finding at the first scheduled follow-up biopsy among men on AS for PCa was strongly associated with decreased risk of subsequent upgrading, clinical or radiological suspicion of disease progression, and conversion to active treatment. A less intense surveillance protocol should be considered for this cohort of patients.

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.

Impact of bilateral biopsy-detected prostate cancer on an active surveillance population

BACKGROUND

To assess factors that can predict active surveillance (AS) failure on serial transrectal ultrasound guided biopsies in patients with low-risk prostate cancer.

METHODS

We evaluated the records of 144 consecutive patients enrolled in AS between 2007 and 2014 at a single academic institution. Low risk inclusion criteria included PSA < 10 ng/ml, cT1c or cT2a, Grade Group (GG) 1, < 3 positive cores, and < 50% tumor in a single core with the majority having a PSA density of < 0.15. AS reclassification was defined as progression to GG ≥2, 3 or more cores, or core tumor volume ≥ 50%. Univariate and multivariate Cox proportional hazards regression analysis was used to determine predictors of reclassification and a match-pair analysis performed on a control group of patients choosing surgery.

RESULTS

Inclusion criteria were met by 130 men with a median follow-up of 52 months. The reclassification or AS failure rate was 38.5%, with the majority 41/50 (82%) finding GG ≥ 2 cancer. Most patients had unilateral disease on diagnostic biopsy (94.6%), but 40.7% had bilateral cancer detected during follow-up. Men with bilateral detected tumor were more likely to ultimately fail AS than patients with unilateral tumors (HR 4.089; P < 0.0001) and failed earlier with a reclassification-free survival of 32 vs 119 months respectively. In a matched-pair analysis using a population of 211 concurrent patients that chose radical prostatectomy rather than AS, 76% of patients with unilateral cancer on biopsy had bilateral cancer on final pathology.

CONCLUSIONS

The finding of bilateral prostate cancer on biopsy is associated with earlier AS reclassification. Finding bilateral disease may not represent disease progression, but rather enhanced detection of more extensive disease highlighting the importance of confirmatory biopsy.

Predicting Gleason Group Progression for Men on Prostate Cancer Active Surveillance: Role of a Negative Confirmatory Magnetic Resonance Imaging-Ultrasound Fusion Biopsy

PURPOSE

Active surveillance has gained acceptance as an alternative to definitive therapy in many men with prostate cancer. Confirmatory biopsies to assess the appropriateness of active surveillance are routinely performed and negative biopsies are regarded as a favorable prognostic indicator. We sought to determine the prognostic implications of negative multiparametric magnetic resonance imaging-transrectal ultrasound guided fusion biopsy consisting of extended sextant, systematic biopsy plus multiparametric magnetic resonance imaging guided targeted biopsy of suspicious lesions on magnetic resonance imaging.

MATERIALS AND METHODS

All patients referred with Gleason Grade Group 1 or 2 prostate cancer based on systematic biopsy performed elsewhere underwent confirmatory fusion biopsy. Patients who continued on active surveillance after a positive or a negative fusion biopsy were followed. The baseline characteristics of the biopsy negative and positive cases were compared. Cox regression analysis was used to determine the prognostic significance of a negative fusion biopsy. Kaplan-Meier survival curves were used to estimate Grade Group progression with time.

RESULTS

Of the 542 patients referred with Grade Group 1 (466) or Grade Group 2 (76) cancer 111 (20.5%) had a negative fusion biopsy. A total of 60 vs 122 patients with a negative vs a positive fusion biopsy were followed on active surveillance with a median time to Grade Group progression of 74.3 and 44.6 months, respectively (p <0.01). Negative fusion biopsy was associated with a reduced risk of Grade Group progression (HR 0.41, 95% CI 0.22-0.77, p <0.01).

CONCLUSIONS

A negative confirmatory fusion biopsy confers a favorable prognosis for Grade Group progression. These results can be used when counseling patients about the risk of progression and for planning future followup and biopsies in patients on active surveillance.

