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Metastatic prostate cancer remains lethal with a 5-year survival rate of about 30%, indicating the need for better treatment options. Novel antiandrogens (NAA)—enzalutamide and abiraterone—have been the mainstay of treatment for advanced disease since 2011. In patients who progress on the first NAA, responses to the second NAA are infrequent (25–30%) and short-lasting (median PFS ~3 months). With the growing adoption of NAA therapy in pre-metastatic castration-resistant settings, finding better treatment options for first-line mCRPC has become an urgent clinical need. The regulatory approval of two PARP inhibitors in 2020—rucaparib and olaparib—has provided the first targeted therapy option for patients harboring defects in selected DNA damage response and repair (DDR) pathway genes. However, a growing body of preclinical and clinical data shows that co-inhibition of AR and PARP induces synthetic lethality and could be a promising therapy for patients without any DDR alterations. In this review article, we will investigate the limitations of NAA monotherapy, the mechanistic rationale for synthetic lethality induced by co-inhibition of AR and PARP, the clinical data that have led to the global development of a number of these AR and PARP combination therapies, and how this may impact patient care in the next 2–10 years.

SpaceOAR, a Food and Drug Administration-approved hydrogel intended to create a rectal-prostate space, was evaluated in a single-blind phase III trial of image guided intensity modulated radiation therapy. A total of 222 men were randomized 2:1 to the spacer or control group and received 79.2 Gy in 1.8-Gy fractions to the prostate with or without the seminal vesicles. The present study reports the final results with a median follow-up period of 3 years.Cumulative (Common Terminology Criteria for Adverse Events, version 4.0) toxicity was evaluated using the log-rank test. Quality of life (QOL) was examined using the Expanded Prostate Cancer Index Composite (EPIC), and the mean changes from baseline in the EPIC domains were tested using repeated measures models. The proportions of men with minimally important differences (MIDs) in each domain were tested using repeated measures logistic models with prespecified thresholds.The 3-year incidence of grade ≥1 (9.2% vs 2.0%; P=.028) and grade ≥2 (5.7% vs 0%; P=.012) rectal toxicity favored the spacer arm. Grade ≥1 urinary incontinence was also lower in the spacer arm (15% vs 4%; P=.046), with no difference in grade ≥2 urinary toxicity (7% vs 7%; P=0.7). From 6 months onward, bowel QOL consistently favored the spacer group (P=.002), with the difference at 3 years (5.8 points; P.05) meeting the threshold for a MID. The control group had a 3.9-point greater decline in urinary QOL compared with the spacer group at 3 years (P.05), but the difference did not meet the MID threshold. At 3 years, more men in the control group than in the spacer group had experienced a MID decline in bowel QOL (41% vs 14%; P=.002) and urinary QOL (30% vs 17%; P=.04). Furthermore, the control group were also more likely to have experienced large declines (twice the MID) in bowel QOL (21% vs 5%; P=.02) and urinary QOL (23% vs 8%; P=.02).The benefit of a hydrogel spacer in reducing the rectal dose, toxicity, and QOL declines after image guided intensity modulated radiation therapy for prostate cancer was maintained or increased with a longer follow-up period, providing stronger evidence for the benefit of hydrogel spacer use in prostate radiation therapy.

Purpose We sought to develop a quality surveillance program for approximately 15,000 US veterans treated at the 40 radiation oncology facilities at the Veterans Affairs (VA) hospitals each year. Methods and Materials State-of-the-art technologies were used with the goal to improve clinical outcomes while providing the best possible care to veterans. To measure quality of care and service rendered to veterans, the Veterans Health Administration established the VA Radiation Oncology Quality Surveillance program. The program carries forward the American College of Radiology Quality Research in Radiation Oncology project methodology of assessing the wide variation in practice pattern and quality of care in radiation therapy by developing clinical quality measures (QM) used as quality indices. These QM data provide feedback to physicians by identifying areas for improvement in the process of care and identifying the adoption of evidence-based recommendations for radiation therapy. Results Disease-site expert panels organized by the American Society for Radiation Oncology (ASTRO) defined quality measures and established scoring criteria for prostate cancer (intermediate and high risk), non-small cell lung cancer (IIIA/B stage), and small cell lung cancer (limited stage) case presentations. Data elements for 1567 patients from the 40 VA radiation oncology practices were abstracted from the electronic medical records and treatment management and planning systems. Overall, the 1567 assessed cases passed 82.4% of all QM. Pass rates for QM for the 773 lung and 794 prostate cases were 78.0% and 87.2%, respectively. Marked variations, however, were noted in the pass rates for QM when tumor site, clinical pathway, or performing centers were separately examined. Conclusions The peer-review protected VA-Radiation Oncology Surveillance program based on clinical quality measures allows providers to compare their clinical practice to peers and to make meaningful adjustments in their personal patterns of care unobtrusively.

We applied an established prognostic model to high-risk prostate cancer (HRPC) patients treated with radiotherapy (RT) and evaluated the influence of clinical and treatment variables on treatment outcomes.In total, 1075 HRPC patients undergoing definitive radiotherapy (RT) between 1995 and 2010 were retrospectively reviewed. Median follow-up was 62.3 months. Patients received either dose-escalated external beam radiotherapy (n=628, EBRT) or combined-modality radiotherapy (n=447, pelvic RT and low-dose rate brachytherapy boost, CMRT). 82.9% received androgen-deprivation therapy (ADT). A prognostic model stratified patients into predefined groups (good, intermediate, and poor). Kaplan-Meier methods and Cox proportional hazards regressions assessed biochemical failure (BF), distant metastasis (DM), prostate cancer-specific mortality (PCSM) and overall mortality (OM). C-indices analyzed predictive value.The model was prognostic; C-indices for BF, DM, PCSM and OM were: 0.62, 0.64, 0.61, and 0.57. On multivariate analysis, CMRT and longer ADT (≥24 mo) were associated with improved BF, DM, and PCSM. Gleason score (GS) 9-10 was the strongest predictor of PCSM. C-indices for BF, DM, PCSM, and OM using a 4-compartment model incorporating GS 9-10 were: 0.62, 0.65, 0.68, and 0.56. In poor-prognosis patients (GS 8-10+additional risk factors), CMRT+LTADT (12 mo) had 10-year PCSM (3.7%±3.6%), comparing favorably to 25.8%±9.2% with EBRT+LTADT.The model applies to high-risk RT patients; GS 9-10 remains a powerful predictor of PCSM. Comparing similar prognosis patients, CMRT is associated with improved disease-specific outcomes relative to EBRT. In poor-prognosis patients, CMRT+LTADT yields superior 10-year PCSM, potentially improving RT treatment personalization for those with HRPC.

