Androgen deprivation therapy does not impact cause-specific or overall survival in high-risk prostate cancer managed with brachytherapy and supplemental external beam

ACR-ABS-ASTRO Practice Parameter for Transperineal Permanent Brachytherapy of Prostate Cancer

AIM/OBJECTIVES/BACKGROUND

The American College of Radiology (ACR), American Brachytherapy Society (ABS), and American Society for Radiation Oncology (ASTRO) have jointly developed the following practice parameter for transperineal permanent brachytherapy of prostate cancer. Transperineal permanent brachytherapy of prostate cancer is the interstitial implantation of low-dose rate radioactive seeds into the prostate gland for the purpose of treating localized prostate cancer.

METHODS

This practice parameter was developed according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website (https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters-Radiation Oncology of the Commission on Radiation Oncology, in collaboration with ABS and ASTRO.

RESULTS

This practice parameter provides a framework for the appropriate use of low-dose rate brachytherapy in the treatment of prostate cancer either as monotherapy or as part of a treatment regimen combined with external-beam radiation therapy. The practice parameter defines the qualifications and responsibilities of all involved radiation oncology personnel, including the radiation oncologist, medical physicist, dosimetrist, radiation therapist, and nursing staff. Patient selection criteria and the utilization of supplemental therapies such as external-beam radiation therapy and androgen deprivation therapy are discussed. The logistics of the implant procedure, postimplant dosimetry assessment, and best practices with regard to safety and quality control are presented.

CONCLUSIONS

Adherence to established standards can help to ensure that permanent prostate brachytherapy is delivered in a safe and efficacious manner.

Brachytherapy Combined With or Without Hormone Therapy for Localized Prostate Cancer: A Meta-Analysis and Systematic Review

Purpose: The purpose of this study was to evaluate the efficacy of brachytherapy combined with or without hormone therapy in patients with localized prostate cancer.

Methods and Materials: We systemically searched the Medline, Web of Science, Cochrane Library and Embase databases for studies published between the databases' dates of inception and February 2019. The primary endpoints were the 5-year overall survival (OS) rates, 5-year biochemical progression-free survival (bPFS) rates and 10-year bPFS rates. The results were expressed as the relative risk (RR) and 95% confidence interval (CI). Based on the heterogeneity evaluated with the I² statistic, a meta-analysis was performed using either a random- or fixed-effects model.

Results: A total of 16 cohort studies including 9,359 patients met all the criteria for inclusion in the analysis. Our data showed that brachytherapy (BT) combined with hormone therapy (HT) increased the patients' 5-year bPFS rates (RR = 1.04, 95% CI: 1.01–1.08, P = 0.005) and 10-year bPFS rates (RR = 1.12, 95% CI: 1.02–1.23, P = 0.001) compared with BT monotherapy. However, BT combined with HT did not increase the patients' 5-year OS rates (RR = 1.02, 95% CI: 0.99–1.095, P = 0.1) compared with BT monotherapy.

Conclusions: BT combined with HT can increase the bPFS rates of patients with localized prostate cancer, but it does not improve patients' OS rates.

Biochemical outcomes and predictive factors by risk group after permanent iodine-125 seed implantation: Prospective cohort study in 2,316 patients

PURPOSE

To evaluate the biochemical freedom from failure (bFFF) by risk group and treatment modality and the predictive factors of bFFF by risk group in patients with prostate cancer undergoing permanent seed implantation (PI) with or without external beam radiation therapy (EBRT) in a nationwide prospective cohort study (Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 [I-125] Seed Implantation) in Japan during the first 2 years.

METHODS AND MATERIALS

The analyses included 2,316 participants in 42 institutions; bFFF was evaluated using the Phoenix definition and calculated using the Kaplan-Meier method, and the Cox proportional hazards model was used to identify the factors associated with bFFF.

RESULTS

Median followup period was 60.0 months. The 5-year bFFF rates in all patients, 1,028 low-risk patients, 1,114 intermediate-risk patients, and 133 high-risk patients were 93.6%, 94.9%, 92.7%, and 91.1%, respectively. The 5-year bFFF rates in the PI group and EBRT combination therapy group were 93.7% and 93.3%, respectively. In a multivariate analysis, younger age, higher Gleason score (GS), higher percent positive biopsies (%PB), and lower prostate V₁₀₀ (p = 0.0012, 0.0030, 0.0026, and 0.0368) in all patients; younger age, higher pretreatment prostate-specific antigen, and lower prostate V₁₀₀ (p = 0.0002, 0.0048, and 0.0012) in low-risk patients; higher GS, higher %PB, and no hormonal treatment (p = 0.0005, 0.0120, and 0.0022) in intermediate-risk patients; and higher GS and higher %PB (p = 0.0329 and 0.0120) in high-risk patients were significantly associated with bFFF.

CONCLUSIONS

PI with or without EBRT resulted in excellent short-term biochemical outcomes in all risk groups, especially in high-risk patients. Age, pretreatment prostate-specific antigen, and prostate V₁₀₀ in low-risk patients; GS, %PB, and hormonal treatment in intermediate-risk patients; and GS and %PB in high-risk patients were independently affected bFFF.