Younger Men With Prostate Cancer Have Lower Risk of Upgrading While on Active Surveillance: A Meta-analysis and Systematic Review of the Literature

Active surveillance has become a popular option for patients with low risk prostate cancer. Our objective was to examine the correlation between age and the risk of Gleason upgrading and biopsy progression. A systematic search was conducted. Eight studies met our eligibility criteria including 6522 patients with a median age of 65.8 (41-86) years. Per decade decrease in age, the pooled odds ratio and hazard ratio (CI 95%) for Gleason upgrading were 0.83 (0.73-0.94) and 0.87 (0.82-0.92), and for biopsy progression were 0.80 (0.74-0.86) and 0.88 (0.79-0.99), respectively. Overall, younger patients have a lower risk of GS upgrading and biopsy progression.

Radical Prostatectomy Findings in White Hispanic/Latino Men With NCCN Very Low-risk Prostate Cancer Detected by Template Biopsy

Radical prostatectomy (RP) outcomes have been studied in White and Black non-Hispanic men qualifying for Epstein active surveillance criteria (EASC). Herein, we first analyzed such outcomes in White Hispanic men. We studied 70 men with nonpalpable Gleason score 3+3=6 (Grade Group [GG] 1) prostate cancer (PCa) with ≤2 positive cores on biopsy who underwent RP. In 18 men, prostate-specific antigen (PSA) density (PSAD) was >0.15 ng/mL/g. Three of these had insignificant and 15 had significant PCa. The remaining 52 men qualified for EASC. One patient had no PCa identified at RP. Nineteen (37%) had significant PCa defined by volume (n=7), grade (n=7), and volume and grade (n=5). Nine cases were 3+4=7 (GG 2) (5/9 [56%] with pattern 4 <5%), 2 were 3+5=8 (GG 4), and 1 was 4+5=9 (GG 5). Patients with significant PCa more commonly had anterior dominant disease (11/19, 58%) versus patients with insignificant cancer (7/33, 21%) (P=0.01). In 12 cases with higher grade at RP, the dominant tumor nodule was anterior in 6 (50%) and posterior in 6 (median volumes: 1.1 vs. 0.17 cm, respectively; P=0.01). PSA correlated poorly with tumor volume (r=0.28, P=0.049). Gland weight significantly correlated with PSA (r=0.54, P<0.001). While PSAD and PSA mass density correlated with tumor volume, only PSA mass density distinguished cases with significant disease (median, 0.008 vs. 0.012 μg/g; P=0.03). In summary, a PSAD threshold of 0.15 works well in predicting significant tumor volume in Hispanic men. EASC appear to perform better in White Hispanic men than previously reported outcomes for Black non-Hispanic and worse than in White non-Hispanic men. Significant disease is often Gleason score 3+3=6 (GG 1) PCa >0.5 cm. Significant PCa is either a larger-volume anterior disease that may be detected by multiparametric magnetic resonance imaging-targeted biopsy or anterior sampling of the prostate or higher-grade smaller-volume posterior disease that in most cases should not pose immediate harm and may be detected by repeat template biopsies.

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.

[Is there still a role for active surveillance in prostate cancer?]

Long-term data demonstrate a higher oncological risk associated with active surveillance (AS) than initially anticipated. In particular, patients with more than two tumor-involved biopsy cores and/or Gleason-7a foci must be regarded as having an increased risk of developing an incurable stage of disease after an initial attempt of AS. For patients with Gleason-7a foci, the 15-year risk of suffering from an incurable tumor stage is reported as high as 60%. Furthermore, life expectancy must be regarded as one of the major risk factors to finally develop symptomatic incurable disease. A discussion has therefore started as to whether a high life expectancy should be regarded as an exclusion criterion against AS. An estimated life expectancy exceeding 15 or 20 years has been proposed for patients suffering from Gleason 7a or 6 foci at initial biopsy, respectively. Furthermore, it must be expected that a number of molecular risk factors will gain importance in the near future for the decision-making process for or against AS.

