Current clinical presentation and treatment of localized prostate cancer in the United States

Dosimetric Features of Ultra-Hypofractionated Intensity Modulated Proton Therapy for Prostate Cancer

Purpose

To report clinical and dosimetric characteristics of 5-fraction stereotactic ablative radiotherapy (SABR) using intensity modulated proton therapy (IMPT) for localized prostate cancer.

Materials and Methods

All patients receiving IMPT SABR from 2017 to 2021 for localized prostate cancer at our institution were included. Five fractions were delivered every other day to the prostate +/- seminal vesicles [clinical target volume (CTV)] with 3 mm/3% robustness. A 4-field arrangement with 2 anterior oblique and 2 opposed lateral beams was used in most patients (97%), and most (99%) had a retroprostatic hydrogel spacer.

Results

A total of 534 patients with low (14%), favorable intermediate (45%), unfavorable intermediate (36%), high (4.0%), or very high-risk (0.6%) disease are evaluated. Prescription dose was 36.25 Gy (31%), 38 Gy (38%), or 40 Gy (31%) was prescribed. Median volume percentage of CTV receiving at least 100% of prescription dose [V100% (%)] was 100% [interquartile range: 99.99-100]. Rectum V50% (%), V80% (%), and V90% (%) were significantly lower in patients who had spacer, with a mean difference of -9.70%, -6.59%, and -4.42%, respectively, compared to those who did not have spacer. Femoral head dose was lower with a 4-field arrangement. Mean differences in left and right femoral head V40% (%) were -6.99% and -10.74%, respectively.

Conclusion

We provide a large, novel report of patients treated with IMPT SABR for localized prostate cancer. Four-field IMPT with hydrogel spacer provides significant sparing of rectum and femoral heads without compromising target coverage.

High levels of health-related quality of life five years after curative treatment of prostate cancer with HDR-brachytherapy and external beam radiation

BACKGROUND AND PURPOSE

The aim of this cross-sectional study was to investigate long-term health-related quality of life (HRQoL) in men with prostate cancer treated 2002-2008 with external beam radiotherapy (EBRT) combined with high dose-rate brachytherapy (HDRBT), Cohort A, and to compare these data with age-adjusted normative data. In addition, differences in HRQoL following adjustments of the brachytherapy technique in 2001 were investigated by comparing Cohort A with men treated at the same clinic from 1998-2000, Cohort B.

METHODS AND MATERIAL

Cohort A: 1495 men treated with EBRT 2 Gy to 50 Gy and 2 fractions of 10 Gy HDRBT at a single centre, 2002-2008, still alive at five years. As part of routine follow-up, the patients responded to the EORTC QLQ-C30 and PR-25 questionnaires. Cohort B: HRQoL data was retrieved from an earlier study from the original article.

RESULTS

In Cohort A, 1046 (70%) men completed the questionnaires at five years, median age 66 years. In general, HRQoL mean scores were high and similar to Swedish age-matched normative data. Concerning disease-specific HRQoL, low levels of bowel and urinary problems were reported, in contrast to a substantial effect on sexual functioning. 'No' or 'A little' problems with faecal incontinence and urinary incontinence were reported by 98% and 93% of patients, respectively. The corresponding figure for sexual functioning was 39%. A difference in the frequency of nocturia in favour of Cohort A was the only statistically significant difference between Cohort A and B found in general and disease-specific HRQOL (p = 0.03), despite modifications in the brachytherapy procedure introduced in 2001.

CONCLUSION

Long-term general HRQoL was rated high and comparable to an aged-matched reference population five years after treatment with combined radiotherapy. Disease-specific HRQoL was still affected, foremost in the sexual domain.

Control of the activity of CAR-T cells within tumours via focused ultrasound

Focused ultrasound can deliver energy safely and non-invasively into tissues at depths of centimetres. Here we show that the genetics and cellular functions of chimeric antigen receptor T cells (CAR-T cells) within tumours can be reversibly controlled by the heat generated by short pulses of focused ultrasound via a CAR cassette under the control of a promoter for the heat-shock protein. In mice with subcutaneous tumours, locally injected T cells with the inducible CAR and activated via focused ultrasound guided by magnetic resonance imaging mitigated on-target off-tumour activity and enhanced the suppression of tumour growth, compared with the performance of non-inducible CAR-T cells. Acoustogenetic control of the activation of engineered T cells may facilitate the design of safer cell therapies.

