Baseline Prostate-Specific Antigen Levels in Midlife Predict Lethal Prostate Cancer

Trichomonas vaginalis infection and prostate-specific antigen concentration: Insights into prostate involvement and prostate disease risk

BACKGROUND

The protist Trichomonas vaginalis causes a common, sexually transmitted infection and has been proposed to contribute to the development of chronic prostate conditions, including benign prostatic hyperplasia and prostate cancer. However, few studies have investigated the extent to which it involves the prostate in the current antimicrobial era. We addressed this question by investigating the relation between T. vaginalis antibody serostatus and serum prostate-specific antigen (PSA) concentration, a marker of prostate infection, inflammation, and/or cell damage, in young, male, US military members.

METHODS

We measured T. vaginalis serum IgG antibodies and serum total PSA concentration in a random sample of 732 young, male US active duty military members. Associations between T. vaginalis serostatus and PSA were investigated by linear regression.

RESULTS

Of the 732 participants, 341 (46.6%) had a low T. vaginalis seropositive score and 198 (27.0%) had a high score, with the remainder seronegative. No significant differences were observed in the distribution of PSA by T. vaginalis serostatus. However, slightly greater, nonsignificant differences were observed when men with high T. vaginalis seropositive scores were compared with seronegative men, and when higher PSA concentrations were examined (≥0.70 ng/mL). Specifically, 42.5% of men with high seropositive scores had a PSA concentration greater than or equal to 0.70 ng/mL compared with 33.2% of seronegative men (adjusted P = .125).

CONCLUSIONS

Overall, our findings do not provide strong support for prostate involvement during T. vaginalis infection, although our suggestive positive findings for higher PSA concentrations do not rule out this possibility entirely. These suggestive findings may be relevant for prostate condition development because higher early- to mid-life PSA concentrations have been found to predict greater prostate cancer risk later in life.

Prostate cancer screening in low- and middle-income countries: the Mexican case

Prostate-specific antigen (PSA)-based early detection for prostate cancer is the subject of intense debate. Implementation of organized prostate cancer screening has been challenging, in part because the PSA test is so amenable to opportunistic screening. To the extent that access to cancer screening tests increases in low- and middle-income countries (LMICs), there is an urgent need to thoughtfully evaluate existing and future cancer screening strategies to ensure benefit and control costs. We used Mexico's prostate cancer screening efforts to illustrate the challenges LMICs face. We provide five considerations for policymakers for a smarter approach and implementation of PSA-based screening.

Would You Recommend Prostate-Specific Antigen Screening for This Patient?: Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Prostate cancer is the third most common cancer type in the United States overall, accounting for 9.5% of new cancer cases and 5% of cancer deaths. The goal of prostate-specific antigen (PSA)-based screening is to identify early-stage disease that can be treated successfully. The U.S. Preventive Services Task Force (USPSTF) reviewed evidence on the benefits and harms of PSA-based screening and treatment of screen-detected prostate cancer. It found that PSA-based screening in men aged 55 to 69 years prevents approximately 1.3 deaths from prostate cancer over 13 years per 1000 men screened and 3 cases of metastatic cancer per 1000 men screened, with no reduction in all-cause mortality. No benefit was found for PSA-based screening in men aged 70 years and older. On the basis of its review, the USPSTF concluded that the decision for men aged 55 to 69 years to have PSA-based screening should be an individual one and should include a discussion of the potential benefits and harms. Here, 2 experts-an internist and a urologist-discuss the key points of a shared decision-making conversation about PSA-based prostate cancer screening, the PSA-based screening strategy that optimizes benefit and minimizes harm, and the PSA threshold at which they would recommend further diagnostic testing.