214 Background: Multiple authorities including an NCI Taskforce have recommended routine evaluation of patient reported outcomes (PRO) in cancer care. The Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC-CP) is a single-page quality-of-life (QOL) tool which is easily integrated into routine clinical practice. The EPIC-CP has 5 domains (each scored 0-12). The present study evaluated whether early clinically significant changes in EPIC-CP were correlated with later changes in patients undergoing definitive radiotherapy (RT) for prostate cancer. Methods: A cohort of 979 patients including the PROSTQA study and 3 other institutions with prospective QOL data pooled for analysis were evaluated for patient-reported outcomes. Patients were treated with definitive low-dose rate brachytherapy (n=284), intensity-modulated RT (n=251), or stereotactic body RT (n=444). EPIC-CP scores were derived based upon responses to the EPIC-26. Data were evaluated using minimal clinically important difference (MCID) thresholds to compare QOL at 1-2 months and 24 months from baseline. Univariate analysis was used to assess the correlation between early and late MCID changes. Results: On univariate analysis, early ≥1 MCID change from baseline was strongly associated with a late ≥1 MCID across all 5 domains (urinary incontinence, urinary irritation/obstruction, bowel, sexual, and vitality/hormonal) within EPIC-CP and for the overall EPIC-CP score (Table). When MCID was instead defined as 1 or 3, early toxicity remained predictive of late toxicity for all domains and the overall EPIC-CP score. Conclusions: The EPIC-CP is an easy-to-use QOL assessment with clinically relevant outcomes. Early QOL decline was strongly associated with late QOL decline in patients undergoing definitive RT for prostate cancer across all EPIC-CP domains. Patients with early QOL decline may be candidates for early QOL-based interventions to alleviate their late toxicity burden from treatment. [Table: see text]

BACKGROUND Stereotactic body radiation therapy (SBRT) for localized prostate cancer involves high-dose-per-fraction radiation treatments. Its use is increasing, but concerns remain about treatment-related toxicity. The authors assessed the incidence and predictors of a global decline in health-related quality of life (HRQOL) after prostate SBRT. METHODS From 2008 to 2014, 713 consecutive men with localized prostate cancer received treatment with SBRT according to a prospective institutional protocol. Expanded Prostate Cancer Index Composite (EPIC-26) HRQOL data were collected at baseline and longitudinally for 5 years. EPIC-26 is comprised of 5 domains. The primary endpoint was defined as a decline exceeding the clinically detectable threshold in ≥4 EPIC-26 domains, termed multidomain decline. RESULTS The median age was 69 years, 46% of patients had unfavorable intermediate-risk or high-risk disease, and 20% received androgen-deprivation therapy. During 1 to 3 months and 6 to 60 months after SBRT, 8% to 15% and 10% to 11% of patients had multidomain declines, respectively. On multivariable analysis, lower baseline bowel HRQOL (odds ratio, 1.8; 95% confidence interval, 1.2-2.7; P < .01) and baseline depression (odds ratio, 5.7; 95% confidence interval, 1.3-24.3; P = .02) independently predicted for multidomain decline. Only 3% to 4% of patients had long-term multidomain declines exceeding twice the clinical threshold, and 30% of such declines appeared to be related to prostate cancer treatment or progression of disease. CONCLUSIONS Prostate SBRT has minimal long-term impact on multidomain decline, and the majority of more significant multidomain declines appear to be unrelated to treatment. This emphasizes the importance of focusing not only on the side effects of prostate cancer treatment but also on other comorbid illnesses that contribute to overall HRQOL. Cancer 2017;123:1635-1642. © 2017 American Cancer Society.

Purpose To determine whether a dose-response relationship exists for salvage radiation therapy (RT) of biochemical failure after prostatectomy for prostate cancer. Methods and Materials Individual data from 1108 patients who underwent salvage RT at 10 academic centers were pooled. The cohort was enriched for selection criteria more likely associated with tumor recurrence in the prostate bed (margin positive and pre-RT prostate-specific antigen [PSA] level of ≤2.0 ng/mL) and without the confounding of planned androgen suppression. The cumulative incidence of biochemical failure and distant metastasis over time was computed, and competing risks hazard regression models were used to investigate the association between potential predictors and these outcomes. The association of radiation dose with outcomes was the primary focus. Results With a 65.2-month follow-up duration, the 5- and 10-year estimates of freedom from post-RT biochemical failure (PSA level >0.2 ng/mL and rising) was 63.5% and 49.8%, respectively, and the cumulative incidence of distant metastasis was 12.4% by 10 years. A Gleason score of ≥7, higher pre-RT PSA level, extraprostatic tumor extension, and seminal vesicle invasion were associated with worse biochemical failure and distant metastasis outcomes. A salvage radiation dose of ≥66.0 Gy was associated with a reduced cumulative incidence of biochemical failure, but not of distant metastasis. Conclusions The use of salvage radiation doses of ≥66.0 Gy are supported by evidence presented in the present multicenter pooled analysis of individual patient data. The observational reporting method, limited sample size, few distant metastasis events, modest follow-up duration, and elective use of salvage therapy might have diminished the opportunity to identify an association between the radiation dose and this endpoint.