Assessment of non-inferiority with meta-analysis: example of hypofractionated radiation therapy in breast and prostate cancer

The aim of this study was to propose a methodology for the assessment of non-inferiority with meta-analysis. Assessment of hypofractionated RT in prostate and breast cancers is used as an illustrative example. Non-inferiority assessment of an experimental treatment versus an active comparator should rely on two elements: (1) an estimation of experimental treatment’s effect versus the active comparator based on a meta-analysis of randomized controlled trials and (2) the value of an objective non-inferiority margin. This margin can be defined using the reported effect of active comparator and the percentage of the active comparator’s effect that is desired to be preserved. Non-inferiority can then be assessed by comparing the upper bound of the 95% confidence interval of experimental treatment’s effect to the value of the objective non-inferiority margin. Application to hypofractionated RT in breast cancer showed that hypofractionated whole breast irradiation (HWBI) appeared to be non-inferior to conventionally fractionated RT for local recurrence. This was not the case for accelerated partial breast irradiation (APBI). Concerning overall survival, non-inferiority could not be claimed for either HWBI or APBI. For prostate cancer, the lack of demonstrated significant superiority of conventional RT versus no RT precluded any conclusion regarding non-inferiority of hypofractionated RT.

Systemic Management for Nonmetastatic Castration-resistant Prostate Cancer: A Systematic Review and Network Meta-Analysis

PURPOSE

To indirectly compare the efficacy and safety of systemic therapies used for patients with nonmetastatic castration-resistant prostate cancer (nmCRPC).

METHODS

The relevant randomized controlled trials were retrieved from PubMed and the Cochrane Library. Network meta-analyses were used to compare multiple drugs simultaneously for the outcomes of nmCRPC. Direct evidence in trials and indirect evidence across trials were combined by the network meta-analyses to estimate the treatment efficiency.

OUTCOME

Eight studies were included in our research. For prostate-specific antigen progression-free survival, the rate of progression was significantly decreased following apalutamide, enzalutamide, bicalutamide+dutasteride, and bicalutamide treatment compared with placebo. Compared with placebo treatment, metastases-free survival was significantly increased in patients who received apalutamide (hazard ratio [HR]: 0.28, 95% confidence interval [CI]: 0.23-0.35), enzalutamide (HR: 0.29, 95% CI: 0.24-0.35), and darolutamide (HR: 0.42, 95% CI: 0.35-0.50). Direct comparison showed significant survival benefits in patients who received second-generation anti-androgen therapy (apalutamide, enzalutamide, and darolutamide: HR: 0.74, 95% CI: 0.61-0.91) compared with patients who received placebo. With respect to metastases-free survival, based on SUCRA analysis, there was 80% and 78% probability that apalutamide and enzalutamide were preferred treatment, while darolutamide was likely to be second-best choice. Compared with placebo, all agents were not associated with significantly higher likelihood of serious adverse events and grade 3 to 4 adverse events.

CONCLUSION

Our outcomes support equivalent efficacy and similar risk of adverse effects between apalutamide, enzalutamide, and darolutamide, supporting the use of these antiandrogen agents in high-risk of progression nmCRPC.

Cause of Mortality after Radical Prostatectomy and the Impact of Comorbidity in Men with Prostate Cancer: A Multi-institutional Study in Korea

Purpose

This study aimed to examine the causes of death in Korean patients who underwent radical prostatectomy for prostate cancer and investigate the relationship between comorbidity and mortality.

Materials and Methods

We conducted a retrospective multicenter cohort study including 4,064 consecutive patients who had prostate cancer and underwent radical prostatectomy between January 1998 and June 2013. The primary endpoint of this study was all-cause mortality, and the secondary endpoints were cancer-specific mortality (CSM) and other-cause mortality (OCM). Charlson comorbidity index (CCI) was calculated to assess the comorbidities of each patient.

Results

Of 4,064 patients, 446 (11.0%) died during follow-up. The cause of death was prostate cancer in 132 patients (29.6%), other cancers in 121 patients (27.1%), and vascular disease in 57 patients (12.8%) in our cohort. The overall 10-year CSM rate was lower than the OCM rate (4.6% vs. 10.5%). The 10-year CSM rate was lower than the OCM rate in low- to intermediate-risk group patients (1.2% vs. 10.6%), whereas they were similar in high-risk group patients (11.8% vs. 10.1%). In the multivariable analysis, CCI was independently associated with all-cause mortality after radical prostatectomy, regardless of age and pathologic features.

Conclusion

Death from prostate cancer was rare in Korean men who underwent radical prostatectomy. Clinicians should be aware of the possibility of overtreatment of low-risk prostate cancer in men with significant comorbidity. Our findings may help to facilitate counseling and plan management in this patient group.

Targeted biopsy of the prostate: does this result in improvement in detection of high-grade cancer or the occurrence of the Will Rogers phenomenon?

OBJECTIVE

To investigate whether patients with Gleason 3 + 4 cancer on transrectal biopsy are upgraded after undergoing transperineal magnetic resonance imaging (MRI)-targeted biopsy and whether this has implications for current clinical practice.

PATIENTS AND METHODS

In this retrospective analysis we examined 107 consecutive patients presenting at a single tertiary referral centre (July 2012 to July 2016) with prostate cancer of Gleason score 3 + 4 on transrectal ultrasonography (TRUS)-guided systematic non-targeted biopsy who then underwent a multiparametric MRI followed by MRI-targeted transperineal prostate biopsy for accurate risk stratification and localization.