Practice patterns of primary EBRT with and without ADT in prostate cancer treatment

BACKGROUND

Androgen deprivation therapy (ADT) has been shown to improve survival for men with intermediate and high-risk prostate cancer undergoing external-beam radiation therapy (EBRT). Using data from a community-based prospective disease registry, we investigated usage of EBRT with or without neoadjuvant ADT.

METHODS

The CaPSURE database contains 14,863 men with prostate cancer, including 1337 men diagnosed between 1990 and 2014 with localized disease who received EBRT as primary treatment. Prostate cancer risk was calculated using the CAPRA score. Patient characteristics were compared using the Mantel-Haenszel chi-square test for trend and analysis of variance.

RESULTS

Between 1990 and 2014, 14,010 men were diagnosed with localized disease within the CaPSURE registry. Of those, 1337 underwent EBRT. Patients had a median age of 71 years. The use of ADT in addition to EBRT increased from 24% in 1990 to 60% in 1996 with a decrease seen to 47% in 2011. Men receiving ADT have differing clinical characteristics including higher PSA at diagnosis, higher Gleason grade, and higher CAPRA scores. Median ADT duration was 4 months.

CONCLUSIONS

The use of ADT in conjunction with primary EBRT has increased in frequency and duration since 1990. Men receiving ADT have higher risk characteristics than those receiving EBRT alone. There is substantial variability in use of ADT in clinical practice.

The evolution of brachytherapy for prostate cancer

Brachytherapy (BT), using low-dose-rate (LDR) permanent seed implantation or high-dose-rate (HDR) temporary source implantation, is an acceptable treatment option for select patients with prostate cancer of any risk group. The benefits of HDR-BT over LDR-BT include the ability to use the same source for other cancers, lower operator dependence, and - typically - fewer acute irritative symptoms. By contrast, the benefits of LDR-BT include more favourable scheduling logistics, lower initial capital equipment costs, no need for a shielded room, completion in a single implant, and more robust data from clinical trials. Prospective reports comparing HDR-BT and LDR-BT to each other or to other treatment options (such as external beam radiotherapy (EBRT) or surgery) suggest similar outcomes. The 5-year freedom from biochemical failure rates for patients with low-risk, intermediate-risk, and high-risk disease are >85%, 69-97%, and 63-80%, respectively. Brachytherapy with EBRT (versus brachytherapy alone) is an appropriate approach in select patients with intermediate-risk and high-risk disease. The 10-year rates of overall survival, distant metastasis, and cancer-specific mortality are >85%, <10%, and <5%, respectively. Grade 3-4 toxicities associated with HDR-BT and LDR-BT are rare, at <4% in most series, and quality of life is improved in patients who receive brachytherapy compared with those who undergo surgery.

American Brachytherapy Society Task Group Report: Use of androgen deprivation therapy with prostate brachytherapy-A systematic literature review

PURPOSE

Prostate brachytherapy (PB) has well-documented excellent long-term outcomes in all risk groups. There are significant uncertainties regarding the role of androgen deprivation therapy (ADT) with brachytherapy. The purpose of this report was to review systemically the published literature and summarize present knowledge regarding the impact of ADT on biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS).

METHODS AND MATERIALS

A literature search was conducted in Medline and Embase covering the years 1996-2016. Selected were articles with >100 patients, minimum followup 3 years, defined risk stratification, and directly examining the role and impact of ADT on bPFS, CSS, and OS. The studies were grouped to reflect disease risk stratification. We also reviewed the impact of ADT on OS, cardiovascular morbidity, mortality, and on-going brachytherapy randomized controlled trials (RCTs).

RESULTS

Fifty-two selected studies (43,303 patients) were included in this review; 7 high-dose rate and 45 low-dose rate; 25 studies were multi-institutional and 27 single institution (retrospective review or prospective data collection) and 2 were RCTs. The studies were heterogeneous in patient population, risk categories, risk factors, followup time, and treatment administered, including ADT administration and duration (median, 3-12 months);71% of the studies reported a lack of benefit, whereas 28% showed improvement in bPFS with addition of ADT to PB. The lack of benefit was seen in low-risk and favorable intermediate-risk (IR) disease and most high-dose rate studies. A bPFS benefit of up to 15% was seen with ADT use in patients with suboptimal dosimetry, those with multiple adverse risk factors (unfavorable IR [uIR]), and most high-risk (HR) studies. Four studies reported very small benefit to CSS (2%). None of the studies showed OS advantage; however, three studies reported an absolute 5-20% OS detriment with ADT. Literature suggests that OS detriment is more likely in older patients or those with pre-existing cardiovascular disease. Four RCTs with an adequate number of patients and well-defined risk stratification are in progress. One RCT will answer the question regarding the role of ADT with PB in favorable IR patients and the other three RCTs will focus on optimal duration of ADT in the uIR and favorable HR population.