Purpose The new short Expanded Prostate Cancer Index Composite for Clinical Practice (EPIC-CP) patient-reported health-related quality of life (HRQOL) tool has removed the rectal bleeding question from the previous much longer version, EPIC-26. Herein, we assess the impact of losing the dedicated rectal bleeding question in 2 independent prospective multicenter cohorts. Methods and Materials In a prospective multicenter test cohort (n=865), EPIC-26 patient-reported HRQOL data were collected for 2 years after treatment from patients treated with prostate radiation therapy from 2003 to 2011. A second prospective multicenter cohort (n=442) was used for independent validation. A repeated-effects model was used to predict the change from baseline in bowel summary scores from longer EPIC instruments using the change in EPIC-CP bowel summary scores with and without rectal bleeding scores. Results Two years after radiation therapy, 91% of patients were free of bleeding, and only 2.6% reported bothersome bleeding problems. Correlations between EPIC-26 and EPIC-CP bowel scores were very high ( r 2 =0.90-0.96) and were statistically improved with the addition of rectal bleeding information ( r 2 =0.94-0.98). Considering all patients, only 0.2% of patients in the test cohort and 0.7% in the validation cohort reported bothersome bleeding and had clinically relevant HRQOL changes missed with EPIC-CP. However, of the 2.6% (n=17) of men with bothersome rectal bleeding in the test cohort, EPIC-CP failed to capture 1 patient (6%) as experiencing meaningful declines in bowel HRQOL. Conclusions Modern prostate radiation therapy results in exceptionally low rates of bothersome rectal bleeding, and

Purpose We aimed to update a previously published, multi-institutional nomogram of outcomes for salvage radiotherapy (SRT) following radical prostatectomy (RP) for prostate cancer, including patients treated in the contemporary era. Methods Individual data from node-negative patients with a detectable post-RP prostate-specific antigen (PSA) treated with SRT with or without concurrent androgen-deprivation therapy (ADT) were obtained from 10 academic institutions. Freedom from biochemical failure (FFBF) and distant metastases (DM) rates were estimated, and predictive nomograms were generated. Results Overall, 2,460 patients with a median follow-up of 5 years were included; 599 patients (24%) had a Gleason score (GS) ≤ 6, 1,387 (56%) had a GS of 7, 244 (10%) had a GS of 8, and 230 (9%) had a GS of 9 to 10. There were 1,370 patients (56%) with extraprostatic extension (EPE), 452 (18%) with seminal vesicle invasion (SVI), 1,434 (58%) with positive surgical margins, and 390 (16%) who received ADT (median, 6 months). The median pre-SRT PSA was 0.5 ng/mL (interquartile range, 0.3 to 1.1). The 5-yr FFBF rate was 56% overall, 71% for those with a pre-SRT PSA level of 0.01 to 0.2 ng/mL (n = 441), 63% for those with a PSA of 0.21 to 0.50 ng/mL (n = 822), 54% for those with a PSA of 0.51 to 1.0 ng/mL (n = 533), 43% for those with a PSA of 1.01 to 2.0 ng/mL (n = 341), and 37% for those with a PSA > 2.0 ng/mL (n = 323); P < .001. On multivariable analysis, pre-SRT PSA, GS, EPE, SVI, surgical margins, ADT use, and SRT dose were associated with FFBF. Pre-SRT PSA, GS, SVI, surgical margins, and ADT use were associated with DM, whereas EPE and SRT dose were not. The nomogram concordance indices were 0.68 (FFBF) and 0.74 (DM). Conclusion Early SRT at low PSA levels after RP is associated with improved FFBF and DM rates. Contemporary nomograms can estimate individual patient outcomes after SRT in the modern era.

There has been a recent proposal to change the grading system of prostate cancer into a five-tier grade grouping system. The prognostic impact of this has been demonstrated in regards only to biochemical recurrence-free survival (bRFS) with short follow-up (3 years).Between 1990 and 2013, 847 consecutive men were treated with definitive external beam radiation therapy at a single academic center. To validate the new grade grouping system, bRFS, distant metastases-free survival (DMFS) and prostate cancer-specific survival (PCSS) were calculated. Adjusted Kaplan-Meier and multivariable Cox regression analyses were performed to assess the independent impact of the new grade grouping system. Discriminatory analyses were performed to compare the commonly used three-tier Gleason score system (6, 7 and 8-10) to the new system.The median follow-up of our cohort was 88 months. The 5-grade groups independently validated differing risks of bRFS (group 1 as reference; adjusted hazard ratio (aHR) 1.35, 2.16, 1.79 and 3.84 for groups 2-5, respectively). Furthermore, a clear stratification was demonstrated for DMFS (aHR 2.03, 3.18, 3.62 and 13.77 for groups 2-5, respectively) and PCSS (aHR 3.00, 5.32, 6.02 and 39.02 for groups 2-5, respectively). The 5-grade group system had improved prognostic discrimination for all end points compared with the commonly used three-tiered system (that is, Gleason score 6, 7 and 8-10).In a large independent radiotherapy cohort with long-term follow-up, we have validated the bRFS benefit of the proposed five-tier grade grouping system. Furthermore, we have demonstrated that the system is highly prognostic for DMFS and PCSS. Grade group 5 had markedly worse outcomes for all end points, and future work is necessary to improve outcomes in these patients.

Objectives The aim of this study was to report treatment outcomes in patients with very high-risk prostate cancer (VHRPC) treated with dose-escalated radiotherapy. Methods We conducted a retrospective multi-institutional review on patients with VHRPC (those with at least 2 high-risk factors of prostate-specific antigen >20 ng/mL, Gleason score 8 to 10, or clinical T3 to T4 stage), treated with either dose-escalated external-beam radiotherapy (EBRT) or combined-modality radiotherapy (CMRT) consisting of pelvic irradiation and permanent interstitial brachytherapy. Results A total of 238 patients with VHRPC were identified. Of them, 69% of patients received EBRT and 31% received CMRT; 88% received androgen-deprivation therapy (ADT), 56% for ≥24 months (long-term ADT). The majority (69%) of patients were above 65 years old and were less likely to receive CMRT than younger patients (25% vs. 43%, P=0.006), although they did not differ from younger patients in tumor characteristics. Median follow-up was 61 months (interquartile range, 38 to 93 mo). Biochemical progression-free survival (BPFS), distant metastasis-free survival (DMFS), and cancer-specific survival (CSS) for all patients at 8 years were (±SE): 50.6%±4.7%, 68.5%±4.3%, 78.7%±3.8%, respectively, and were similar for patients 65 years and below versus above 65 years old (BPFS: HR=0.88, P=0.56; DMFS: HR=0.79, P=0.40; CSS HR=0.99, P=0.99). After adjustment for patient, tumor, and treatment-related covariates on multivariate analysis, CMRT was associated with improved BPFS (HR=0.44, P=0.012) with trends for DMFS (HR=0.52, P=0.10) and CSS (HR=0.55, P=0.21), whereas long-term ADT was independently associated with improved BPFS (HR=0.40, P=0.019), CSS (HR=0.20, P=0.002), and PCSM (HR=0.25, P=0.004). Conclusions Dose-escalated EBRT or CMRT with long-term ADT resulted in favorable clinical outcomes for patients with VHRPC.

