The Contemporary Concept of Significant Versus Insignificant Prostate Cancer
ABSTRACT 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.
To review the definition of Ins-PCa, its incidence, and the clinical impact of Ins-PCa on the contemporary management of PCa.
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.
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.
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.
- Open Access Surgery 01/2011; DOI:10.2147/OAS.S14557
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ABSTRACT: Recent advances in tumor biology have made remarkable achievements in the development of therapy for metastatic castrate-resistant prostate cancer. These advances reflect a growing appreciation for the role of the tumor microenvironment in promoting prostate cancer progression. Prostate cancer is no longer viewed predominantly as a disease of abnormally proliferating epithelial cells but rather as a disease of complex interactions between prostate cancer epithelial cells (epithelial compartment) and the surrounding tissues (stromal compartment) in which they reside. For example, prostate cancers frequently metastasize to bone, an organ that contains a microenvironment rich in extracellular matrix proteins and stromal cells including hematopoietic cells, osteoblasts, osteoclasts fibroblasts, endothelial cells, adipocytes, immune cells, and mesenchymal stem cells. Multiple signaling pathways provide crosstalk between the epithelial and the stromal compartments to enhance tumor growth, including androgen receptor signaling, tyrosine kinase receptor signaling, and immune surveillance. The rationale to disrupt this "two-compartment" crosstalk has led to the development of drugs that target tumor stromal elements in addition to the cancer epithelial cell.CancerSpectrum Knowledge Environment 09/2011; 103(22):1665-75. DOI:10.1093/jnci/djr362 · 15.16 Impact Factor
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ABSTRACT: We designed and fully evaluated the performance of a nomogram to identify patients with prostate cancer who may be suitable for active surveillance. We developed a nomogram to predict the probability of minimal prostate cancer (total tumor volume less than 0.5 cc, organ confined disease and no Gleason pattern 4 or 5) using preoperative data on 2,525 Australian patients who underwent radical prostatectomy. Accuracy and error rates at multiple probability cutoffs were compared with those of contemporary Epstein criteria and the Prostate Cancer Research International: Active Surveillance trial inclusion criteria when applied to these patients. High risk disease was defined as 1 or more adverse characteristics (including positive surgical margins, seminal vesicle invasion, extracapsular extension, 50% or greater Gleason pattern 4/5 and/or tumor volume 4.0 cc or greater) at radical prostatectomy. Minimal cancer was confirmed in 152 men (6.0%) at prostatectomy. The bootstrap corrected predictive accuracy of our nomogram was 93.3% vs 89.1% and 91.0% for Prostate Cancer Research International: Active Surveillance and Epstein criteria, respectively. For men with a nomogram derived minimal cancer probability of 0% to 4.9%, 5.0% to 19.9%, 20.0% to 34.9%, 35.0% to 49.9% and 50.0% to 71.0% the rate of high risk disease was 70.8%, 37.8%, 22.4%, 9.0% and 3.8%, respectively. In contrast, the rate of high risk disease for men who met Prostate Cancer Research International: Active Surveillance and Epstein criteria were 17.1% and 13.9%, respectively. A detailed breakdown of the expected rates of false-positive results and high risk disease associated with the nomogram derived probability of minimal cancer would provide more complete information to clinicians and patients on which to base therapeutic clinical decisions for presumed early stage prostate cancer.The Journal of urology 09/2011; 186(5):1811-7. DOI:10.1016/j.juro.2011.06.060 · 3.75 Impact Factor