Structured Population-based Prostate-specific Antigen Screening for Prostate Cancer: The European Association of Urology Position in 2019

Prostate cancer (PCa) is one of the first three causes of cancer mortality in Europe. Screening in asymptomatic men (aged 55-69yr) using prostate-specific antigen (PSA) is associated with a migration toward lower staged disease and a reduction in cancer-specific mortality. By 20yr after testing, around 100 men need to be screened to prevent one PCa death. While this ratio is smaller than for breast and colon cancer, the long natural history of PCa means many men die from other causes. As such, the nonselective use of PSA testing and radical treatments can lead to overdiagnosis and overtreatment. The European Association of Urology (EAU) supports measures to encourage appropriate PCa detection through PSA testing, while reducing overdiagnosis and overtreatment. These goals may be achieved using personalized risk-stratified approaches. For diagnosis, the greatest benefit from early detection is likely to come in men assessed using baseline PSA levels at the age of 45yr to individualize screening intervals. Multiparametric magnetic resonance imaging as well as risk calculators based on family history, ethnicity, digital rectal examination, and prostate volume should be considered to triage the need for biopsy, thus reducing the risk of overdiagnosis. For treatment, the EAU advocates balancing patient's life expectancy and cancer's mortality risk when deciding an approach. Active surveillance is encouraged in well-informed patients with low-risk and some intermediate-risk cancers, as it decreases the risks of overtreatment without compromising oncological outcomes. Conversely, the EAU advocates radical treatment in suitable men with more aggressive PCa. Multimodal treatment should be considered in locally advanced or high-grade cancers. PATIENT SUMMARY: Implementation of prostate-specific antigen (PSA)-based screening should be considered at a population level. Men at risk of prostate cancer should have a baseline PSA blood test (eg, at 45yr). The level of this test, combined with family history, ethnicity, and other factors, can be used to determine subsequent follow-up. Magnetic resonance imaging scans and novel biomarkers should be used to determine which men need biopsy and how any cancers should be treated.

Baseline Prostate-specific Antigen Level in Midlife and Aggressive Prostate Cancer in Black Men

BACKGROUND

Prostate-specific antigen (PSA) measurement in midlife predicts long-term prostate cancer (PCa) mortality among white men.

OBJECTIVE

To determine whether baseline PSA level during midlife predicts risk of aggressive PCa in black men.

DESIGN, SETTING, AND PARTICIPANTS

Nested case-control study among black men in the Southern Community Cohort Study recruited between 2002 and 2009. A prospective cohort in the southeastern USA with recruitment from community health centers. A total of 197 incident PCa patients aged 40-64 yr at study entry and 569 controls matched on age, date of blood draw, and site of enrollment. Total PSA was measured in blood collected and stored at enrollment.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Total and aggressive PCa (91 aggressive: Gleason ≥7, American Joint Committee on Cancer stage III/IV, or PCa-specific death). Exact conditional logistic regression estimated odds ratios (ORs) with 95% confidence intervals (CIs) for PCa by category of baseline PSA.

RESULTS AND LIMITATIONS

Median PSA among controls was 0.72, 0.80, 0.94, and 1.03ng/ml for age groups 40-49, 50-54, 55-59, and 60-64 yr, respectively; 90th percentile levels were 1.68, 1.85, 2.73, and 3.33ng/ml. Furthermore, 95% of total and 97% of aggressive cases had baseline PSA above the age-specific median. Median follow-up was 9 yr. The OR for total PCa comparing PSA >90th percentile versus ≤median was 83.6 (95% CI, 21.2-539) for 40-54 yr and 71.7 (95% CI, 23.3-288) for 55-64 yr. For aggressive cancer, ORs were 174 (95% CI, 32.3-infinity) for 40-54 yr and 51.8 (95% CI, 11.0-519) for 55-64 yr. A composite endpoint of aggressive PCa based on stage, grade, and mortality was used and is a limitation.

CONCLUSIONS

PSA levels in midlife strongly predicted total and aggressive PCa among black men. PSA levels among controls were similar to those among white controls in prior studies.

PATIENT SUMMARY

Prostate-specific antigen (PSA) level during midlife strongly predicted future development of aggressive prostate cancer among black men. Targeted screening based on a midlife PSA might identify men at high risk while minimizing screening in those men at low risk.

Sustained influence of infections on prostate-specific antigen concentration: An analysis of changes over 10 years of follow-up

BACKGROUND

To extend our previous observation of a short-term rise in prostate-specific antigen (PSA) concentration, a marker of prostate inflammation and cell damage, during and immediately following sexually transmitted and systemic infections, we examined the longer-term influence of these infections, both individually and cumulatively, on PSA over a mean of 10 years of follow-up in young active duty U.S. servicemen.

