Should follow-up biopsies for men on active surveillance for prostate cancer be restricted to limited templates?

Long-term use of 5-alpha-reductase inhibitors is safe and effective in men on active surveillance for prostate cancer

BACKGROUND

Although 5-alpha-reductase inhibitors (5ARIs) have been shown to benefit men with prostate cancer (PCa) on active surveillance (AS), their long-term safety remains controversial. Our objective is to describe the long-term association of 5ARI use with PCa progression in men on AS.

MATERIALS/SUBJECTS AND METHODS

The cohort of men with low-risk PCa was derived from a prospectively maintained AS database at the Princess Margaret (1995-2016). Pathologic, grade, and volume progression were the primary end points. Kaplan-Meier time-to-event analysis was performed and Cox proportional hazards regression was used to determine predictors of progression where 5ARI exposure was analyzed as a time-dependent variable. Patients who came off AS prior to any progression events were censored at that time.

RESULTS

The cohort included 288 men with median follow-up of 82 months (interquartile range: 37-120 months). Among non-5ARI users (n = 203); 114 men (56.2%) experienced pathologic progression compared with 24 men (28.2%) in the 5ARI group (n = 85), (p < 0.001). Grade and volume progression were higher in the non-5ARI group compared with the 5ARI group (n = 82; 40.4% vs. n = 19; 22.4% respectively, p = 0.003 for grade progression; n = 87; 43.1% and n = 15; 17.7%, respectively for volume progression p < 0.001). Lack of 5ARI use was independently positively associated with pathologic progression (HR: 2.65; CI: 1.65-4.24), grade progression (HR: 2.75; CI: 1.49-5.06), and volume progression (HR: 3.15; CI: 1.78-5.56). The frequency of progression to high-grade (Grade Group 4-5) tumors was not significantly different between the groups.

CONCLUSIONS

Use of 5ARIs diminished both grade and volume progression without an increased risk of developing Grade Groups 4-5 disease.

Variability in the multicentre National Registry in Active Surveillance; a questionnaire for urologists

BACKGROUND

Our main objective was to report the current use of active surveillance in Spain and to identify areas for potential improvement.

METHODS

A questionnaire generated by the Platform for Multicentre Studies of the Spanish Urology Association (AEU/PIEM/2014/0001, NCT02865330) was sent to all associate researchers from January to March 2016. The questionnaire included 7 domains covering various aspects of active surveillance.

RESULTS

Thirty-three of the 41 associate researchers responded to the questionnaire. Active surveillance is mainly controlled by the urology departments (87.9%). There was considerable heterogeneity in the classical clinical-pathological variables as selection criteria. Only 36.4% of the associate researchers used prostate-specific antigen density (PSAd). Multiparametric magnetic resonance imaging (mpMRI) was clearly underused as initial staging (6%). Only 27.3% of the researchers stated that their radiology colleagues had a high level of experience in mpMRI. In terms of the confirmation biopsy, most of the centres used the transrectal pathway, and only 2 out of 33 used the transperineal pathway or fusion software. Half of the researchers interviewed applied active treatment when faced with disease progression to Gleason 7 (3+4). There was no consensus on when to transition to an observation strategy.

CONCLUSIONS

The study showed the underutilisation of informed consent and quality-of-life questionnaires. PSAd was not included as a decisive element in the initial strategy for most researchers. There was a lack of confidence in the urologists' mpMRI experience and an underutilisation of the transperineal pathway. There was also no consensus on the follow-up protocols and active treatment criteria, confirming the need for prospective studies to analyse the role of mpMRI and biomarkers.

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.

An Increase in Gleason 6 Tumor Volume While on Active Surveillance Portends a Greater Risk of Grade Reclassification with Further Followup

PURPOSE

We evaluated the relative risk of later grade reclassification and outcomes of patients in whom high volume Gleason 6 prostate cancer develops while on active surveillance.

MATERIALS AND METHODS

A prospectively maintained database was used to identify patients on active surveillance between 1998 and 2013. Tumor volume was assessed based on the number of positive cores and proportion of core involvement. The chi-square and Fisher exact tests were used for analysis as appropriate. The primary end point was the development of grade reclassification, defined as grade only and/or grade and volume at the event biopsy.

RESULTS

A total of 555 men met the study inclusion criteria. Mean followup was 46 months. Overall 70 patients demonstrated an increase in tumor volume at or after biopsy 2. Compared to those men never experiencing volume or grade reclassification, prostate specific antigen at diagnosis was not significantly different (p=0.95), but median prostate volume was smaller in patients who demonstrated volume reclassification (p <0.001). The incidence of pure volume reclassification was 6.8%, 6.1% and 7.8% at biopsy 2, 3 and 4, respectively. Men with volume reclassification were more likely to experience later grade reclassification than those without at 33.3% vs 9.3%, respectively (p <0.0001).

CONCLUSIONS

While Gleason 6 prostate cancer has a favorable natural history, it appears that patients on active surveillance who experience volume reclassification are at substantially higher risk for grade reclassification. Thus, urologists should pay close attention to tumor core involvement, and monitoring should be adjusted accordingly for early volume reclassification in younger men and those in good health.

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.