Active Surveillance in Younger Men With Prostate Cancer

Purpose The suitability of younger patients with prostate cancer (PCa) for initial active surveillance (AS) has been questioned on the basis of eventual treatment necessity and concerns of safety; however, the role of age on surveillance outcomes has not been well defined. Patients and Methods We identified men managed with AS at our institution with a minimum follow-up of 6 months. The primary study objective was to examine the association of age with risk of biopsy-based Gleason score upgrade during AS. We also examined the association of age with related end points, including overall biopsy-determined progression, definitive treatment, and pathologic and biochemical outcomes after delayed radical prostatectomy (RP), using descriptive statistics, the Kaplan-Meier method, and multivariable Cox proportional hazards regression. Results A total of 1,433 patients were followed for a median of 49 months; 74% underwent initial biopsy at a referring institution. Median age at diagnosis was 63 years, including 599 patients (42%) ≤ 60 years old and 834 (58%) > 60 years old. The 3- and 5-year biopsy-based Gleason score upgrade-free rates were 73% and 55%, respectively, for men ≤ 60 years old compared with 64% and 48%, respectively, for men older than 60 years ( P < .01). On Cox regression analysis, younger age was independently associated with lower risk of biopsy-based Gleason score upgrade (hazard ratio per 1-year decrease, 0.969 [95% CI, 0.956 to 0.983]; P < .01), and persisted upon restriction to men meeting strict AS inclusion criteria. There was no significant association between younger age and risk of definitive treatment or risk of biochemical recurrence after delayed RP. Conclusion Younger patient age was associated with decreased risk of biopsy-based Gleason score upgrade during AS but not with risk of definitive treatment in the intermediate term. AS represents a strategy to mitigate overtreatment in young patients with low-risk PCa in the early term.

What is the best way not to treat prostate cancer?

INTRODUCTION

Selective treatment approaches for prostate cancer (PCa) are warranted given the highly varied nature of the disease and the consequences associated with definitive therapy.

MATERIALS AND METHODS

We present a stepwise overview of strategies optimized to not treat PCa, ranging from improved screening practices that seek to maximize the yield at initial diagnosis, as well as refinements to clinical risk prediction and the performance of active surveillance.

RESULTS

Improved adherence to screening guidelines offering simplistic, rational practice recommendations are poised to improve the performance of early detection strategies. In addition, measures to improve the quality of PCa screening would include greater integration of novel markers with higher specificity for clinically significant disease, in an effort to stem the tide of over-diagnosis and consequential overtreatment of low-grade tumors. For men diagnosed with PCa, the use of validated, multi-variable risk stratification stands to offer greater certainty in initial management choices: consideration of active surveillance for those with low-risk status, and definitive therapy for men with intermediate and high-risk features. We review the efficacy and nature of active surveillance protocols, and offer a context for refinements that may be anticipated with future study.

CONCLUSIONS

The question of how best to not treat prostate cancer is often more complex than policies of universal treatment, yet is integral to minimize morbidity of over-treatment in patients with low-risk tumors. An array of refined risk stratification instruments, biomarkers, and genomic assays seek to improve the confidence both prior to, and following diagnosis.

Outcomes of Active Surveillance after Initial Surveillance Prostate Biopsy

PURPOSE

We analyzed the rates of disease reclassification at initial and subsequent surveillance prostate biopsy as well as the treatment outcomes of deferred therapy among men on active surveillance for prostate cancer.

MATERIALS AND METHODS

From a prospective database we identified 300 men on active surveillance who had undergone initial surveillance prostate biopsy, with or without confirmatory biopsy, within 1 year of diagnosis. Of these men 261 (87%) were classified as having NCCN very low or low risk disease at diagnosis. Disease reclassification on active surveillance was defined as the presence of 50% or more positive cores and/or surveillance prostate biopsy Gleason score upgrading. Patients with type I disease reclassification included those with any surveillance prostate biopsy Gleason score upgrading, while patients with type II reclassification had to have primary Gleason pattern 4-5 disease on surveillance prostate biopsy. Outcomes after initial surveillance prostate biopsy were evaluated using actuarial analyses.