CONCLUSIONS

Patients treated with brachytherapy have excellent long-term disease outcomes. Existing evidence shows no benefit of adding ADT to PB in low-risk and favorable IR patients. UIR and HR patients and those with suboptimal dosimetry may have up to 15% improvement in bPFS with addition of 3-12 months of ADT, with uncertain impact on CSS and a potential detriment on OS. To minimize morbidity, one should exercise caution in prescribing ADT together with PB, in particular to older men and those with existing cardiovascular disease. Due to the retrospective nature of this evidence, significant selection, and treatment bias, no definitive conclusions are possible. RCT is urgently needed to define the potential role and optimal duration of ADT in uIR and favorable HR disease.

Results of multiparametric transrectal ultrasound-based focal high-dose-rate dose escalation combined with supplementary external beam irradiation in intermediate- and high-risk localized prostate cancer patients

PURPOSE

Clinical results of a biologic information-based focused dose escalation combined with dose de-escalation for the whole organ in external beam radiotherapy + high-dose-rate brachytherapy (HDR-BT) boost application for localized prostate cancer in a consecutively treated patient cohort.

METHODS AND MATERIALS

One hundred thirty patients were treated with external beam radiotherapy (50 Gy) complementary to two multiparametric transrectal ultrasound-guided 15 Gy HDR-BT fractions. Real-time multiparametric transrectal ultrasound-based biologic planning for high-dose-rate boost dose planning used the summation of gray scale and Doppler sonography imaging + biopsy information. Target subvolumes received HDR-BT dose escalation up to 60 Gy/fraction. Dose-volume histogram parameters, organ at risks doses, and toxicity results were investigated.

RESULTS

The median followup was 4.3 years, the median age was 68.62 years, and the mean initial prostate-specific antigen was 18.69 ng/mL. Low-, intermediate-, and high-risk constituted 69%, 21%, and 10% of the patients, respectively. The mean peripheral dose was 3.9 Gy per fraction. Prostate-specific antigen nadir was in 93% of the patients ≤1 ng/mL. Quality parameters were as follows: D₉₀: 6.58 Gy, V₁₀₀: 30.36%, V₁₅₀: 9.96%, V₂₀₀: 3.16%, uD_0.1: 7.34 Gy, uD₂: 9.34 Gy, rD₀₁: 10.56 Gy, and rD₂: 8.32 Gy, respectively. We observed G1, G2, G3 urinary toxicity in 17/130, 11/130, and 2/130 patients, respectively. Rectal toxicity: G1 and G2 occurred in 19/130 and 2/130 patients with mean dose values G1: 8.2 Gy and G2: 8.76 Gy. Analysis of variance test resulted in no correlation between toxicities and any other investigated factors.

CONCLUSIONS

Focused extreme dose escalation with low prostate mean peripheral dose results in excellent long-term outcome data and very high focal boost doses and is causing no enhancement in late treatment toxicity.

Androgen deprivation therapy is associated with diabetes: Evidence from meta-analysis

Aims/Introduction

There is still no obvious evidence proving that androgen deprivation therapy (ADT) would increase the risk of diabetes. To determine if ADT is associated with diabetes in men with prostate cancer, we carried out the present study.

Materials and Methods

We systematically searched Medline, Embase and the Cochrane Library Central Register through 2014. Studies comparing ADT vs control aimed at treating prostate cancer reporting diabetes as outcome were included. Data were extracted independently by two reviewers. This meta‐analysis was reported based on the Preferred Reporting Items for Systematic reviews and Meta‐Analyses checklist. Observational studies were evaluated through the Meta‐analysis Of Observational Studies in Epidemiology checklist.

Results

Eight studies were identified with 65,695 ADT users and 91,893 non‐ADT users. The pooled incidence of diabetes was 39% higher in ADT groups. A significant association was observed in the overall analysis (risk ratio [RR] 1.39, 95% confidence interval [CI] 1.27–1.53; P < 0.001). In subgroup analyses, diabetes was found to be significantly associated with gonadotropin‐releasing hormone (GnRH) alone (RR 1.45, 95% CI 1.36–1.54; P < 0.001), GnRH plus oral antiandrogen (RR 1.40, 95% CI 1.01–1.93; P = 0.04) and orchiectomy (RR 1.34, 95% CI 1.20–1.50; P < 0.001), but not with antiandrogen alone (RR 1.33, 95% CI 0.75–2.36; P = 0.33). Diabetes was strongly related to long duration of ADT (RR 1.43, 95% CI 1.22–1.68; P < 0.001), and was slightly associated with short duration of ADT (RR 1.29, 95% CI 1.12–1.49; P = 0.0004).

Conclusions

ADT, especially long duration (>6 months) of this treatment, GnRH alone, GnRH plus antiandrogen and orchiectomy can increase the incidence of diabetes.

Combined brachytherapy and external beam radiotherapy without adjuvant androgen deprivation therapy for high-risk prostate cancer

Background

To report the outcomes of patients treated with combined iodine-125 (I-125) brachytherapy and external beam radiotherapy (EBRT) for high-risk prostate cancer.