PURPOSE: Increased murine double minute 2 (MDM2) expression, independent of p53 status, is associated with increased cancer-specific mortality for men with prostate cancer treated with radiotherapy. We assessed MI-219, a small molecule inhibitor of MDM2 with improved pharmacokinetics over nutlin-3, for sensitization of prostate cancer cells to radiotherapy and androgen deprivation therapy, a standard treatment option for men with high-risk prostate cancer. EXPERIMENTAL DESIGN: The effect of MDM2 inhibition by MI-219 was assessed in vitro and in vivo with mouse xenograft models across multiple prostate cancer cell lines containing varying p53 functional status. RESULTS: MDM2 inhibition by MI-219 resulted in dose- and time-dependent p53 activation and decreased clonogenic cell survival after radiation in a p53-dependent manner. Mechanistically, radiosensitization following inhibition of MDM2 was largely the result of p53-dependent increases in apoptosis and DNA damage as evidenced by Annexin V flow cytometry and γ-H2AX foci immunofluorescence. Similarly, treatment with MI-219 enhanced response to antiandrogen therapy via a p53-dependent increase in apoptotic cell death. Lastly, triple therapy with radiation, androgen deprivation therapy, and MI-219 decreased xenograft tumor growth compared with any single- or double-agent treatment. CONCLUSION: MDM2 inhibition with MI-219 results in p53-dependent sensitization of prostate cancer cells to radiation, antiandrogen therapy, and the combination. These findings support MDM2 small molecule inhibitor therapy as a therapy intensification strategy to improve clinical outcomes in high-risk localized prostate cancer. TRANSLATIONAL RELEVANCE: The combination of radiotherapy and androgen deprivation therapy is a standard treatment option for men with high-risk prostate cancer. Despite improvements in outcomes when androgen deprivation therapy is added to radiation, men with high-risk prostate cancer have significant risk for disease recurrence, progression, and even death within the first 10 years following treatment. We demonstrate that treatment with MI-219 (an inhibitor of MDM2) results in prostate cancer cell sensitization to radiation and androgen deprivation therapy in vitro and in vivo . Triple therapy with MI-219, radiation, and androgen deprivation therapy dramatically decreased tumor growth compared with any single- or double-agent therapy. These findings provide evidence that inhibition of MDM2 is a viable means by which to enhance the efficacy of both radiation and androgen deprivation therapy and thereby improve outcomes in the treatment of prostate cancer. As such, further investigation is warranted to translate these findings to the clinical setting.

OBJECTIVES To assess the performance of the Cancer of the Prostate Risk Assessment (CAPRA) prognostic tool for freedom-from-metastases (FFM) and cause-specific survival (CSS) in patients with localized prostate cancer treated with definitive external beam radiotherapy (EBRT), and to determine whether the performance of CAPRA is influenced by androgen deprivation therapy (ADT) use or the presence of Gleason pattern 5 (GP-5). MATERIALS AND METHODS A total of 612 patients from a prospective database of 718 patients treated with dose-escalated EBRT from 1998 to 2008 who met CAPRA scoring criteria were included in the study. Performance of CAPRA and association of CAPRA score, GP-5 and short-term or long-term ADT use (STAD or LTAD, respectively) with FFM and CSS were evaluated using Cox models. The impact of ADT use on accuracy of the CAPRA-based CaPSURE model for CSS was assessed. The discriminatory ability of the CAPRA model and modified models incorporating GP-5 and ADT use were compared using the C-index. RESULTS Increasing CAPRA score correlated with worse FFM and CSS, and was prognostic for FFM and CSS for the overall cohort. CAPRA showed poorer discrimination for FFM and CSS in patients treated with EBRT+LTAD than those who received EBRT alone or EBRT+STAD. The addition of GP-5 and ADT use to CAPRA score increased the predictive accuracy of the CAPRA model for both FFM (C-index 0.809 vs. 0.779, P

Background In prostate cancer, end points that reliably portend prognosis and treatment benefit (surrogate end points) can accelerate therapy development. Although surrogate end point candidates have been evaluated in the context of radiotherapy and short-term androgen deprivation (AD), potential surrogates under long-term (24 month) AD, a proven therapy in high-risk localized disease, have not been investigated. Materials and Methods In the NRG/RTOG 9202 randomized trial (N = 1,520) of short-term AD (4 months) versus long-term AD (LTAD; 28 months), the time interval free of biochemical failure (IBF) was evaluated in relation to clinical end points of prostate cancer–specific survival (PCSS) and overall survival (OS). Survival modeling and landmark analysis methods were applied to evaluate LTAD benefit on IBF and clinical end points, association between IBF and clinical end points, and the mediating effect of IBF on LTAD clinical end point benefits. Results LTAD was superior to short-term AD for both biochemical failure (BF) and the clinical end points. Men remaining free of BF for 3 years had relative risk reductions of 39% for OS and 73% for PCSS. Accounting for 3-year IBF status reduced the LTAD OS benefit from 12% (hazard ratio [HR], 0.88; 95% CI, 0.79 to 0.98) to 6% (HR, 0.94; 95% CI, 0.83 to 1.07). For PCSS, the LTAD benefit was reduced from 30% (HR, 0.70; 95% CI, 0.52 to 0.82) to 6% (HR, 0.94; 95% CI, 0.72 to 1.22). Among men with BF, by 3 years, 50% of subsequent deaths were attributed to prostate cancer, compared with 19% among men free of BF through 3 years. Conclusion The IBF satisfied surrogacy criteria and identified the benefit of LTAD on disease-specific survival and OS. The IBF may serve as a valid end point in clinical trials and may also aid in risk monitoring after initial treatment.