RESULTS

The patients' mean (sd) age was 67.0 (8.0) years, and they had a median (interquartile range) PSA concentration of 6.2 (4.7-9.6) ng/mL. Of the 107 patients, 84 (78.5%) had Gleason 3 + 4 on both transrectal systematic biopsy and transperineal MRI-targeted biopsy. Nineteen patients (17.8%) were upgraded to Gleason 4 + 3, three patients (3.0%) to Gleason 4 + 4 and one patient (1.0%) to Gleason 4 + 5. These differences were significant (P = 0.0006). Likewise, 23/107 patients (22%) had higher-risk disease based on their targeted biopsies.

CONCLUSION

The use of targeted biopsy in men with impalpable cancer, ultimately upgraded one in five patients from favourable-intermediate- to unfavourable-intermediate-risk disease or worse. This has significant clinical implications for men considering active surveillance or radical treatment. Our risk calculators must now be validated using these data from targeted biopsy as the technique becomes widely adopted.

Randomized Trial of Hypofractionated, Dose-Escalated, Intensity-Modulated Radiation Therapy (IMRT) Versus Conventionally Fractionated IMRT for Localized Prostate Cancer

PURPOSE

Hypofractionated radiotherapy delivers larger daily doses of radiation and may increase the biologically effective dose delivered to the prostate. We conducted a randomized trial testing the hypothesis that dose-escalated, moderately hypofractionated intensity-modulated radiation therapy (HIMRT) improves prostate cancer control compared with conventionally fractionated IMRT (CIMRT) for men with localized prostate cancer.

PATIENTS AND METHODS

Men were randomly assigned to 75.6 Gy in 1.8-Gy fractions delivered over 8.4 weeks (CIMRT) or 72 Gy in 2.4 Gy fractions delivered over 6 weeks (HIMRT, biologically equivalent to 85 Gy in 1.8-Gy fractions assuming prostate cancer α-to-β ratio of 1.5). Failure was defined as prostate-specific antigen (PSA) failure (nadir plus 2 ng/mL) or initiation of salvage therapy. Modified Radiation Therapy Oncology Group criteria were used to grade late (≥ 90 days after completion of radiotherapy) GI and genitourinary toxicity.

RESULTS

Most of the 206 men (72%) had cT1, Gleason score 6 or 7 (99%), and PSA level ≤ 10 ng/mL (90%) disease. Androgen deprivation therapy was received by 24%. With a median follow-up of 8.5 years, men treated with HIMRT experienced fewer treatment failures (n = 10) than men treated with CIMRT (n = 21; P = .036). The 8-year failure rate was 10.7% (95% CI, 5.8% to 19.1%) with HIMRT and 15.4% (95% CI, 9.1% to 25.4%) with CIMRT. There was no difference in overall survival ( P = .39). There was a nonsignificant increase in late grade 2 or 3 GI toxicity with HIMRT (8-year 5.0% v 12.6%; P = .08). However, GI toxicity was only 8.6% when rectal volume receiving 65 Gy of HIMRT was ≤ 15%. Late genitourinary toxicity was similar ( P = .84). There was no grade 4 toxicity.

CONCLUSION

The results of this randomized trial demonstrate superior cancer control for men with localized prostate cancer who receive dose-escalated moderately hypofractionation radiotherapy while shortening treatment duration.

Trends in Treatment for Prostate Cancer in China: Preliminary Patterns of Care Study in a Single Institution

Objectives: A Patterns of Care Study (PCS) was performed in the largest regional medical center in Zhejiang Province, China. The hospital information system (HIS) was used to evaluate patient characteristics and changes in initial treatment patterns for prostate cancer and to determine recent predominant trends in treatment plans for prostate cancer (PCa) in China. Methods: Men who were newly diagnosed with localized or locally advanced PCa for 2010-2011 and 2016-2017 were identified in the HIS database. Patient characteristics and temporal trends in initial management were assessed, and differences between groups were evaluated for significance using Chi-square and Mann-Whitney U tests. Results: In total, 1792 patients met the study criteria, including 505 and 1287 patients in the 2010-2011 and 2016-2017 samples, respectively. The average age of patients diagnosed in the 2010-2011 PCS survey was 70 years, decreasing to 68 years when the 2016-2017 patients were included (P<0.001). In the 2010-2011 sample, 50.69% of the patients had an initial prostate-specific antigen (PSA) level ≥20 ng/ml. In contrast, the initial PSA level was 4-19.99 ng/ml for 66.67% of the patients in the 2016-2017 sample (P<0.001). Based on National Comprehensive Cancer Network (NCCN) criteria, the percentages of patients in low- and intermediate-risk groups increased from 33.06% to 54.78%; conversely, the percentages in high-risk, very high-risk, and regional (N1) groups decreased to a certain extent (P<0.001). According to European Association of Urology (EAU) criteria, the percentages of patients in low- and intermediate-risk groups increased from 32.07% to 53.69%, yet the percentage in the high-risk group decreased (P<0.001). The use of radical prostatectomy (RP) and radiation therapy (RT) increased from 48.32% to 76.46% and 5.35% to 16.94%, particularly in high-risk and low-risk groups, respectively, whereas the rates of hormone therapy (HT) and active surveillance and observation (AS&O) decreased from 32.28% to 4.27% and from 16.04% to 2.33%, respectively (P<0.001). A similar pattern was observed when patients were stratified by EAU risk group. Conclusions: The results of this real-world study in the largest regional medical center in Zhejiang Province, China, indicate that the predominant characteristics of PCa patients and trends in initial management are changing rapidly. We found the following: (a) a trend toward a decreased age among newly diagnosed patients; (b) a trend toward lower initial PSA levels; (c) a downward trend in risk group classification; (d) a significant increase in the likelihood of receiving RP, particularly in the high-risk group; (e) an increase in the rate of RP, mostly due to use of the Da Vinci robotic system; (f) a significant increase in the likelihood of receiving RT, especially in the low-risk group; and (g) a decrease in HT and AS&O.