METHODS

We measured PSA in serum specimens collected in 1995-7 (baseline) and 2004-6 (follow-up) from 265 men diagnosed with chlamydia (CT), 72 with gonorrhea (GC), 37 with non-chlamydial, non-gonococcal urethritis (NCNGU), 58 with infectious mononucleosis (IM), 91 with other systemic or non-genitourinary infections such as varicella; and 125-258 men with no infectious disease diagnoses in their medical record during follow-up (controls). We examined the influence of these infections on PSA change between baseline and follow-up.

RESULTS

The proportion of men with any increase in PSA (>0 ng/mL) over the 10-year average follow-up was significantly higher in men with histories of sexually transmitted infections (CT, GC, and NCNGU; 67.7% vs 60.8%, P = 0.043), systemic infections (66.7% vs 54.4%, P = 0.047), or any infections (all cases combined; 68.5% vs 54.4%, P = 0.003) in their military medical record compared to controls.

CONCLUSIONS

While PSA has been previously shown to rise during acute infection, these findings demonstrate that PSA remains elevated over a longer period. Additionally, the overall infection burden, rather than solely genitourinary-specific infection burden, contributed to these long-term changes, possibly implying a role for the cumulative burden of infections in prostate cancer risk.

Prostate-Specific Antigen Trends Predict the Probability of Prostate Cancer in a Very Large U.S. Veterans Affairs Cohort

If prostate-specific antigen (PSA) trends help identify elevated prostate cancer (PCa) risk, they might provide early warning of progressing cancer for further evaluation and justify annual testing. Our objective was to determine whether PSA trends predict PCa likelihood. A biopsy cohort of 361,657 men was obtained from a Veterans Affairs database (1999–2012). PSA trends were estimated for the 310,458 men with at least 2 PSA tests prior to biopsy. Cancer tumors may grow exponentially with cells doubling periodically. We hypothesized that PSA from prostate cancer grows exponentially above a no cancer baseline. We estimated PSA trends on that basis along with five descriptive variables: last PSA before biopsy, growth rate in PSA from cancer above a baseline, PSA variability around the trend, number of PSA tests, and time span of tests. PSA variability is a new variable that measures percentage deviations of PSA tests from estimated trends with 0% variability for a smoothly increasing trend. Logistic regression models were used to estimate relationships between the probability of PCa at biopsy and the trend variables and age. All five PSA trend variables and age were significant predictors of prostate cancer at biopsy (p < 0.0001). An overall logistic regression model achieved an AUC of 0.67 for men with at least 4 tests over at least 3 years, which was a substantial improvement over a single PSA (AUC 0.58). High probability of PCa was associated with low PSA variability (smooth trends), high PSA, high growth rate, many tests over a long time-span and older age. For example, at 4.0 PSA the probability of cancer is 32% for 1 PSA test and increases to 68% for 8 tests over 7 years with smooth, fast growth (0% variability and 50% exponential growth). Our results show that smooth, fast exponential growth in PSA above a baseline predicts an increased probability of PCa. The probability increases as smooth (low variability) trends are observed for more tests over a longer time span, which makes annual testing worth considering. Worrisome PSA trends might be used to trigger further evaluation and continued monitoring of the trends—even at low PSA levels.

Twenty-year Risk of Prostate Cancer Death by Midlife Prostate-specific Antigen and a Panel of Four Kallikrein Markers in a Large Population-based Cohort of Healthy Men

BACKGROUND

Prostate-specific antigen (PSA) screening reduces prostate cancer deaths but leads to harm from overdiagnosis and overtreatment.

OBJECTIVE

To determine the long-term risk of prostate cancer mortality using kallikrein blood markers measured at baseline in a large population of healthy men to identify men with low risk for prostate cancer death.