RESULTS

At the time of initial surveillance prostate biopsy 49 (16%) and 19 (6%) patients had type I and type II disease reclassification, respectively. Those who underwent confirmatory biopsy had significantly reduced rates of type I (9% vs 23%, p=0.001) and type II (3% vs 9%, p=0.01) reclassification at initial surveillance prostate biopsy. For the 251 patients without disease reclassification at initial surveillance prostate biopsy the 2-year rates of subsequent type I and II reclassification were 17% (95% CI 0-24) and 3% (95% CI 0.1-7), respectively. For the 93 patients who received deferred therapy the 5-year biochemical progression-free probability was 89% (95% CI 79-98), including 95%, 82% and 70% among those without, and those with type I and type II disease reclassification, respectively.

CONCLUSIONS

Patients on active surveillance with stable disease at the time of initial surveillance prostate biopsy may be appropriate candidates for less intensive surveillance prostate biopsy schedules.

Significant impact of transperineal template biopsy of the prostate at a single tertiary institution

Objective:

The objective was to review the impact of transperineal biopsy (TPB) at our institution by assessing rates of cancer detection/grading, treatment outcomes and complications.

Patients and Methods:

A retrospective review of TPBs between 2009 and 2013 was performed. Variables included reason for TPB, age, prostate-specific antigen, previous histology, TPB histology, and management outcomes.

Results:

In total, 110 patients underwent 111 TPBs at our institution. On average, 22 cores were taken from each procedure. Disease-upgrade occurred in 37.5% of active surveillance patients, 35% of patients with previous negative transrectal ultrasound, and 58.8% in patients undergoing TPB for other reasons. Of these patients, anterior and/or transition zones were involved in 66%, 79%, and 80%, respectively. Involvement in anterior and/or transition zones only occurred in 40%, 37%, and 10%, respectively. About 77% of patients with disease-upgrading underwent treatment with curative intent. Complications included a 6.3% rate of acute urinary retention and 2.7% of clot retention, with no episodes of urosepsis.

Conclusions:

Transperineal biopsy at our institution showed a high rate of disease-upgrading, with a large proportion involving anterior and transition zones. A significant amount of patients went on to receive curative treatment. TPB is a valuable diagnostic procedure with minimal risk of developing urosepsis. We believe TBP should be offered as an option for all repeat prostate biopsies and considered as an option for initial prostate biopsy.

Age is Associated with Upgrading at Confirmatory Biopsy among Men with Prostate Cancer Treated with Active Surveillance

PURPOSE

Active surveillance is increasingly recommended for older men with low risk prostate cancer. Although older men have higher all cause mortality, they also have higher prostate cancer specific mortality. We hypothesized that older age is associated with an increased risk of Gleason score upgrading at confirmatory biopsy when controlling for prostate volume.

MATERIALS AND METHODS

We retrospectively reviewed data on 1,130 patients with prostate cancer who were treated with active surveillance from 1991 through 2011. We included 646 patients with clinical Gleason 6 or less, stage T2a or less prostate cancer, a confirmatory biopsy within 2 years of diagnostic biopsy and prostate magnetic resonance imaging before confirmatory biopsy. The primary outcome was Gleason score upgrading to 7 or greater on confirmatory biopsy. We used logistic regression to estimate the effect of age on upgrading, adjusting for magnetic resonance imaging prostate volume and other potential confounders.

RESULTS

Median age was 66 years (IQR 61-72) and median magnetic resonance imaging prostate volume was 41 ml (IQR 29-55). At confirmatory biopsy disease was upgraded in 55 of 646 patients (9%) and unchanged in 290 (45%) and biopsy was negative in 297 (46%). Older age was associated with higher odds of upgrading (adjusted OR 1.05, 95% CI 1.01-1.09, p=0.009). Larger prostate volume was associated with lower odds of upgrading (adjusted OR 0.80/10 ml increase, 95% CI 0.7-0.9, p=0.012).

CONCLUSIONS

Our findings suggest that older age is associated with an increased risk of misclassification on diagnostic biopsy. Older men who are interested in active surveillance should be counseled about the risks and benefits of confirmatory biopsy.