Factors influencing prostate cancer patterns of care: An analysis of treatment variation using the SEER database

PURPOSE

The aim of this study is to describe the trends and factors that influence the initial treatment of men with localized prostate cancer (PC) in the United States between 2004 and 2014.

METHODS AND MATERIALS

The National Cancer Institute's Surveillance, Epidemiology and End Results database was used to identify patients with primary prostate adenocarcinoma between 2004 and 2014. Patients were staged in accordance with the American Joint Committee on Cancer 7th edition criteria and stratified according to the National Comprehensive Cancer Network guidelines risk group classification. Descriptive statistics describing treatment patterns by year of diagnosis, age, risk group, insurance status, and region were performed.

RESULTS

A total of 460,311 male patients were identified with sufficient information to be categorized into National Comprehensive Cancer Network risk groups. Overall, 30.9% of patients had low-risk disease, 38.1% were intermediate risk, 20.2% were high risk, 4.4% were very high risk, 1.6% were node-positive, and 4.7% had metastatic disease. During the study period, there was a 60% decrease in brachytherapy monotherapy utilization for patients with PC, and no definitive treatment increased from 20.3% in 2004 to 26.3% in 2014. There were regional treatment variations and discrepancies in treatment by age. Radical prostatectomy was performed on a greater proportion of insured patients than patients with Medicaid or those who were uninsured, but radiation therapy and no definitive treatment was administered to a greater proportion of uninsured and Medicaid patients.

CONCLUSIONS

PC treatment shows declining trends in brachytherapy utilization, increases in conservative management, and stability of surgical procedures over time. There is wide variation by geographical region, age, and insurance status.

Vasohibin-1 as a novel microenvironmental biomarker for patient risk reclassification in low-risk prostate cancer

Background

We previously reported high expression of vasohibin-1 (VASH1), which is specifically expressed in activated vascular endothelial cells, was a prognostic indicator of disease progression in prostate cancer. The aim of this study was to assess whether VASH1 expression at the area of normal prostatic tissue as well as that of intratumoral tissue could reflect the grade of malignancy of prostate cancer.

Results

Pathological upgrade of Gleason Score ≥7 by radical prostatectomy was observed in 48 patients (upgraded group). The median VASH1 densities of the intratumoral and normal areas were 9.7 ± 9.5 and 13.3 ± 11.8, respectively, and the median MVDs were 58.6 ± 20.3 and 64.1 ± 23.5, respectively. We detected a strong positive correlation with each other for both VASH1 density (ρ = 0.589, p < 0.001) and MVD (ρ = 0.342, p < 0.001). VASH1 density was significantly higher in the upgreaded group than in the non-upgraded group regardless of prostatic location (intratumoral area: p < 0.001, normal area: p < 0.001).

Conclusions

Even if the tumor volume was low in biopsy samples, VASH1 density reflected the grade of malignancy throughout the prostate. These results suggested that VASH1 expression could be a novel microenvironmental biomarker for patient risk reclassification in low-risk prostate cancer.

Materials and Methods

Among the 1177 patients who underwent radical prostatectomy, 104 patients diagnosed with Gleason Score ≤6 and positive cores ≤3 were included. We immunohistochemically examined the microvessels positive for anti-CD34 as microvessel density (MVD), and those with activated endothelial cells as VASH1 density using prostatic biopsy samples, and evaluated the association between their expressions and clinicopathological findings.