The objective of the study was to investigate prostate-specific antigen (PSA) nadir (nPSA) and time to nPSA (TnPSA) as prognostic variables for outcomes after definitive high-dose (75 Gy) external beam radiation therapy (RT) without androgen deprivation therapy while correcting for immortal-time bias.nPSA and TnPSA were available for 410 patients. nPSA and TnPSA's impact on freedom from biochemical failure, freedom from metastasis, and prostate cancer-specific survival was assessed on univariate and multivariate analysis using Kaplan-Meier and Cox proportional hazards regression. Outcomes were also evaluated relative to the time since achieving nPSA and not relative to the time of RT, given the intrinsic time bias in TnPSA.Median nPSA was 0.7 ng/mL (interquartile range: 0.4 to 1.1), with a median TnPSA of 25.0 months (IQR: 15.0 to 40.0). On univariate analysis both nPSA and TnPSA were predictive of all endpoints: freedom from biochemical failure, freedom from metastasis, and prostate cancer-specific survival, as categorical (all P0.0001) and continuous (all P0.01) variables. However, after adjusting for immortal-time bias the benefit of long TnPSA was mostly lost. On Cox proportional hazards, a TnPSA12 months did have worse prognosis for biochemical failure and distant metastasis as compared with longer TnPSA, but for those who achieved nadir12 months from the time of RT the TnPSA was no longer prognostic.For dose-escalated RT a lower nPSA is prognostic, but the benefit of a long TnPSA is largely an immortal-time bias and that a longer TnPSA is not in and of itself a significant favorable factor except as compared with those with the shortest TnPSA of12 months.

To describe 5- and 10-year rates of metastasis-free survival (MFS) stratified by Gleason score (GS) and prostate-specific antigen doubling time (PSADT) for patients receiving salvage radiation therapy (SRT) after biochemical recurrence (BR) postradical prostatectomy (RP).A total of 236 patients who underwent SRT without receiving concomitant androgen deprivation therapy at a single institution after BR post-RP were retrospectively reviewed. The Kaplan-Meier methods and log-rank analysis were used to determine the MFS rates.Median follow-up post-SRT was 7.1 years. As of last follow-up, 59 men (25%) had developed metastasis. On univariate analysis, both GS and PSADT predicted MFS (P0.001). Five- and 10-year rates of MFS were calculated for patients with GS 2 to 6, 7, and 8 to 10 and for patients with PSADT 3, 3 to 9, 9 to 15, and15 months, who received no additional salvage therapy until the development of metastases. The 5- and 10-year MFS for GS 8 to 10 were 62% and 50%, respectively, compared with 94% at both 5 and 10 years for GS 2 to 6. The 5- and 10-year MFS for PSADT 3 months were 70% and 61%, respectively, compared with 100% and 90% at 5 and 10 years, respectively, for PSADT15 months.After BR post-RP, SRT results in low 5- and 10-year rates of metastasis after initial BR. Importantly, a substantial proportion of patients with high-risk disease (GS 8 to 10 or PSADT 3 mo) are free from metastasis at these same time points. Therefore, SRT should not be withheld from patients based solely on the presence of adverse disease risk factors.

Background: Although prostate cancer (PCa) is hypothesized to differ in nature between younger versus older patients, the underlying molecular distinctions are poorly understood. We hypothesized that high-throughput transcriptomic analysis would elucidate biological differences in PCas arising in younger versus older men, and would nominate potential age-specific biomarkers and therapeutic targets. Methods: The high-density Affymetrix GeneChip platform, encompassing >1 million genomic loci, was utilized to assess gene expression in 1090 radical prostatectomy samples from patients with long-term follow-up. We identified genes associated with metastatic progression by 10 years post-treatment in younger (age

Purpose To report sexual health–related quality of life outcomes and utilization and efficacy of sexual aids in a contemporary cohort of patients treated for localized prostate cancer. Patients and Methods Between 2008 and 2013, 471 consecutive men with localized prostate cancer were treated on 2 institutional protocols (NCT01766492, NCT01618851) or on a prospective institutional registry with patient-reported health-related quality of life. All patients were treated with ultra-hypofractionated radiation therapy. Erectile function (EF) was defined as “firm enough for intercourse” with or without aids per Expanded Prostate Cancer Index Composite-26 (n = 222 at baseline); results apply to this cohort unless specifically noted. Sexual aid utilization and efficacy were patient reported. Multivariable analysis of EF was performed. Results Median follow-up was 60 months, median age was 67 years, and 70% had intermediate- or high-risk disease per National Comprehensive Cancer Network guidelines. At 24 and 60 months, questionnaire response rates were 86% and 67%, and EF was retained in 53% and 41%, respectively. Baseline sexual aid utilization was 37% (n = 82) and was associated with lower 24-month EF preservation on multivariable analysis (adjusted odds ratio 0.49, 95% confidence interval 0.26-0.92). By 60 months, 70% of men had tried aids. Of those who found aids helpful at baseline, 84% to 89% reported continued benefit at 24 to 60 months. Among aid-naive patients, efficacy was 80% with first-time use within 12 months and 70% more than 12 months after radiation therapy (P = .02). Among men who developed erectile dysfunction but found sexual aids helpful, 25% were not current users at 60 months. Conclusions One-third of men used sexual aids at baseline, which doubled by 5 years after radiation therapy. Self-reported efficacy was high and sustained. Despite significant declines in EF, a number of men reported helpfulness of aids but were not active users. Future study is required to understand drivers of aid utilization to optimize posttreatment sexual function.

