The Epstein Criteria Predict for Organ-Confined But Not Insignificant Disease and a High Likelihood of Cure at Radical Prostatectomy

Suitability of PSA-detected localised prostate cancers for focal therapy: experience from the ProtecT study

Background:

Contemporary screening for prostate cancer frequently identifies small volume, low-grade lesions. Some clinicians have advocated focal prostatic ablation as an alternative to more aggressive interventions to manage these lesions. To identify which patients might benefit from focal ablative techniques, we analysed the surgical specimens of a large sample of population-detected men undergoing radical prostatectomy as part of a randomised clinical trial.

Methods:

Surgical specimens from 525 men who underwent prostatectomy within the ProtecT study were analysed to determine tumour volume, location and grade. These findings were compared with information available in the biopsy specimen to examine whether focal therapy could be provided appropriately.

Results:

Solitary cancers were found in prostatectomy specimens from 19% (100 out of 525) of men. In addition, 73 out of 425 (17%) men had multiple cancers with a solitary significant tumour focus. Thus, 173 out of 525 (33%) men had tumours potentially suitable for focal therapy. The majority of these were small, well-differentiated lesions that appeared to be pathologically insignificant (38–66%). Criteria used to select patients for focal prostatic ablation underestimated the cancer's significance in 26% (34 out of 130) of men and resulted in overtreatment in more than half. Only 18% (24 out of 130) of men presumed eligible for focal therapy, actually had significant solitary lesions.

Conclusion:

Focal therapy appears inappropriate for the majority of men presenting with prostate-specific antigen-detected localised prostate cancer. Unifocal prostate cancers suitable for focal ablation are difficult to identify pre-operatively using biopsy alone. Most lesions meeting criteria for focal ablation were either more aggressive than expected or posed little threat of progression.

Insignificant Prostate Cancer: Charateristics and Predictive Factors

Introduction

The widespread screening for PSA has contributed to the increased incidence of prostate cancer (PCa), mostly identifying disease at earlier stages. Many of these patients will probably not require treatment because of the indolent course of the disease. The European Randomized Study of Screening for Prostate Cancer (ERSPC) has showed that 1410 men needed to be screened and 48 prostatectomies performed to prevent death. The aim of this study was to evaluate predictive factors of insignificant PCa in our experience.

Materials and Methods

We analyzed various preoperative clinical and biopsy findings of 225 consecutive patients who underwent prostatectomy from October 2007 to June 2010. The indication for biopsy was placed in presence of an abnormal rectal examination and/or suspected transrectal ultrasound and/or PSA >4 ng/ml. We consider insignificant a tumor with a volume ≤5% of the entire gland with a Gleason score ≤ 6, with no grades 4 or 5 and organ confined.

Results

The prevalence of potentially insignificant PCa in our experience was 12%. The preoperative findings of patients with insignificant PCa were significantly more favorable than the remaining cases with PCa not insignificant. Multivariate analysis did not reveal any independent predictors.

Conclusions

In our experience, in a population not screened for PCa, we have not identified any factors that can predict with certainty the insignificant nature of a tumor and, therefore, useful to start a patient on an active surveillance program.

Watchful waiting and active surveillance approach in patients with low risk localized prostatic cancer: an experience of out-patients clinic with 12-year follow-up

In this study we evaluated the safety of expectant approach in the patients with low risk prostate cancer in the reality of community based out-patients clinics. 48 men were enrolled into the study. The inclusion criteria were age ranged from 60 to 75 years and the Epstein criteria for low risk prostate cancer. Patients were managed expectantly while curative treatment was offered when indicated. Initial and final Charlson comorbidity index (CCI) and BMI were assessed for all men. Patients' median follow-up was 81.1 ± 29.1 years. During this study 41.7% of the patients chose active forms of treatment. Cancer was found in 20.8% (n-10) of our patients. Two first sessions of re-biopsy diagnosed 92% of T1c upgrading. Six men with CCI ≥2 died from concomitant disease and no one died from PCa. Significant correlation was found between BMI and final CCI ≥2 (p-0.001). Expectant approach can be considered as self alternative to active treatment model in selected group of patients with well differentiated PCa, however 20.8% of these patients are still at risk of having aggressive form of cancer. Expectant approach is particular beneficial for the patients with CCI 1-2 and high BMI.