Post-prostatectomy radiation therapy for locally recurrent prostate cancer

INTRODUCTION

Approximately 15-30% of men with localized prostate cancer will experience biochemical recurrence (BCR) after radical prostatectomy. Postoperative radiation therapy is used in men with adverse pathological features to reduce the risk of BCR or with curative intent in men with known BCR. In this study, we review the evidence for the adjuvant and salvage radiation therapy after radical prostatectomy. Areas covered: A literature review of the Medline and Embase databases was performed. The search strategy included the following terms: prostate cancer, adjuvant radiotherapy, salvage radiotherapy, radical prostatectomy, biochemical recurrence, and prostate cancer recurrence. Prospective randomized trials for the adjuvant radiotherapy and observational studies supporting salvage radiotherapy were included for discussion. Expert commentary: As postoperative radiotherapy is associated with non-trivial risks of acute and long-term toxicity and given the absence of compelling data supporting adjuvant over early salvage radiotherapy, the authors advocate, with rare exceptions, close observation and timely (early) salvage radiotherapy for patients with BCR and long life expectancy. Adjuvant radiotherapy may be considered in patients at high-risk for recurrence. Observation is appropriate in patients with limited life expectancy and/or absence of adverse features.

Radiotherapy in prostate cancer treatment: results of the patterns of care study in Korea

Purpose

The purpose of this study was to describe treatment patterns of radiotherapy (RT) for prostate cancer in Korea.

Materials and Methods

A questionnaire about radiation treatment technique and principles in 2013 was sent to 83 radiation oncologists and data from 57 hospitals were collected analyzed to find patterns of RT for prostate cancer patients in Korea.

Results

The number of patients with prostate cancer treated with definitive RT ranged from 1 to 72 per hospital in 2013. RT doses and target volumes increased according to risk groups but the range of radiation doses was wide (60 to 81.4 Gy) and the fraction size was diverse (1.8 to 5 Gy). Intensity-modulated radiation therapy was used for definitive treatment in 93.8% of hospitals. Hormonal therapy was integrated with radiation for intermediate (63.2%) and high risk patients (77.2%). Adjuvant RT after radical prostatectomy was performed in 46 hospitals (80.7%). Indications of adjuvant RT included positive resection margin, seminal vesicle invasion, and capsular invasion. The total dose for adjuvant RT ranged from 50 to 72 Gy in 24–39 fractions. Salvage RT was delivered with findings of consecutive elevations in prostate-specific antigen (PSA), PSA level over 0.2 ng/mL, or clinical recurrence. The total radiation doses ranged from 50 to 80 Gy with a range of 1.8 to 2.5 Gy per fraction for salvage RT.

Conclusion

This nationwide patterns of care study suggests that variable radiation techniques and a diverse range of dose fractionation schemes are applied for prostate cancer treatment in Korea. Standard guidelines for RT in prostate cancer need to be developed.

Modern-day prostate cancer is not meaningfully associated with lower urinary tract symptoms: Analysis of a propensity score-matched cohort

INTRODUCTION

We sought to determine if prostate cancer (PCa) is associated with worse lower urinary tract symptoms (LUTS) than matched benign prostates, with attention to cancer characteristics, in a contemporary cohort.

METHODS

Using a single-institution database (January 1, 2009-June 30, 2013), men diagnosed with PCa on biopsy and controls with negative biopsies were matched 1:1 on age, prostate volume, and a propensity score predicting the probability of PCa diagnosis. International Prostate Symptom Score (IPSS) was compared between PCa cases and controls using paired statistics, stratifying on grade, cancer volume, stage, and D'Amico risk group. Sensitivity analyses were performed separately, repeating the match for high-grade, high-volume, and high-stage cancers only, and excluding users of benign prostatic hyperplasia medications.

RESULTS

In our cohort of 1330 men (665 with PCa), there were 284 (42.7%) Gleason 6 cancers (Grade Group 1), 315 (47.4%) Gleason 7 cancers (Grade Group 2-3), and 66 (9.9%) Gleason 8-10 cancers (Grade Group 4-5). There was no difference in IPSS between PCa cases (median 6.5, interquartile range [IQR] 3-12) and benign controls (median 7, IQR 3-13; p=0.34). Subgroup analyses based on cancer grade, volume, or stage, showed no significant differences in IPSS between men with and without PCa, except among men with cT2b-cT4 PC (median 9, IQR 5-16) vs. matched benign counterparts (median 8, IQR 3-12; p=0.03). Sensitivity analyses supported these findings.

CONCLUSIONS

Modern PCa does not appear to be associated with worse LUTS compared to benign prostates of the same size. Outlet obstruction is likely a late event in the natural history of PCa. This has implications for timely PCa detection, which should ideally be prior to the onset of LUTS.