Methods

Between 2003 and 2009, I-125 permanent prostate brachytherapy plus EBRT was performed for 206 patients with high-risk prostate cancer. High-risk patients had prostate-specific antigen ≥ 20 ng/mL, and/or Gleason score ≥ 8, and/or Stage ≥ T3. One hundred and one patients (49.0%) received neoadjuvant androgen deprivation therapy (ADT) but none were given adjuvant ADT. Biochemical failure-free survival (BFFS) was determined using the Phoenix definition.

Results

The 5-year actuarial BFFS rate was 84.8%. The 5-year cause-specific survival and overall survival rates were 98.7% and 97.6%, respectively. There were 8 deaths (3.9%), of which 2 were due to prostate cancer. On multivariate analysis, positive biopsy core rates and the number of high-risk factors were independent predictors of BFFS. The 5-year BFFS rates for patients in the positive biopsy core rate <50% and ≥50% groups were 89.3% and 78.2%, respectively (p = 0.03). The 5-year BFFS rate for patients with the any single high-risk factor was 86.1%, compared with 73.6% for those with any 2 or all 3 high-risk factors (p = 0.03). Neoadjuvant ADT did not impact the 5-year BFFS.

Conclusions

At a median follow-up of 60 months, high-risk prostate cancer patients undergoing combined I-125 brachytherapy and EBRT without adjuvant ADT have a high probability of achieving 5-year BFFS.

Tri-Modality therapy with I-125 brachytherapy, external beam radiation therapy, and short- or long-term hormone therapy for high-risk localized prostate cancer (TRIP): study protocol for a phase III, multicenter, randomized, controlled trial

Background

Patients with high Gleason score, elevated prostate specific antigen (PSA) level, and advanced clinical stage are at increased risk for both local and systemic relapse. Recent data suggests higher radiation doses decrease local recurrence and may ultimately benefit biochemical, metastasis-free and disease-specific survival. No randomized data is available on the benefits of long-term hormonal therapy (HT) in these patients. A prospective study on the efficacy and safety of trimodality treatment consisting of HT, external beam radiation therapy (EBRT), and brachytherapy (BT) for high-risk prostate cancer (PCa) is strongly required.

Methods/Design

This is a phase III, multicenter, randomized controlled trial (RCT) of trimodality with BT, EBRT, and HT for high-risk PCa (TRIP) that will investigate the impact of adjuvant HT following BT using iodine-125 (¹²⁵I-BT) and supplemental EBRT with neoadjuvant and concurrent HT. Prior to the end of September 2012, a total of 340 patients with high-risk PCa will be enrolled and randomized to one of two treatment arms. These patients will be recruited from more than 41 institutions, all of which have broad experience with ¹²⁵I-BT. Pathological slides will be centrally reviewed to confirm patient eligibility. The patients will commonly undergo 6-month HT with combined androgen blockade (CAB) before and during ¹²⁵I-BT and supplemental EBRT. Those randomly assigned to the long-term HT group will subsequently undergo 2 years of adjuvant HT with luteinizing hormone-releasing hormone agonist. All participants will be assessed at baseline and every 3 months for the first 30 months, then every 6 months until 84 months from the beginning of CAB.

The primary endpoint is biochemical progression-free survival. Secondary endpoints are overall survival, clinical progression-free survival, disease-specific survival, salvage therapy non-adaptive interval, and adverse events.

Discussion

To our knowledge, there have been no prospective studies documenting the efficacy and safety of trimodality therapy for high-risk PCa. The present RCT is expected to provide additional insight regarding the potency and limitations of the addition of 2 years of adjuvant HT to this trimodality approach, and to establish an appropriate treatment strategy for high-risk PCa.

Trial registration

UMIN000003992

Risk stratification in the hormonal treatment of patients with prostate cancer

Prostate cancer (PCa) is the most common type of cancer found in American men, other than skin cancer. The American Cancer Society estimates that there will be 186,320 new cases of prostate cancer in the United States in 2008. About 28,660 men will die of this disease this year and PCa remains the second-leading cause of cancer death in men. One in six men will get PCa during his lifetime and one in 35 will die of the disease. Today, more than 2 million men in the United States who have had PCa are still alive. The death rate for PCa continues to decline, chiefly due to early detection and treatment, and improved salvage therapy such as hormone therapy (HT). HT continues to be a mainstay for primary-recurrent PCa and locally-advanced PCa. However, HT is associated with many undesirable side effects including sexual dysfunction, osteoporosis and hot flashes, all of which can lead to decreased quality of life (QOL). These risks are seen in both long- and short-term HT regimens. Additionally, research in recent years has revealed trends related to clinico pathological variables and their predictive ability in HT outcomes. Awareness of the potential adverse effects, the risks associated with HT and the prognostic ability of clinical and pathological variables is important in determining optimal therapy for individual patients. A rigorous evaluation of the current scientific literature associated with HT was conducted with the goal of identifying the most favorable balance of benefits and risks associated with HT.