Purpose The long-term effects of neoadjuvant androgen deprivation therapy (NADT) with radiation therapy on participant-reported health-related quality of life (HRQOL) have not been characterized in prospective multicenter studies. We evaluated HRQOL for 2 years among participants undergoing radiation therapy (RT) with or without NADT for newly diagnosed, early-stage prostate cancer. Methods and Materials We analyzed longitudinal cohort data from the Prostate Cancer Outcomes and Satisfaction with Treatment Quality Assessment Consortium to ascertain the HRQOL trajectory of men receiving NADT with external beam RT (EBRT) or brachytherapy. HRQOL was measured using the expanded prostate cancer index composite 26-item questionnaire at 2, 6, 12, and 24 months after the initiation of NADT. We used the χ 2 or Fisher exact test to compare the shift in percentages between groups that did or did not receive NADT. Analyses were conducted at the 2-sided 5% significance level. Results For subjects receiving EBRT, questions regarding the ability to have an erection, ability to reach an orgasm, quality of erections, frequency of erections, ability to function sexually, and lack of energy were in a significantly worse dichotomized category for the patients receiving NADT. Comparing the baseline versus 24-month outcomes, 24%, 23%, and 30% of participants receiving EBRT plus NADT shifted to the worse dichotomized category for the ability to reach an orgasm, quality of erections, and ability to function sexually compared with 14%, 13%, and 16% in the EBRT group, respectively. Conclusions Compared with baseline, at 2 years, participants receiving NADT plus EBRT compared with EBRT alone had worse HRQOL, as measured by the ability to reach orgasm, quality of erections, and ability to function sexually. However, no difference was found in the ability to have an erection, frequency of erections, overall sexual function, hot flashes, breast tenderness/enlargement, depression, lack of energy, or change in body weight. The improved survival in intermediate- and high-risk patients receiving NADT and EBRT necessitates pretreatment counseling of the HRQOL effect of NADT and EBRT.

BACKGROUND Biochemical failure (BF) after radiation therapy is defined on the basis of a rising prostate-specific antigen (PSA) level (A1 failure) or any event that prompts the initiation of salvage androgen-deprivation therapy without PSA failure (A2). It was hypothesized that A2 failure may have a different prognosis.

39 Background: Hydrogel spacers are a tool to improve dosimetry and overall quality of life with limited follow-up in men receiving radiotherapy for prostate cancer. This present study is a pooled analysis of a prospective cohorts with long-term follow-up quality of life (QOL) data with or without hydrogel spacers to minimize dose adjacent organs at risk. Methods: QOL was examined using the Expanded Prostate Cancer Index Composite (EPIC) to compare mean changes from baseline. A total of 215 patients from a randomized multi-institutional trial of radiation with or without hydrogel spacer with a QOL end-point were pooled with 165 non-randomized patients from a single institution with prospective QOL collection in both patients with or without hydrogel spacer. The proportions of men with minimally important differences (MIDs) relative to pre-treatment baseline in each domain were tested using repeated measures logistic models with pre-specified thresholds for clinically significant decline. Results: A total of 380 men were evaluated (64% with spacer and 36% without) with QOL data being available for 199 men beyond 24 months of follow-up (median: 39.5 months, range: 31-71.4 mo). Treatment with spacer was associated with less decline in average long-term bowel QOL (89.4 for control and 94.7 for experimental) with differences at > 2 years meeting the threshold of MID difference between cohorts (Bowel Score Difference from baseline: control = -5.1 spacer = 0.3 Diff = -5.4 p = 0.0003). When evaluated over time men without spacer were more likely to have 1xMID (5 points) declines in bowel QOL (p = 0.01). At long-term follow-up 1xMID was 36% without spacer vs 14% with spacer (p = 0.0006 OR = 3.5) while 2x MID was seen in 19% vs 6% (p = 0.008 OR = 3.6). The use of spacer was associated with improved bowel frequency (p = 0.002), reduced bleeding (p = 0.005) and less overall bowel problems (p = 0.007). Conclusions: In this pooled analysis of QOL after prostate radiotherapy with up to 5-years of follow-up utilization of a hydrogel spacer was associated with preservation of bowel QOL. This QOL benefit was preserved with long-term follow-up.