A Monte Carlo study of I-125 prostate brachytherapy with gold nanoparticles: dose enhancement with simultaneous rectal dose sparing via radiation shielding

We investigate via Monte Carlo simulations a new ¹²⁵I brachytherapy treatment technique for high-risk prostate cancer patients via injection of Au nanoparticle (AuNP) directly into the prostate. The purpose of using the nanoparticles is to increase the therapeutic index via two synergistic effects: enhanced energy deposition within the prostate and simultaneous shielding of organs at risk from radiation escaping from the prostate. Both uniform and non-uniform concentrations of AuNP are studied. The latter are modeled considering the possibility of AuNP diffusion after the injection using brachy needles. We study two extreme cases of coaxial AuNP concentrations: centered on brachy needles and centered half-way between them. Assuming uniform distribution of 30 mg g^-1 of AuNP within the prostate, we obtain a dose enhancement larger than a factor of 2 to the prostate. Non-uniform concentration of AuNP ranging from 10 mg g^-1 and 66 mg g^-1 were studied. The higher the concentration in a given region of the prostate the greater is the enhancement therein. We obtain the highest dose enhancement when the brachytherapy needles are coincident with AuNP injection needles but, at the same time, the regions in the tail are colder (average dose ratio of 0.7). The best enhancement uniformity is obtained with the seeds in the tail of the AuNP distribution. In both uniform and non-uniform cases the urethra and rectum receive less than 1/3 dose compared to an analog treatment without AuNP. Remarkably, employing AuNP not only significantly increases dose to the target but also decreases dose to the neighboring rectum and even urethra, which is embedded within the prostate. These are mutually interdependent effects as more enhancement leads to more shielding and vice-versa. Caution must be paid since cold spot or hot spots may be created if the AuNP concentration versus seed position is not properly distributed respect to the seed locations.

The uptake of active surveillance for the management of prostate cancer: A population-based analysis

INTRODUCTION

Active surveillance (AS) is a strategy for the management of low-risk prostate cancer (PCa). However, few studies have assessed the uptake of AS at a population level and none of these were based on a Canadian population. Therefore, our objectives were to estimate the proportion of men being managed by AS in Ontario and to assess the factors associated with its uptake.

METHODS

This was a retrospective, population-based study using administrative databases from the province of Ontario to identify men ≤75 years diagnosed with localized PCa between 2002 and 2010. Descriptive statistics were used to estimate the proportion of men managed by AS, whereas mixed models were used to assess the factors associated with the uptake of AS.

RESULTS

45 691 men met our inclusion criteria. Of these, 18% were managed by AS. Over time, the rates of AS increased significantly from 11% to 21% (p<0.001). Older age, residing in an urban centre, being diagnosed in the later years of the study period, having a neighborhood income in the highest quintile, and being managed by urologists were all associated with greater odds of receiving AS.

CONCLUSIONS

There has been a steady increase in the uptake of AS between 2002 and 2010. However, only 18% of men diagnosed with localized PCa were managed by AS during the study period. The decisions to adopt AS were influenced by several individual and physician characteristics. The data suggest that there is significant opportunity for more widespread adoption of AS.

Patient-Level DNA Damage and Repair Pathway Profiles and Prognosis After Prostatectomy for High-Risk Prostate Cancer

IMPORTANCE

A substantial number of patients diagnosed with high-risk prostate cancer are at risk for metastatic progression after primary treatment. Better biomarkers are needed to identify patients at the highest risk to guide therapy intensification.

OBJECTIVE

To create a DNA damage and repair (DDR) pathway profiling method for use as a prognostic signature biomarker in high-risk prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

A cohort of 1090 patients with high-risk prostate cancer who underwent prostatectomy and were treated at 3 different academic institutions were divided into a training cohort (n = 545) and 3 pooled validation cohorts (n = 232, 130, and 183) assembled for case-control or case-cohort studies. Profiling of 9 DDR pathways using 17 gene sets for GSEA (Gene Set Enrichment Analysis) of high-density microarray gene expression data from formalin-fixed paraffin-embedded prostatectomy samples with median 10.3 years follow-up was performed. Prognostic signature development from DDR pathway profiles was studied, and DDR pathway gene mutation in published cohorts was analyzed.

MAIN OUTCOMES AND MEASURES

Biochemical recurrence-free, metastasis-free, and overall survival.

RESULTS

Across the training cohort and pooled validation cohorts, 1090 men were studied; mean (SD) age at diagnosis was 65.3 (6.4) years. We found that there are distinct clusters of DDR pathways within the cohort, and DDR pathway enrichment is only weakly correlated with clinical variables such as age (Spearman ρ [ρ], range, -0.07 to 0.24), Gleason score (ρ, range, 0.03 to 0.20), prostate-specific antigen level (ρ, range, -0.07 to 0.10), while 13 of 17 DDR gene sets are strongly correlated with androgen receptor pathway enrichment (ρ, range, 0.33 to 0.82). In published cohorts, DDR pathway genes are rarely mutated. A DDR pathway profile prognostic signature built in the training cohort was significantly associated with biochemical recurrence-free, metastasis-free, and overall survival in the pooled validation cohorts independent of standard clinicopathological variables. The prognostic performance of the signature for metastasis-free survival appears to be stronger in the younger patients (HR, 1.67; 95% CI, 1.12-2.50) than in the older patients (HR, 0.77; 95% CI, 0.29-2.07) on multivariate Cox analysis.