Higher percentage of positive biopsy cores and Gleason score are associated with a greater degree of prostate gland shrinkage after neoadjuvant cytoreductive therapy

PURPOSE

To determine whether adverse pathologic features, including tumor grade and percent positive biopsy (PPB) cores, predict for prostate size reduction after neoadjuvant cytoreductive therapy.

METHODS AND MATERIALS

Eighty-two consecutive patients who were diagnosed with prostate cancer by transperineal template-guided mapping biopsy (TTMB) received neoadjuvant cytoreductive therapy. The median number of biopsy cores was 59. Thirty patients received a leutinizing hormone-releasing hormone agonist and bicalutamide, whereas 52 patients received bicalutamide (50mg daily) and dutasteride (0.5mg daily). A transrectal ultrasound volumetric study of the prostate gland and ellipsoid volume determinations of the prostate gland and transition zone (TZ) were obtained immediately before TTMB and at 90 days (±7 days) after the initiation of neoadjuvant medical therapy. Univariate and multivariate regression analyses were performed to identify predictors of prostate gland and TZ volume reduction.

RESULTS

At TTMB, the mean prostate volumetric and ellipsoid volumes were 55.4 cm(3) and 49.0 cm(3), respectively. After neoadjuvant medical therapy, the mean volumetric and ellipsoid prostate volumes were 30.8 cm(3) and 28.5 cm(3), respectively. On average, the prostate volume decreased by 43.9% and 41.0% on volumetric and ellipsoid measurements, respectively. The TZ volume decreased from 19.8 cm(3) to 10.1 cm(3) (mean volume reduction of 47.7%). In multivariate analysis, prostate volume cytoreduction was most closely associated with PPB (p=0.014), TTMB prostate volume (p=0.01), and drug regimen (p=0.001).

CONCLUSIONS

The degree of prostate volume cytoreduction was positively associated with higher Gleason score and PPBs. Greater reductions in prostate volume may be an indicator of more aggressive cancer.

Low-dose rate brachytherapy for men with localized prostate cancer

BACKGROUND

Localized prostate cancer is a slow growing tumor for many years for the majority of affected men. Low-dose rate brachytherapy (LDR-BT) is short-distance radiotherapy using low-energy radioactive sources. LDR-BT has been recommended for men with low risk localized prostate cancer.

OBJECTIVES

To assess the benefit and harm of LDR-BT compared to radical prostatectomy (RP), external beam radiotherapy (EBRT), and no primary therapy (NPT) in men with localized prostatic cancer.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 1950), and EMBASE (from 1980) were searched in June 2010 as well as online trials registers and reference lists of reviews.

SELECTION CRITERIA

Randomized, controlled trials comparing LDR-BT versus RP, EBRT, and NPT in men with clinically localized prostate cancer.

DATA COLLECTION AND ANALYSIS

Data on study methods, participants, treatment regimens, observation period and outcomes were recorded by two reviewers independently.

MAIN RESULTS

We identified only one RCT (N = 200; mean follow up 68 months). This trial compared LDR-BT and RP. The risk of bias was deemed high. Primary outcomes (overall survival, cause-specific mortality, or metastatic-free survival) were not reported. Biochemical recurrence-free survival at 5 years follow up was not significantly different between LDR-BT (78/85 (91.8%)) and RP (81/89 (91.0%)); P = 0.875; relative risk 0.92 (95% CI: 0.35 to 2.42).For severe adverse events reported at 6 months follow up, results favored LDR-BT for urinary incontinence (LDR-BT 0/85 (0.0%) versus RP 16/89 (18.0%); P < 0.001; relative risk 0) and favored RP for urinary irritation (LDR-BT 68/85 (80.0%) versus RP 4/89 (4.5%); P < 0.001; relative risk 17.80, 95% CI 6.79 to 46.66). The occurrence of urinary stricture did not significantly differ between the treatment groups (LDR-BT 2/85 (2.4%) versus RP 6/89 (6.7%); P = 0.221; relative risk 0.35, 95% CI: 0.07 to 1.68). Long-term information was not available.We did not identify significant differences of mean scores between treatment groups for patient-reported outcomes function and bother as well as generic health-related quality of life.

AUTHORS' CONCLUSIONS

Low-dose rate brachytherapy did not reduce biochemical recurrence-free survival versus radical prostatectomy at 5 years. For short-term severe adverse events, low-dose rate brachytherapy was significantly more favorable for urinary incontinence, but radical prostatectomy was significantly more favorable for urinary irritation. Evidence is based on one RCT with high risk of bias.

Androgen deprivation therapy and definitive radiotherapy for prostate cancer

Adjuvant androgen deprivation therapy (ADT) improves outcomes of patients receiving definitive radiotherapy (RT) for local-regionally advanced prostate cancer. However, patients in most randomized trials had more advanced disease than observed in many practices and were treated with suboptimal RT doses. Although data are conflicting, long-term ADT likely has adverse side-effects in patients with comorbidities. We recommend 6 months of ADT monotherapy with gonadotropin-releasing hormone agonist and RT for patients with high-risk prostate cancer (≥T2c, Gleason Score 8 to 10, and/or prostate-specific antigen ≥20 ng/mL) with minimal or no comorbidities. Adjuvant ADT for unfavorable intermediate-risk patients with a Gleason Score of 4+3=7 is also reasonable.