A novel technique using three-dimensionally documented biopsy mapping allows precise re-visiting of prostate cancer foci with serial surveillance of cell cycle progression gene panel

BACKGROUND

Conventional systematic biopsy has the shortcoming of sampling error and reveals "no evidence of cancer" with a rate of >50% on active surveillance (AS). The objective of this study is to report our initial experience of applying a 3D-documented biopsy-mapping technology to precisely re-visit geographically documented low-risk prostate cancer and to perform serial analysis of cell-cycle-progression (CCP) gene-panel.

METHODS

Over a period of 40 months (1/2010-4/2013), the 3D-biopsy-mapping technique, in which the spatial location of biopsy-trajectory was digitally recorded (Koelis), was carried out. A pair of diagnostic (1st-look) and surveillance (2nd-look) biopsy were performed per subject (n = 25), with median interval of 12 months. The documented biopsy-trajectory was used as a target to guide the re-visiting biopsy from the documented cancer focus, as well as the targeted field-biopsy from the un-sampled prostatic field adjacent to negative diagnostic biopsies. The accuracy of re-visiting biopsy and biopsy-derived CCP signatures were evaluated in the pair of the serial biopsy-cores.

RESULTS

The 1st-look-biopsy revealed a total of 43 cancer lesions (1.7 per patient). The accuracy of re-visiting cancer was 86% (37/43) per lesion, 76% (65/86) per core, and 80% (20/25) per patient. This technology also provided an opportunity for 3D-targeted field-biopsy in order to potentially minimize sampling errors. The CCP gene-panel of the 1st-look (-0.59) versus 2nd-look (-0.37) samples had no significant difference (P = 0.4); which suggested consistency in the molecular signature of the known cancer foci during the short-time interval of median 12 months. Any change in CCP of the same cancer foci would be likely due to change in sampling location from the less to more significant portion in the cancer foci rather than true molecular progression. The study limitations include a small number of the patients.

CONCLUSION

The 3D-documented biopsy-mapping technology achieved an encouraging re-sampling accuracy of 86% from the known prostate cancer foci, allowing the serial analysis of biopsy-derived CCP signatures.

Evaluation of models predicting insignificant prostate cancer to select men for active surveillance of prostate cancer

BACKGROUND

In an era of personalized medicine, individualized risk assessment using easily available tools on the internet and the literature are appealing. However, uninformed use by clinicians and the public raises potential problems. Herein, we assess the performance of published models to predict insignificant prostate cancer (PCa), using a multi-national low-risk population that may be considered for active surveillance (AS) based on contemporary practice.

METHODS

Data on men suitable for AS but undergoing upfront radical prostatectomy were pooled from three international academic institutions in Cambridge (UK), Toronto (Canada) and Melbourne (Australia). Four predictive models identified from literature review were assessed for their ability to predict the presence of four definitions of insignificant PCa. Evaluation was performed using area under the curve (AUC) of receiver operating characteristic curves and Brier scores for discrimination, calibration curves and decision curve analysis.

RESULTS

A cohort of 460 men meeting the inclusion criteria of all four nomograms was identified. The highest AUCs calculated for any of the four models ranged from 0.618 to 0.664, suggesting weak positive discrimination at best. Models had best discriminative ability for a definition of insignificant disease characterized by organ-confined Gleason score ⩽6 with a total volume ⩽0.5 ml or 1.3 ml. Calibration plots showed moderate range of predictive ability for the Kattan model though this model did not perform well at decision curve analysis.

CONCLUSIONS

External assessment of models predicting insignificant PCa showed moderate performance at best. Uninformed interpretation may cause undue anxiety or false reassurance and they should be used with caution.

Diagnostic prostate biopsy performed in a non-academic center increases the risk of re-classification at confirmatory biopsy for men considering active surveillance for prostate cancer

BACKGROUND

To examine whether diagnostic biopsy (B1), for patients on active surveillance (AS) for prostate cancer, performed at an outside referral centre (external) compared with our in-house tertiary center (internal), increased the risk of re-classification on the second (confirmatory) biopsy (B2).

METHODS

Patients on AS were identified from our tertiary center database (1997-2012) with PSA<10, Gleason sum (GS) ⩽6, clinical stage ⩽cT2, ⩽3 positive cores, <50% of single core involved, age ⩽75 years and having a B2. Patients who had <10 cores at B1 and delay in B2 >24 mo were excluded. Depending on center where B1 was performed, men were dichotomized to internal or external groups. All B2 were performed internally. Multivariate logistic regression examined if external B1 was a predictor of re-classification at B2.