The contemporary concept of significant versus insignificant prostate cancer

CONTEXT

The notion of insignificant prostate cancer (Ins-PCa) has progressively emerged in the past two decades. The clinical relevance of such a definition was based on the fact that low-grade, small-volume, and organ-confined prostate cancer (PCa) may be indolent and unlikely to progress to biologic significance in the absence of treatment.

OBJECTIVE

To review the definition of Ins-PCa, its incidence, and the clinical impact of Ins-PCa on the contemporary management of PCa.

EVIDENCE ACQUISITION

A review of the literature was performed using the Medline, Scopus, and Web of Science databases with no restriction on language up to September 2010. The literature search used the following terms: insignificant, indolent, minute, microfocal, minimal, low volume, low risk, and prostate cancer.

EVIDENCE SYNTHESIS

The most commonly used criteria to define Ins-PCa are based on the pathologic assessment of the radical prostatectomy specimen: (1) Gleason score ≤ 6 without Gleason pattern 4 or 5, (2) organ-confined disease, and (3) tumour volume<0.5 cm(3). Several preoperative criteria and prognostication tools for predicting Ins-PCa have been suggested. Nomograms are best placed to estimate the risk of progression on an individualised basis, but a substantial proportion of men with a high probability of harbouring Ins-PCa are at risk for pathologic understaging and/or undergrading. Thus, there is an ongoing need for identifying novel and more accurate predictors of Ins-PCa to improve the distinction between insignificant versus significant disease and thus to promote the adequate management of PCa patients at low risk for progression.

CONCLUSIONS

The exciting challenge of obtaining the pretreatment diagnostic tools that can really distinguish insignificant from significant PCa should be one of the main objectives of urologists in the following years to decrease the risk of overtreatment of Ins-PCa.

Epstein criteria for insignificant prostate cancer

Study Type - Prognosis (systematic review).

LEVEL OF EVIDENCE

2b. What's known on the subject? and What does the study add? Overtreatment of prostate cancer is a major problem in contemporary urological practice. The Epstein Criteria reduces overtreatment by identifying insignificant prostate cancers that may be amenable to surveillance therapy. This systematic review of the Epstein Criteria validation studies provides a collective insight into the application and accuracy of the Epstein Criteria to predict for insignificant prostate cancer across different institutions and geographies.

OBJECTIVE

• To review the accuracy of the Epstein Criteria for insignificant prostate cancer and to explore the effect of the modified Gleason classification system on this system.

METHODS

• We searched PubMed, EMBASE and the Cochrane Database using search terms 'Epstein Criteria', 'Prostate Cancer', 'Validation' and 'Insignificant Cancer' between 1994 to 2010 for validation articles. • These were divided into pre-2005 and post-2005 and concordances for organ-confined status, Gleason score ≤ 6 and insignificant cancer were analysed.

RESULTS

• A pre-2005 study showed concordance for insignificant prostate cancer, Gleason score ≤ 6 and organ-confined status at 84%, 90.3% and 91.6%, respectively. • Five post-2005 validation studies were concordant for insignificant cancer, Gleason score ≤ 6 and organ-confined status at 37-76%, 54.3-75.9% and 80.0-96.9%, respectively.

CONCLUSIONS

• The Epstein Criteria has a suboptimal accuracy for predicting for insignificant prostate cancer. • The modification to Gleason scoring may be responsible for a reduced accuracy over time. • However, significant heterogeneity in the validation studies means better quality validation studies are required.