CONCLUSIONS AND RELEVANCE

DNA damage and repair pathway profiling revealed patient-level variations and the DDR pathways are rarely affected by mutation. A DDR pathway signature showed strong prognostic performance with the long-term outcomes of metastasis-free and overall survival that may be useful for risk stratification of high-risk prostate cancer patients.

The role of radical prostatectomy as an initial approach for the treatment of high-risk prostate cancer

CONTEXT

The treatment of high-risk prostate cancer requires a multimodal approach to improve control of the disease. There is still no consensus as to the initial strategy of choice. The aim of this study is to review the results of radical prostatectomy as first step in management of patients with high-risk disease.

ACQUISITION OF EVIDENCE

A search was conducted on PubMed of English and Spanish texts. We included those studies that reported the results of radical prostatectomy in patients with high-risk prostate cancer, as well as those that compared radical prostatectomy with other treatment alternatives. The last search was conducted in November 2015.

SYNTHESIS OF THE EVIDENCE

The advantages of radical prostatectomy include a better pathological analysis, more accurate staging, better local control of the disease and better follow-up and adjuvant therapy strategies. When compared with external radiation therapy plus hormonal blockade, the patients who underwent prostatectomy had greater chances of healing and longer cancer-specific survival. The patients who most benefit from this approach are younger, have fewer comorbidities and no evidence of organ metastases.

CONCLUSIONS

The available scientific evidence to date is not without bias and confounders; however, they appear to favour radical prostatectomy as the initial approach of choice for high-risk prostate cancer.

Prostate Cancer Registries: Current Status and Future Directions

CONTEXT

Disease-specific registries that enroll a considerable number of patients play a major role in prostate cancer (PCa) research.

OBJECTIVE

To evaluate available registries, describe their strengths and limitations, and discuss the potential future role of PCa registries in outcomes research.

EVIDENCE ACQUISITION

We performed a literature review of the Medline, Embase, and Web of Science databases. The search strategy included the terms prostate cancer, outcomes, statistical approaches, population-based cohorts, registries of outcomes, and epidemiological studies, alone or in combination. We limited our search to studies published between January 2005 and January 2015.

EVIDENCE SYNTHESIS

Several population-based and prospective disease-specific registries are currently available for prostate cancer. Studies performed using these data sources provide important information on incidence and mortality, disease characteristics at presentation, risk factors, trends in utilization of health care services, disparities in access to treatment, quality of care, long-term oncologic and health-related quality of life outcomes, and costs associated with management of the disease. Although data from these registries have some limitations, statistical methods are available that can address certain biases and increase the internal and external validity of such analyses. In the future, improvements in data quality, collection of tissue samples, and the availability of data feedback to health care providers will increase the relevance of studies built on population-based and disease-specific registries.

CONCLUSIONS

The strengths and limitations of PCa registries should be carefully considered when planning studies using these databases. Although randomized controlled trials still provide the highest level of evidence, large registries play an important and growing role in advancing PCa research and care.

PATIENT SUMMARY

Several population-based and prospective disease-specific registries for prostate cancer are currently available. Analyses of data from these registries yield information that is clinically relevant for the management of patients with prostate cancer.

Gaps between Evidence and Practice in Postoperative Radiotherapy for Prostate Cancer: Focus on Toxicities and the Effects on Health-Related Quality of Life

Adjuvant radiotherapy (ART) after prostatectomy for patients with high-risk features [extracapsular extension (ECE), seminal vesicle invasion (SVI), and positive margin] has been shown to be associated with improved biochemical disease-free survival in three large randomized trials and with improved overall survival in one. Similarly, salvage radiotherapy (SRT) can effectively achieve biochemical control in a significant proportion of patients with a rising PSA after surgery. Nonetheless, both approaches of postoperative RT remain highly underutilized. This might be partly due to concerns with overtreatment inherent to adjuvant approaches, and/or hesitance about causing radiation toxicities and their subsequent effects on the patient's quality of life. Herein, we review the literature lending evidence to these arguments. We show recent series of ART/SRT and their low rates of acute and long-term toxicities, translating only in transient decline in quality-of-life (QoL) outcomes. We conclude that concerns with side effects should not preclude the recommendation of an effective and curative-intent therapy for men with prostate cancer initially treated with radical surgery.

Applying precision medicine to the active surveillance of prostate cancer

The recent introduction of a variety of molecular tests will potentially reshape the care of patients with prostate cancer. These tests may make more accurate management decisions possible for those patients who have been "overdiagnosed" with biologically indolent disease, which represents an exceptionally small mortality risk. There is a wide range of possible applications of these tests to different clinical scenarios in patient populations managed with active surveillance. Cancer 2015;121:3435-43. © 2015 American Cancer Society.