DESIGN, SETTING, PARTICIPANTS

Study based on the Malmö Diet and Cancer cohort enrolling 11 506 unscreened men aged 45-73 yr during 1991-1996, providing cryopreserved blood at enrollment and followed without PSA screening to December 31, 2014. We measured four kallikrein markers in the blood of 1223 prostate cancer cases and 3028 controls.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Prostate cancer death (n=317) by PSA and a prespecified statistical model based on the levels of four kallikrein markers.

RESULTS AND LIMITATIONS

Baseline PSA predicted prostate cancer death with a concordance index of 0.86. In men with elevated PSA (≥2.0ng/ml), predictive accuracy was enhanced by the four-kallikrein panel compared with PSA (0.80 vs 0.73; improvement 0.07; 95% confidence interval 0.04, 0.10). Nearly half of men aged 60+ yr with elevated PSA had a four-kallikrein panel score of <7.5%, translating into 1.7% risk of prostate cancer death at 15 yr-a similar estimate to that of a man with a PSA of 1.6ng/ml. Men with a four-kallikrein panel score of ≥7.5% had a 13% risk of prostate cancer death at 15 yr.

CONCLUSIONS

A prespecified statistical model based on four kallikrein markers (commercially available as the 4Kscore) reclassified many men with modestly elevated PSA, to have a low long-term risk of prostate cancer death. Men with elevated PSA but low scores from the four-kallikrein panel can be monitored rather than being subject to biopsy.

PATIENT SUMMARY

Men with elevated prostate-specific antigen (PSA) are often referred for prostate biopsy. However, men with elevated PSA but low scores from the four-kallikrein panel can be monitored rather than being subject to biopsy.

Prostate Cancer: Update on Early Detection and New Biomarkers

Screening and early treatment of prostate cancer (PCa) has recently come under scrutiny due to the rates of overdiagnosis of low risk cancer. Randomized trials, including ERSPC and PLCO, have informed our understanding of the survival benefit provided by systematic PCa screening with serum prostate-specific antigen (PSA). To reduce the number of patients diagnosed with indolent disease, new adjuvant risk stratification tests have become available.

Prostate cancer screening-when to start and how to screen?

Prostate-specific antigen (PSA) screening reduces prostate cancer (PCa) mortality; however such screening may lead to harm in terms of overdiagnosis and overtreatment. Therefore, upfront shared decision making involving a discussion about pros and cons between a physician and a patient is crucial. Total PSA remains the most commonly used screening tool and is a strong predictor of future life-threatening PCa. Currently there is no strong consensus on the age at which to start PSA screening. Most guidelines recommend PSA screening to start no later than at age 55 and involve well-informed men in good health and a life expectancy of at least 10–15 years. Some suggest to start screening in early midlife for men with familial predisposition and men of African-American descent. Others suggest starting conversations at age 45 for all men. Re-screening intervals can be risk-stratified as guided by the man’s age, general health and PSA-value; longer intervals for those at lower risk and shorter intervals for those at higher risk. Overdiagnosis and unnecessary biopsies can be reduced using reflex tests. Magnetic resonance imaging in the pre-diagnostic setting holds promise in pilot studies and large-scale prospective studies are ongoing.

Polygenic hazard score to guide screening for aggressive prostate cancer: development and validation in large scale cohorts

OBJECTIVES

To develop and validate a genetic tool to predict age of onset of aggressive prostate cancer (PCa) and to guide decisions of who to screen and at what age.

DESIGN

Analysis of genotype, PCa status, and age to select single nucleotide polymorphisms (SNPs) associated with diagnosis. These polymorphisms were incorporated into a survival analysis to estimate their effects on age at diagnosis of aggressive PCa (that is, not eligible for surveillance according to National Comprehensive Cancer Network guidelines; any of Gleason score ≥7, stage T3-T4, PSA (prostate specific antigen) concentration ≥10 ng/L, nodal metastasis, distant metastasis). The resulting polygenic hazard score is an assessment of individual genetic risk. The final model was applied to an independent dataset containing genotype and PSA screening data. The hazard score was calculated for these men to test prediction of survival free from PCa.

SETTING

Multiple institutions that were members of international PRACTICAL consortium.

PARTICIPANTS

All consortium participants of European ancestry with known age, PCa status, and quality assured custom (iCOGS) array genotype data. The development dataset comprised 31 747 men; the validation dataset comprised 6411 men.