Predictors of the use of supplemental androgen suppression therapy and external beam radiation in men with high-risk prostate cancer undergoing brachytherapy in community practice

PURPOSE

We assessed clinical- and practice-related variables associated with the use of trimodality treatment (androgen suppression therapy, external beam radiation therapy, and brachytherapy) in a community-based cohort of men with high-risk prostate cancer.

METHODS AND MATERIALS

The study cohort was composed of 1342 men with a prostate-specific antigen level >20ng/mL, clinical tumor stage T3 or T4, and/or Gleason score 8-10 disease at two community radiation facilities, Chicago Prostate Cancer Center (Chicago PCC) and 21st Century Oncology (21C). Logistic regression multivariable analysis was performed to identify factors associated with trimodality treatment.

RESULTS

Of 1342 men treated from 1991 to 2005, 650 (48%) received trimodality therapy. Factors associated with trimodality use include younger age (adjusted odds ratio [AOR] 0.95, p<0.0001), increasing prostate-specific antigen (AOR 1.54, p<0.0001), Gleason score 7 (AOR 2.88, p<0.0001), Gleason score 8-10 (AOR 4.28, p<0.0001), clinical category T2 (AOR 1.40, p=0.012), clinical category T3 (AOR 4.84, p<0.0001), and year of brachytherapy (AOR 1.13, p<0.0001). Patients treated at 21C were 4.6 times more likely to receive trimodality therapy (p<0.0001) than Chicago PCC. There was a significant interaction between cardiovascular comorbidity status and site (comorbidity×21C, AOR 1.74, p=0.025), indicating that less healthy patients were more likely to receive trimodality treatment at 21C than healthy patients and vice versa at Chicago PCC.

CONCLUSIONS

Younger men and those with more aggressive pretreatment clinical factors were more likely to receive trimodality treatment in this community cohort of men with high-risk prostate cancer. Selection for trimodality use varied significantly by site indicating a need for treatment standardization in the community.

Relationship between prostate cancer mortality and number of unfavourable risk factors in men treated with definitive brachytherapy

OBJECTIVE

To explore whether the number of unfavourable pretreatment risk factors predicts cause-specific mortality in men treated with prostate brachytherapy.

PATIENTS AND METHODS

Between April 1995 and March 2006, 739 patients were treated who had at least one of the following adverse risk factors: pretreatment prostate-specific antigen (PSA) level of >10 ng/mL, a Gleason score of > or =7, clinical stage > or =T2b, or a PSA velocity (PSAV) of >2 ng/mL/year. Supplemental external beam radiotherapy (EBRT) was delivered to 464 (62.8%) men and 301 (40.7%) received androgen deprivation therapy (ADT). Of men with more than two risk factors, 87% received EBRT and 62% received ADT.

RESULTS

The biochemical progression-free survival (bPFS), cause-specific survival (CSS) and overall survival for all patients were 95.0%, 97.9% and 70.0% at 12 years. Men with three or four risk factors had a prostate cancer-specific mortality (PCSM) at 12 years of 5.3%, vs 1.7% for men with one or two risk factors (P= 0.006). When 'percentage of positive biopsy cores >50%' replaced PSAV as a risk factor, men with two or more risk factors had a PCSM of 8.9%, vs 1.0% for men with one or two risk factors (P= 0.001). There was no difference in all-cause mortality between the groups in either analysis.

CONCLUSION

Multimodal brachytherapy results in high rates of bPFS and CSS, even for men with several unfavourable risk factors. Men with two or more unfavourable risk factors had a slightly greater risk of PCSM and no difference in all-cause mortality. The presence of three or four unfavourable intermediate-risk factors does not appear to clearly identify a group that requires further treatment intensification, although the percentage of positive cores might be more predictive than PSAV.

Brachytherapy for prostate cancer: a systematic review

Low-dose rate brachytherapy has become a mainstream treatment option for men diagnosed with prostate cancer because of excellent long-term treatment outcomes in low-, intermediate-, and high-risk patients. To a great extend due to patient lead advocacy for minimally invasive treatment options, high-quality prostate implants have become widely available in the US, Europe, and Japan. High-dose-rate (HDR) afterloading brachytherapy in the management of localised prostate cancer has practical, physical, and biological advantages over low-dose-rate seed brachytherapy. There are no free live sources used, no risk of source loss, and since the implant is a temporary procedure following discharge no issues with regard to radioprotection use of existing facilities exist. Patients with localized prostate cancer may benefit from high-dose-rate brachytherapy, which may be used alone in certain circumstances or in combination with external-beam radiotherapy in other settings. The purpose of this paper is to present the essentials of brachytherapies techniques along with the most important studies that support their effectiveness in the treatment of prostate cancer.