A population-based analysis of contemporary patterns of care in younger men (<60 years old) with localized prostate cancer

PURPOSE

To analyze patterns of care in younger patients (<60 years old) with localized prostate cancer and to identify factors associated with selection of therapy using a large, population-based database.

METHODS

The Surveillance, Epidemiology, and End Results database was queried to identify men <60 years old diagnosed with localized prostate cancer between 2010 and 2011. Patients were determined to have undergone no active treatment, local therapy, radiation therapy (RT), or radical prostatectomy (RP). Univariate and multivariate logistic regression analyses were performed to identify factors associated with the use of definitive therapy.

RESULTS

A total of 12,732 men were included in this analysis. For the entire cohort, 12.5 % received no definitive treatment, 61.6 % RP, 22.0 % RT, and 3.3 % RP with adjuvant RT. Among men with low-, intermediate-, and high-risk prostate cancer, 17.2, 7.1, and 15.9 %, respectively, received no definitive therapy. RP was the most common choice of definitive therapy, utilized in 74.6 % of patients. Adjuvant RT after RP was utilized in 16.2 % of cases with positive margin and/or pT3/pT4 disease. African-American race, single marital status, and Medicaid/no insurance were associated with a decreased likelihood of receiving definitive treatment.

CONCLUSIONS

A significant proportion of younger men diagnosed with localized prostate cancer, particularly with low- or high-risk disease, are not receiving definitive therapy. African-American men, uninsured men, and patients with Medicaid or no medical insurance are less likely to receive definitive treatment.

Identifying the Most Informative Prediction Tool for Cancer-specific Mortality After Radical Prostatectomy: Comparative Analysis of Three Commonly Used Preoperative Prediction Models

BACKGROUND

The D'Amico risk stratification, Cancer of the Prostate Risk Assessment (CAPRA) score, and Stephenson nomogram are widely used prediction tools for biochemical recurrence and survival after radical prostatectomy (RP). These models have not been compared with respect to cancer-specific mortality (CSM) prediction.

OBJECTIVE

To validate and compare the prediction tools for 10-yr CSM.

DESIGN, SETTING, AND PARTICIPANTS

Overall, 2485 prostate cancer patients underwent RP in a European tertiary care center.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Three preoperative models (D'Amico, CAPRA, and Stephenson) were compared in terms of their ability to predict 10-yr CSM; therefore, accuracy tests (area under the receiver operating characteristic curve [AUC]), calibration plots, and decision curve analysis (DCA) were assessed for each model.

RESULTS AND LIMITATIONS

CSM at 10 yr was 3.6%. The AUC was 0.76, 0.77, and 0.80 for the D'Amico, CAPRA, and Stephenson models, respectively. In calibration plots, predicted probabilities were close to the observed probabilities for the D'Amico model but showed underestimation of CSM for the Stephenson nomogram and overestimation of CSM for the CAPRA score. DCA identified a benefit for the CAPRA score. These results apply to patients treated at a European tertiary care center.

CONCLUSIONS

Despite good discriminatory power, all tested models had some shortcomings in terms of prediction of 10-yr CSM. All three models showed good performance in North American cohorts, but our results suggested a lack of generalizability to European patients. To overcome this issue, local recalibration of the variable weights could be performed. Another possibility is the development of more universal markers that are independent of regional practice differences or, alternatively, the development of better tools to quantify clinical practice differences.

PATIENT SUMMARY

Prediction tools can predict cancer survival prior surgery, relying on points for age, prostate-specific antigen levels, aggressiveness, and percentage of cancer at biopsy. These tools are reliable in North American patients but have shortcomings for identifying patients at high risk of prostate cancer death in Europe.

Radiotherapy before and after radical prostatectomy for high-risk and locally advanced prostate cancer

OBJECTIVES

Men with localized high-risk prostate cancer carry significant risk of prostate cancer-specific mortality. The best treatment approach to minimize this risk is unclear. In this review, we evaluate the role of radiation before and after radical prostatectomy.

METHODS AND MATERIALS

A critical review of the literature was performed regarding the application of external radiation therapy (RT) in combination with prostatectomy for high-risk localized prostate cancer.

RESULTS

Up to 70% of men with high-risk localized disease may require adjuvant therapy because of adverse pathologic features or biochemical recurrence in the absence of systemic disease. The utility of adjuvant RT among men with adverse pathologic features are well established at least regarding minimizing biochemical recurrence risk. The optimal timing of salvage radiation is the subject of ongoing studies. Neoadjuvant RT requires further study but is a potentially attractive method because of decreased radiation field sizes and potential radiobiologic benefits of delivering RT before surgery. Salvage prostatectomy is effective at treating local recurrence after radiation but is associated with significant surgical morbidity.

CONCLUSIONS

Combining local therapies including radical prostatectomy and RT can be a reasonable approach. Care should be taken at the initial presentation of high-risk localized prostate cancer to consider and plan for the likelihood of multimodality care.