Age discrimination is defined as “the denial of privilege or other unfair treatment based on the age of the person who is discriminated against,” and is a topic that has been studied at length in the field of oncology. For instance, despite obtaining similar survival benefit as younger patients, elderly patients are less likely to receive either surgery or radiation therapy (RT) for oropharyngeal squamous cell carcinoma. With rectal cancer, patients older than age 65 are less likely to receive preoperative radiotherapy, which has been demonstrated to reduce local recurrence rates and is widely considered as the standard of care for intermediate and locally advanced disease. Alarmingly, age-based discrimination is especially prevalent in men with high-risk prostate cancer; some have noted that for men older than 75 years of age with high-risk prostate cancer, 67% received primary androgendeprivation therapy (ADT) or no therapy at all, and only 33% received any local therapy. With recent guidelines recommending against prostate-specific antigen screening and increased attention given to the role of active surveillance for low-risk prostate cancer, it is easy to lose sight of the fact that prostate cancer is a leading cause of cancer mortality in men, second only to lung cancer. Ultimately, the majority of men diagnosed with locally advanced or high-risk prostate cancer will succumb to their disease within 15 years with conservative treatment, regardless of their age at diagnosis. Yet numerous studies have demonstrated widespread undertreatment of high-risk prostate cancer in older men, despite the observation that older men are more likely to have high-risk disease and account for approximately half of deaths as a result of prostate cancer. Furthermore, undertreatment of high-risk prostate cancer is a growing problem, with an increasing use of primary ADT monotherapy over time. Given that an average 75-year-old man in the United States has a remaining life expectancy of 11 years, and that the 10-year cause-specific mortality from conservatively treated high-risk prostate cancer is approximately 26%, this represents a serious potential for age-dependent bias against therapy. Therefore, it is important to assess the potential benefits of both ADT and RT in the treatment of high-risk prostate cancer in elderly men. Randomized controlled trials (RCTs) performed by both the EORTC (European Organisation for Research and Treatment of Cancer) and RTOG (Radiation Therapy Oncology Group) in men who were an average of 70 years of age demonstrated that the addition of long-term ADT to RT for locally advanced prostate cancer resulted in up to a 16% absolute improvement in survival at 5 years. Initially it was unclear if the survival benefit was attributable to eradication of micrometastases with systemic therapy or to ablation of local disease that could later serve as a reservoir for metastasis. In findings from two subsequent RCTs (also in men with an average age of 70 years), adding RT to ADT demonstrated that improved local control with externalbeam RT contributed significantly to the observed survival benefits, with an absolute improvement in overall survival (OS) of 8% to 9% at 7 to 10 years. A third RCT with shorter follow-up and a smaller sample size also demonstrated improvements in clinical/biochemical progression–free survival and metastasis-free survival with the addition of RT to ADT. On the basis of these three trials, there is little question that for patients with locally advanced prostate cancer, use of ADT alone provides inadequate treatment with inferior outcomes in comparison to ADT with RT. These findings are now reflected in guidelines from the European Association of Urology, the American Urological Association, and the National Comprehensive Cancer Network, which, in essence, recommend that primary therapy with ADT alone should be considered only for patients who are not candidates for definitive therapy. How these results apply to older men who are not well represented in the prospective clinical trials is an area of critical unmet need that is in part addressed by the population-based observational study performed by Bekelman et al. Using SEER-Medicare data from patients who were treated between 1995 and 2007, the authors first restricted analysis to men similar to those enrolled onto the RCTs, focusing on men younger than 75 years of age with high-volume tumors, and their results demonstrate similar relative and absolute benefits for cause-specific and OS to those observed in the phase III trials with the addition of RT to ADT. This is an intuitive and reassuring finding: that the results observed in selected patients enrolled onto RCTs seem applicable to a similar group of men receiving care in the community. However, more importantly, the authors then extend their analysis to assess the generalizability of these findings to two groups who are not well represented in the RCTs: men with screendetected high-risk prostate cancer and elderly men older than age 75 years. Here, too, they observed substantial improvements with the addition of RT to ADT with a 50% reduction in the risk of dying as a JOURNAL OF CLINICAL ONCOLOGY E D I T O R I A L VOLUME 33 NUMBER 7 MARCH 1 2015

BACKGROUND Data continue to emerge on the relative merits of different treatment modalities for prostate cancer. The objective of this study was to compare patient-reported quality-of-life (QOL) outcomes after proton therapy (PT) and intensity-modulated radiation therapy (IMRT) for prostate cancer. METHODS A comparison was performed of prospectively collected QOL data using the Expanded Prostate Cancer Index Composite (EPIC) questionnaire. QOL data were collected during the first 2 years after treatment for men who received PT and IMRT. PT was delivered to 1243 men at a single center at doses from 76 grays (Gy) to 82 Gy. IMRT was delivered to 204 men who were included in the Prostate Cancer Outcomes and Satisfaction with Treatment Quality Assessment (PROSTQA) study in doses from 75.6 Gy to 79.4 Gy. The Wilcoxon rank-sum test was used to compare EPIC outcomes by modality using baseline-adjusted scores at different time points. Individual questions were assessed by converting to binary outcomes and testing with generalized estimating equations. RESULTS No differences were observed in summary score changes for bowel, urinary incontinence, urinary irritative/obstructive, and sexual domains between the 2 cohorts. However, more men who received IMRT reported moderate/big problems with rectal urgency (P = 0.02) and frequent bowel movements (P = 0.05) than men who received PT. CONCLUSIONS There were no differences in QOL summary scores between the IMRT and PT cohorts during early follow-up (up to 2-years). Response to individual questions suggests possible differences in specific bowel symptoms between the 2 cohorts. These outcomes highlight the need for further comparative studies of PT and IMRT. Cancer 2014;120:1076–1082. © 2013 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

Purpose To investigate the maximum tumor diameter (MTD) of the dominant prostate cancer nodule in the radical prostatectomy specimen as a prognostic factor for outcome in patients treated with salvage external beam radiation therapy (SRT) for a rising prostate-specific antigen (PSA) value after radical prostatectomy. Methods and Materials From an institutional cohort of 575 patients treated with SRT, data on MTD were retrospectively collected. The impact of MTD on biochemical failure (BF), metastasis, and prostate cancer-specific mortality (PCSM) was assessed on univariate and multivariate analysis using Kaplan-Meier and Cox proportional hazards models. Results In the 173 patients with MTD data available, median follow-up was 77 months (interquartile range, 47-104 months) after SRT, and median MTD was 18 mm (interquartile range, 13-22 mm). Increasing MTD correlated with increasing pT stage, Gleason score, presence of seminal vesicle invasion, and lymph node invasion. Receiver operating characteristic curve analysis identified MTD of >14 mm to be the optimal cut-point. On univariate analysis, MTD >14 mm was associated with an increased risk of BF ( P =.02, hazard ratio [HR] 1.8, 95% confidence interval [CI] 1.2-2.8), metastasis ( P =.002, HR 4.0, 95% CI 2.1-7.5), and PCSM ( P =.02, HR 8.0, 95% CI 2.9-21.8). On multivariate analysis MTD >14 mm remained associated with increased BF ( P =.02, HR 1.9, 95% CI 1.1-3.2), metastasis ( P =.02, HR 3.4, 95% CI 1.2-9.2), and PCSM ( P =.05, HR 9.7, 95% CI 1.0-92.4), independent of extracapsular extension, seminal vesicle invasion, positive surgical margins, pre-RT PSA value, Gleason score, and pre-RT PSA doubling time. Conclusions For patients treated with SRT for a rising PSA value after prostatectomy, MTD at time of radical prostatectomy is independently associated with BF, metastasis, and PCSM. Maximum tumor diameter should be incorporated into clinical decision making and future clinical risk assessment tools for those patients receiving SRT.