Risk of Death From Prostate Cancer After Brachytherapy Alone or With Radiation, Androgen Suppression Therapy, or Both in Men With High-Risk Disease

Purpose

We estimated the risk of prostate cancer (PC) –specific mortality (PCSM) after brachytherapy alone or in conjunction with androgen suppression therapy (AST), external-beam radiation therapy (EBRT), or both in men with high-risk PC.

Patients and Methods

The study cohort comprised 1,342 men with a prostate-specific antigen level more than 20 ng/mL and clinical T3 or 4 and/or Gleason score 8 to 10 disease. Competing risks multivariable regression was performed to estimate the risk of PCSM in men treated with brachytherapy alone or with supplemental AST, EBRT, or both, adjusting for age, year of treatment, and known PC prognostic factors.

Results

Despite higher baseline probabilities of PCSM after a median follow-up of 5.1 years, there was a significant reduction in the risk of PCSM (adjusted hazard ratio [AHR], 0.32; 95% CI, 0.14 to 0.73; P = .006) in men treated with brachytherapy and both AST and EBRT as compared with neither. When compared with brachytherapy alone, a significant decrease in the risk of PCSM was not observed in men treated with either supplemental AST (AHR, 0.63; 95% CI, 0.27 to 1.47; P = .28) or EBRT (AHR, 0.57; 95% CI, 0.21 to 1.52; P = .26). There was a near-significant reduction (AHR, 0.53; 95% CI, 0.27 to 1.07; P = .079) in the risk of PCSM in men treated with tri- as compared with bimodality therapy.

Conclusion

Supplemental AST and EBRT but not either supplement compared with brachytherapy alone was associated with a decreased risk of PCSM in men with high-risk PC.

Outcomes for patients with high-grade prostate cancer treated with a combination of brachytherapy, external beam radiotherapy and hormonal therapy

OBJECTIVE

To assess the outcomes for patients with Gleason score 8-10 prostate cancer treated with brachytherapy, external beam radiotherapy (EBRT) and hormonal therapy (HT).

PATIENTS AND METHODS

In all, 181 patients with Gleason scores 8-10 prostate cancer were treated from 1994 to 2006 with a (103)Pd implant (prescription dose 100 Gy), 45 Gy of EBRT and 9 months of HT. The median (range) follow-up was 65 (24-150) months; freedom from biochemical failure (FBF) rates were calculated using the Phoenix definition.

RESULTS

The 8-year actuarial FBF, freedom from distant metastases, prostate-cancer specific survival and overall survival were 73%, 80%, 87% and 79%, respectively. The pretreatment prostate-specific antigen (PSA) level significantly affected FBF, with 8-year rates of 72%, 82% and 58% for patients with PSA level of <or=10, >10-20 and >20 ng/mL, respectively (P = 0.006). The PSA level had no significant effect on rates of distant metastases. The Gleason score had the most significant affect on FBF in a multivariate analysis, and was the only factor to significantly affect rates of distant metastases; the 8-year FBF rates were 84%, 55% and 30% for scores of 8, 9 and 10, respectively (P = 0.003). The corresponding freedom from distant metastases and prostate-cancer specific survival rates were 86%, 76%, 30% (P < 0.001) and 92%, 80%, 62.5% (P = 0.003), respectively.

CONCLUSIONS

The 8-year outcomes after this regimen showed favourable biochemical and distant control, as well disease-specific survival rates for patients with Gleason scores of 8-10. This treatment approach should be considered as a viable option for this subset of patients with high-risk disease.

Definitive radiotherapy for prostate cancer

The probability of extraprostatic disease may be estimated based on clinical T-stage, pretreatment prostatic-specific antigen, Gleason score, and percent positive core biopsies. Patients with disease confined to the prostate may be treated with either prostatectomy or radiotherapy (RT). Patients with extraprostatic disease without evidence of distant metastases are best managed with RT. RT consisting of either external beam and/or brachytherapy results in a relatively high likelihood of cure, particularly for those with low- and intermediate-risk disease. The impact of elective nodal RT on survival is unclear. Dose escalation results in improved biochemical relapse-free survival compared with standard dose RT. Androgen deprivation therapy likely improves the probability of disease control in patients with high-risk cancers.

Prostate cancer control and survival in Vietnam veterans exposed to Agent Orange

BACKGROUND

In this study, we evaluated the impact of Agent Orange exposure on survival in Vietnam Veterans undergoing prostate brachytherapy.

METHODS AND MATERIAL

From May 1995 to January 2005, 81 Vietnam veterans (29 with Agent Orange exposure and 52 without) and 433 nonveterans of comparable age (mean age, 58 years) underwent prostate brachytherapy. The mean follow-up was 5.0 years. Biochemical progression-free survival (bPFS) was defined as a prostate-specific antigen (PSA)< or =0.40ng/mL after nadir. Patients with metastatic prostate cancer or hormone refractory disease without obvious metastases who died of any cause were classified as died of prostate cancer. All other deaths were attributed to the immediate cause of death. Multiple parameters were evaluated for impact on survival.