RESULTS

A total of 375 patients were divided into external (n=71, 18.9%) and internal groups (n=304, 81.1%). At B2, more men in the external group re-classified (26.8%) compared with the internal group (13.8%) (P=0.008). On multivariate analysis, external B1 predicted grade-related re-classification (odds ratio (OR) 4.14, confidence interval (CI) 2.01-8.54, P<0.001) and volume-related re-classification (OR 3.43, CI 1.87-6.25, P<0.001). Other significant predictors for grade-related re-classification were age (OR 2.13 per decade, CI 1.32-3.57, P<0.001), PSA density (OR 2.56 per unit, CI 1.44-4.73, P<0.001), maximum % core involvement (OR 1.04 per percentage point, CI 1.01-1.09, P=0.02) and time between B1 and B2 (OR 1.43 per 6 months, CI 1.21-1.71, P<0.001).

CONCLUSION

At our institution, patients on AS who had their initial B1 performed externally were more likely to have adverse pathological features and re-classify on internal B2.

Active surveillance in patients with a PSA >10 ng/mL

INTRODUCTION

The use of prostate-specific antigen (PSA) in active surveillance (AS) for prostate cancer is controversial. Some consider it an unreliable marker and others as sufficient evidence to exclude patients from AS. We analyzed our cohort of AS patients with a PSA over 10 ng/mL.

METHODS

We included patients who had clinical T1c-T2a Gleason ≤6 disease, and ≤3 positive cores with ≤50% core involvement at diagnostic biopsy and ≥2 total biopsies. Patients were divided into 3 groups: (1) those with baseline PSA >10 ng/mL, (2) those with a PSA rise >10 ng/mL during follow-up; and (3) those with a PSA <10 ng/mL throughout AS. Adverse histology was defined as biopsy parameters exceeding the entry criteria limits. We further compared this cohort to a concurrent institutional cohort with equal biopsy parameters treated with immediate radical prostatectomy.

RESULTS

Our cohort included 698 patients with a median follow-up of 46.2 months. In total, 82 patients had a baseline PSA >10 ng/mL and 157 had a PSA rise >10 ng/mL during surveillance. No difference in adverse histology incidence was detected between groups (p = 0.3). Patients with a PSA greater than 10 were older and had higher prostate volumes. Hazard ratios for groups with a PSA >10 were protective against adverse histology. Larger prostate volume and minimal core involvement appear as factors related to this successful selection of patients to be treated with AS.

CONCLUSION

These results suggest that a strict cut-off PSA value for all AS patients is unwarranted and may result in overtreatment. Though lacking long-term data and validation, AS appears safe in select patients with a PSA >10 ng/mL and low volume Gleason 6 disease.

Can we deliver randomized trials of focal therapy in prostate cancer?

Tissue-preserving focal therapies, such as brachytherapy, cryotherapy, high-intensity focused ultrasound and photodynamic therapy, aim to target individual cancer lesions rather than the whole prostate. These treatments have emerged as potential interventions for localized prostate cancer to reduce treatment-related adverse-effects associated with whole-gland treatments, such as radical prostatectomy and radiotherapy. In this article, the Prostate Cancer RCT Consensus Group propose that a novel cohort-embedded randomized controlled trial (RCT) would provide a means to study men with clinically significant localized disease, which we defined on the basis of PSA level (≤ 15 ng/ml or ≤ 20 ng/ml), Gleason grade (Gleason pattern ≤ 4 + 4 or ≤ 4 + 3) and stage (≤ cT2cN0M0). This RCT should recruit men who stand to benefit from treatment, with the control arm being whole-gland surgery or radiotherapy. Composite outcomes measuring rates of local and systemic salvage therapies at 3-5 years might best constitute the basis of the primary outcome on which to change practice.