MAIN OUTCOME MEASURES

Prediction with hazard score of age of onset of aggressive cancer in validation set.

RESULTS

In the independent validation set, the hazard score calculated from 54 single nucleotide polymorphisms was a highly significant predictor of age at diagnosis of aggressive cancer (z=11.2, P<10-16). When men in the validation set with high scores (>98th centile) were compared with those with average scores (30th-70th centile), the hazard ratio for aggressive cancer was 2.9 (95% confidence interval 2.4 to 3.4). Inclusion of family history in a combined model did not improve prediction of onset of aggressive PCa (P=0.59), and polygenic hazard score performance remained high when family history was accounted for. Additionally, the positive predictive value of PSA screening for aggressive PCa was increased with increasing polygenic hazard score.

CONCLUSIONS

Polygenic hazard scores can be used for personalised genetic risk estimates that can predict for age at onset of aggressive PCa.

The prostate cancer screening clinic in the Bahamas: a model for low- and middle-income countries

PURPOSE

Grand Bahama (pop. 51,000) is an island within the Bahamas archipelago. A local chapter of International Us TOO Prostate Cancer Support Group (UTGB) has led an annual community-based prostate cancer screening clinic in Grand Bahama each September since 2009. Features of this initiative, characteristics of attendees, and a description of found cancers were summarized to determine the clinic's value and to guide improvements.

METHOD

We analyzed the established clinic from 2012 to 2015, wherein UTGB attracted corporate funding, volunteers managed clinics, and health professionals provided healthcare services. An explicit algorithm was used to sort clients by age, comorbidities, and findings from digital rectal examinations, and prostate-specific antigen (PSA) values, to determine which clients would undergo secondary assessment and prostate biopsy.

RESULTS

Overall, 1,844 males were registered (mean age 57.6 years), and only 149 men attended on more than one occasion for a total of 1,993 clinic visit. The urologist reviewed 315 men in secondary follow-up, for elevated PSA and/or an abnormal digital rectal examination. Of these, 45 men fulfilled criteria for trans-rectal ultrasound biopsy, and there were 40 found cases of prostate cancer, for a positive-predictive value of 89%. By D'Amico risk-stratification, these 40 cases were low (10%), intermediate (40%), and high risk (50%). The urologist counseled all 40 cases and facilitated access to standard care.

CONCLUSION

This study suggests that low-resource countries can advance cost-effective screening clinics, apply policy guidelines, and provide services within acceptable standards of care. It is the expectation, with a sustained effort and community participation over the ensuing years, that earlier disease presentation will occur and, consequently, a concomitant decrease in the disease-specific mortality.

Approach to the Patient with High-Risk Prostate Cancer

Men classified as having high-risk prostate cancer warrant treatment because durable outcomes can be achieved. Judicious use of imaging and considerations of risk factors are essential when caring for men with high-risk disease. Radical prostatectomy, radiation therapy, and androgen deprivation therapy all play pivotal roles in the management of men with high-risk disease, and potentially in men with metastatic disease. The optimal combinations of therapeutic regimens are an evolving area of study and future work looking into therapies for men with high-risk disease will remain critical.

A randomized trial of early detection of clinically significant prostate cancer (ProScreen): study design and rationale

The current evidence of PSA-based prostate cancer screening shows a reduction in cause-specific mortality, but with substantial overdiagnosis. Recently, new developments in detection of clinically relevant prostate cancer include multiple kallikreins as biomarkers besides PSA, and multiparametric magnetic resonance imaging (mpMRI) for biopsy decision. They offer opportunities for improving the outcomes in screening, particularly reduction in overdiagnosis and higher specificity for potentially lethal cancer. A population-based randomized screening trial will be started, with 67,000 men aged 55-67 years at entry. A quarter of the men will be allocated to the intervention arm, and invited to screening. The control arm will receive no intervention. All men in the screening arm will be offered a serum PSA determination. Those with PSA of 3 ng/ml or higher will have an additional multi-kallikrein panel and those with indications of increased risk of clinically relevant prostate cancer will undergo mpMRI. Men with a malignancy-suspect finding in MRI are referred to targeted biopsies. Screening interval is 6 years for men with baseline PSA < 1.5 ng/ml, 4 years with PSA 1.5-3.0 and 2 years if initial PSA > 3. The main outcome of the trial is prostate cancer mortality, with analysis at 10 and 15 years. The statistical power is sufficient for detecting a 28% reduction at 10 years and 22% at 15 years. The proposed study has the potential to provide the evidence to justify screening as a public health policy if mortality benefit can be sustained with substantially reduced overdiagnosis.