RESULTS

At 9 years, Agent Orange-exposed men were least likely to remain biochemically controlled (89.5%, 100%, and 97.2% in Agent Orange-exposed, nonexposed veterans, and nonveterans, respectively, p=0.012). No significant differences in cause-specific (CSS) (p=0.832) or overall survival (OS) (p=0.363) were discerned. In multivariate analysis, CSS was best predicted by Gleason Score and day 0 D(90), whereas Gleason Score, % positive biopsies, and D(90) predicted for bPFS. None of the evaluated parameters predicted for OS, however, a trend was identified for better OS in younger patients and those with a higher D(90). In addition, Agent Orange exposure did not predict for any of the survival parameters. To date, 22 patients have died (metastatic prostate cancer two, second malignancies nine, cardiovascular disease eight, trauma two, and pulmonary one).

CONCLUSIONS

In this cohort of prostate brachytherapy patients, Agent Orange exposure did not statistically impact survival in multivariate analysis.

What is the role of androgen deprivation therapy in the treatment of locally advanced prostate cancer?

This Practice Point commentary discusses the paper by Horwitz and colleagues, which reported the long-term results of the RTOG 92-02 trial in which patients with locally advanced, node-negative prostate cancer who were treated with neoadjuvant-concurrent hormone ablation therapy and external beam radiation therapy (70 Gy) were subsequently randomized to receive either no further androgen deprivation or long-term (2-year) goserelin therapy. The results at 10 years confirm biochemical and clinical outcome benefits with the use of long-term androgen deprivation therapy for patients treated with conventional-dose radiotherapy. How these results should best be incorporated into dose-escalated radiotherapeutic approaches remains unclear, however, and this issue requires further investigation.

Primary causes of death after permanent prostate brachytherapy

PURPOSE

To evaluate the primary causes of death in low-risk (low-risk), intermediate-risk (intermediate-risk), and high-risk (high-risk) patients undergoing permanent prostate brachytherapy with or without supplemental therapies.

METHODS AND MATERIALS

From April 1995 through November 2004, a total of 1,354 consecutive patients underwent prostate brachytherapy. All patients underwent brachytherapy >3 years before analysis. Of the patients, 532 (39.3%) received androgen deprivation therapy and 703 (51.9%) received supplemental radiation therapy. The median follow-up was 5.4 years. Multiple parameters were evaluated as predictors of cause-specific, biochemical progression-free, and overall survival.

RESULTS

The 10-year cause-specific survival was 97.0% (99.7%, 99.0%, and 90.1% for low-risk, intermediate-risk, and high-risk patients). Overall survival was 76.7% (82.5%, 78.3%, and 67.6% for low-, intermediate-, and high-risk patients, respectively). The cumulative death rate for cardiovascular disease was 11.5% (8.7%, 9.3%, and 19.8% for low-, intermediate-, and high-risk patients). The death rate from second malignancies (nonprostate cancer) was 7.2% and was not substantially different when stratified by risk group. Death from all other causes was 6.5% for the entire cohort but 1.3%, 5.0%, and 10.8% for low-, intermediate-, and high-risk patients. In multivariate analysis, death from prostate cancer was best predicted by Gleason score and risk group, whereas death from cardiovascular disease, nonprostate cancer, and all other causes were most closely related to patient age and tobacco use.

CONCLUSIONS

Although cardiovascular mortality was the predominant cause of death, prostate cancer was responsible for approximately 10% of all deaths. In particular, overall survival was poorest in the high-risk group. Although high-risk patients were most likely to die of prostate cancer, the divergence in overall survival between high-risk and lower-risk patients primarily resulted from an excess of cardiovascular deaths. Changes in lifestyle to improve cardiovascular health may improve overall survival in patients with clinically localized prostate cancer.

Prostate brachytherapy in men > or =75 years of age

PURPOSE

To evaluate cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in prostate cancer patients aged > or =75 years undergoing brachytherapy with or without supplemental therapies.

METHODS AND MATERIALS

Between April 1995 and August 2004, 145 consecutive patients aged > or =75 years underwent permanent prostate brachytherapy. Median follow-up was 5.8 years. Biochemical progression-free survival was defined by a prostate-specific antigen level < or =0.40 ng/mL after nadir. Patients with metastatic prostate cancer or hormone-refractory disease without obvious metastases who died of any cause were classified as dead of prostate cancer. All other deaths were attributed to the immediate cause of death. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on survival.

RESULTS

Nine-year CSS, bPFS, and OS rates for the entire cohort were 99.3%, 97.1%, and 64.5%, respectively. None of the evaluated parameters predicted for CSS, whereas bPFS was most closely predicted by percentage positive biopsies. Overall survival and non-cancer deaths were best predicted by tobacco status. Thirty-seven patients have died, with 83.8% of the deaths due to cardiovascular disease (22 patients) or second malignancies (9 patients). To date, only 1 patient (0.7%) has died of metastatic prostate cancer.

CONCLUSIONS

After brachytherapy, high rates of CSS and bPFS are noted in elderly prostate cancer patients. Overall, approximately 65% of patients are alive at 9 years, with survival most closely related to tobacco status. We believe our results support an aggressive locoregional approach in appropriately selected elderly patients.