Regular transition zone biopsy during active surveillance for prostate cancer may improve detection of pathological progression

PURPOSE

We investigated the frequency of cancer and pathological progression in transition zone biopsies in men undergoing multiple rebiopsies while on active surveillance.

MATERIALS AND METHODS

Eligibility criteria of the active surveillance prostate cancer database (1997 to 2012) at our tertiary center includes prostate specific antigen 10 ng/ml or less, cT2 or less, no Gleason grade 4 or 5, 3 or fewer positive cores, no core with greater than 50% involvement, patient age 75 years or less and 1 or more biopsies after initial diagnostic biopsy. We excluded from analysis men with fewer than 10 cores at diagnostic biopsy and/or confirmatory biopsy greater than 24 months after diagnostic biopsy. Multiparametric magnetic resonance imaging was performed selectively to investigate incongruity between prostate specific antigen and biopsy findings. Pathological progression was defined by grade and/or volume (greater than 50% of core involved). Transition zone progression was subdivided into exclusively transition zone and combined transition zone (transition and peripheral zones). A multivariate Cox proportional hazards model was used to determine predictors of transition zone progression.

RESULTS

A total of 392 men were considered in analysis. Median followup was 45.5 months. At each biopsy during active surveillance (confirmatory biopsy to biopsy 5+) there were transition zone positive cores in 18.6% to 26.7% of cases, all transition zone progression in 5.9% to 11.1% and exclusively transition zone progression in 2.7% to 6.7%. Volume related progression was noted more frequently than grade related progression (24 vs 9 cases). Predictors of only transition zone progression were the maximum percent in a single core (HR 1.99, 95% CI 1.30-3.04, p = 0.002) and cancer on magnetic resonance imaging (HR 3.19, 95% CI 1.23-8.27, p = 0.02).

CONCLUSIONS

Across multiple active surveillance biopsies 2.7% to 6.7% of men had only transition zone progression. We recommend that transition zone biopsy be considered in all men at confirmatory biopsy. Positive magnetic resonance imaging findings or a high percent of core involvement may subsequently be useful to identify patients at risk.

Targeted prostate biopsy in select men for active surveillance: do the Epstein criteria still apply?

PURPOSE

Established in 1994, the Epstein histological criteria (Gleason score 6 or less, 2 or fewer cores positive and 50% or less of any core) have been widely used to select men for active surveillance. However, with the advent of targeted biopsy, which may be more accurate than conventional biopsy, we reevaluated the likelihood of reclassification upon confirmatory rebiopsy using multiparametric magnetic resonance imaging-ultrasound fusion.

MATERIALS AND METHODS

We identified 113 men enrolled in active surveillance at our institution who met Epstein criteria and subsequently underwent confirmatory targeted biopsy via multiparametric magnetic resonance imaging-ultrasound fusion. Median patient age was 64 years, median prostate specific antigen was 4.2 ng/ml and median prostate volume was 46.8 cc. Targets or regions of interest on multiparametric magnetic resonance imaging-ultrasound fusion were graded by suspicion level and biopsied at 3 mm intervals along the longest axis (median 10.5 mm). Also, 12 systematic cores were obtained during confirmatory rebiopsy. Our reporting is consistent with START (Standards of Reporting for MRI-targeted Biopsy Studies) criteria.

RESULTS

Confirmatory fusion biopsy resulted in reclassification in 41 men (36%), including 26 (23%) due to Gleason grade 6 or greater and 15 (13%) due to high volume Gleason 6 disease. When stratified by suspicion on multiparametric magnetic resonance imaging-ultrasound fusion, the likelihood of reclassification was 24% to 29% for target grade 0 to 3, 45% for grade 4 and 100% for grade 5 (p=0.001). Men with grade 4 and 5 vs lower grade targets were greater than 3 times more likely to be reclassified (OR 3.2, 95% CI 1.4-7.1, p=0.006).

CONCLUSIONS

Upon confirmatory rebiopsy using multiparametric magnetic resonance imaging-ultrasound fusion men with high suspicion targets on imaging were reclassified 45% to 100% of the time. Criteria for active surveillance should be reevaluated when multiparametric magnetic resonance imaging-ultrasound fusion guided prostate biopsy is used.