Genomic tests to guide prostate cancer management following diagnosis

INTRODUCTION

Prostate cancer (PCa) is a common cancer in men, but variable clinical behaviors make its management challenging. Risk stratification is a key issue in disease management. Patient-tailored strategies are strongly advocated to reduce unnecessary treatment while maximizing the oncological outcomes of patient who need active treatment in the primary, adjuvant or salvage setting. Recently, tissue-based biomarkers or genomic tests have become available to improve the clinical decision-making. Areas covered: In this review, the authors present recent evidence about these tissue-based biomarkers, discussing the application of each of them in the clinical setting, focusing on the tests aimed to provide a better risk stratification and to guide decision-making after the diagnosis of PCa (i.e. OncotypeDX^Ⓡ, Prolaris^Ⓡ, ProMark^Ⓡ, Ki-67, Decipher^Ⓡ, PTEN, PORTOS, AR-V7 and DNA repair gene mutations). Expert commentary: Even if the clinicopathologic features are still the most frequently-used predictors of disease progression, these tools can be helpful in decision-making at every stage of the PCa management. Actually, OncotypeDX^Ⓡ, Prolaris^Ⓡ and Decipher^Ⓡ are recommended in the clinical setting by guidelines at different steps of PCa management. Consequently, further studies are indispensable to better tailor the right therapy for the right patient and at the right time.

Prostate cancer screening practices in a large, integrated health system: 2007-2014

OBJECTIVES

To assess prostate cancer screening practices in primary care since the initial United States Preventive Services Task Force (USPSTF) recommendation against prostate-specific antigen (PSA) testing for older men, and to assess primary provider variation associated with prostate cancer screening.

PATIENTS AND METHODS

Our study population included 160 211 men aged ≥40 years with at least one visit to a primary care clinic in any of the study years in a large, integrated health system. We conducted a retrospective cohort study using electronic medical record data from January 2007 to December 2014. Yearly rates of screening PSA testing by primary care providers (PCPs), rates of re-screening, and rates of prostate biopsies were assessed.

RESULTS

Annual PSA-screening testing declined from 2007 to 2014 in all age groups, as did biennial and quadrennial screening. Yearly rates declined for men aged ≥70 years, from 22.8% to 8.9%; ages 50-69 years, from 39.2% to 20%; and ages 40-49 years, from 11% to 4.6%. Overall rates were lower for African-American (A-A) men vs non-A-A men; for men with a family history of prostate cancer, rates were similar or slightly higher than for those without a family history. PCP variation associated with ordering of PSA testing did not substantially change after the USPSTF recommendations. While the number of men screened and rates of follow-up prostate cancer screening declined in 2011-2014 compared to 2007-2010, similar re-screening rates were noted for men aged 45-75 years with initial PSA levels of <1 ng/mL or 1-3 ng/mL in both the earlier and later cohorts. For men aged >75 years with initial PSA levels of <3 ng/mL screened in both cohorts, follow-up screening rates were similar. Rates of prostate biopsy declined for men aged ≥70 years in 2014 compared to 2007. For men who had PSA screening, rates of first prostate biopsy increased in later years for A-A men and men with a family history of prostate cancer.

CONCLUSIONS

Prostate cancer screening declined from 2007 to 2014 even in higher-risk groups and follow-up screening rates were not related to previous PSA level. However, rates of first prostate biopsy in men who were screened with a PSA test were higher for men with an increased risk of prostate cancer in later years. Variation in PSA testing was noted among PCPs. Future work should further explore sources of variation in screening practices and implementation of risk-based strategies for prostate cancer screening in primary care.

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.