BACKGROUND The presence of Gleason pattern 5 (GP5) at radical prostatectomy (RP) has been associated with worse clinical outcome; however, this pathologic variable has not been assessed in patients receiving salvage radiation therapy (SRT) after a rising prostate-specific antigen level. METHODS A total of 575 patients who underwent primary RP for localized prostate cancer and subsequently received SRT at a tertiary medical institution were reviewed retrospectively. Primary outcomes of interest were biochemical failure (BF), distant metastasis (DM), and prostate cancer–specific mortality (PCSM), which were assessed via univariate analysis and Fine and Grays competing risks multivariate models. RESULTS On pathologic evaluation, 563 (98%) patients had a documented Gleason score (GS). The median follow-up post-SRT was 56.7 months. A total of 60 (10.7%) patients had primary, secondary, or tertiary GP5. On univariate analysis, the presence of GP5 was prognostic for BF (hazard ratio [HR] 3.3; P

To validate the prognostic value of interval to biochemical failure (IBF) in patients with high-risk prostate cancer (HiRPCa) treated with combined-modality radiation therapy (CMRT) with or without androgen deprivation therapy (ADT).We conducted a retrospective review of HiRPCa (prostate-specific antigen20 ng/mL, Gleason score [GS] 8-10, or clinical T stage T3-T4) treated with either dose-escalated external beam radiation therapy (EBRT) or CMRT. Interval to biochemical failure was classified as ≤18 or18 months from the end of all therapy to the date of biochemical failure (BF). Kaplan-Meier methods and Cox proportional hazards regression were used to evaluate the prognostic value of IBF ≤18 months for distant metastasis (DM) and prostate cancer-specific mortality (PCSM).Of 958 patients with a median follow-up of 63.2 months, 175 patients experienced BF. In those with BF, there were no differences in pretreatment clinical characteristics between the EBRT and CMRT groups, except for a higher proportion of patients with GS 8-10 in the CMRT group (70% vs 52%, P=.02). Median IBF after all therapy was 24.0 months (interquartile range 9.6-46.0) in the EBRT group and 18.9 months (interquartile range 9.2-34.5) in the CMRT group (P=.055). On univariate analysis, IBF ≤18 months was associated with increased risk of DM and PCSM in the entire cohort and the individual EBRT and CMRT groups. On multivariate analysis, only GS 9-10 and IBF ≤18 months, but not the radiation therapy regimen or ADT use, predicted DM (hazard ratio [HR] 3.7, P.01, 95% confidence interval [CI] 1.4-10.3 for GS 9-10; HR 3.9, P.0001, 95% CI 2.4-6.5 for IBF ≤18 months) and PCSM (HR 14.8, P.009, 95% CI 2.0-110 for GS 9-10; HR 4.4, P.0001, 95% CI 2.4-8.1 for IBF ≤18 months).Short IBF was highly prognostic for higher DM and PCSM in patients with HiRPCa. The prognostic value of IBF for DM and PCSM was not affected by the radiation therapy regimen or ADT use.

Purpose To evaluate patients treated with external beam radiation therapy as part of the multicenter Prostate Cancer Outcomes and Satisfaction with Treatment Quality Assessment (PROSTQA), to identify factors associated with posttreatment patient-reported bowel health-related quality of life (HRQOL). Methods and Materials Pretreatment characteristics and treatment details among 292 men were evaluated using a general linear mixed model for their association with measured HRQOL by the Expanded Prostate Cancer Index Composite instrument through 2 years after enrollment. Results Bowel HRQOL had a median score of 100 (interquartile range 91.7-100) pretreatment and 95.8 (interquartile range 83.3-100) at 2 years, representing new moderate/big problems in 11% for urgency, 7% for frequency, 4% for bloody stools, and 8% for an overall bowel problems. Baseline bowel score was the strongest predictor for all 2-year endpoints. In multivariable models, a volume of rectum ≥25% treated to 70 Gy (V70) yielded a clinically significant 9.3-point lower bowel score (95% confidence interval [CI] 16.8-1.7, P =.015) and predicted increased risks for moderate to big fecal incontinence ( P =.0008). No other radiation therapy treatment-related variables influenced moderate to big changes in rectal HRQOL. However, on multivariate analyses V70 ≥25% was associated with increases in small, moderate, or big problems with the following: incontinence (3.9-fold; 95% CI 1.1-13.4, P =.03), rectal bleeding (3.6-fold; 95% CI 1.3-10.2, P =.018), and bowel urgency (2.9-fold; 95% CI 1.1-7.6, P =.026). Aspirin use correlated with a clinically significant 4.7-point lower bowel summary score (95% CI 9.0-0.4, P =.03) and an increase in small, moderate, or big problems with bloody stools (2.8-fold; 95% CI 1.2-6.4, P =.018). Intensity modulated radiation therapy was associated with higher radiation therapy doses to the prostate and lower doses to the rectum but did not independently correlate with bowel HRQOL. Conclusion After contemporary dose-escalated external beam radiation therapy up to 11% of patients have newly identified moderate/big problems with bowel HRQOL 2 years after treatment. Bowel HRQOL is related to baseline function, rectal V70, and aspirin use. Finally, our findings validate the commonly utilized cut-point of rectal V70 ≥25% as having significant impact on patient-reported outcomes.

BACKGROUND: Recent studies have suggested differing toxicity patterns for patients with prostate cancer who receive treatment with 3-dimensional conformal radiotherapy (3DCRT), intensity-modulated radiotherapy (IMRT), or proton beam therapy (PBT). METHODS: The authors reviewed patient-reported outcomes data collected prospectively using validated instruments that assessed bowel and urinary quality of life (QOL) for patients with localized prostate cancer who received 3DCRT (n = 123), IMRT (n = 153) or PBT (n = 95). Clinically meaningful differences in mean QOL scores were defined as those exceeding half the standard deviation of the baseline mean value. Changes from baseline were compared within groups at the first post-treatment follow-up (2-3 months from the start of treatment) and at 12 months and 24 months. RESULTS: At the first post-treatment follow-up, patients who received 3DCRT and IMRT, but not those who received PBT, reported a clinically meaningful decrement in bowel QOL. At 12 months and 24 months, all 3 cohorts reported clinically meaningful decrements in bowel QOL. Patients who received IMRT reported clinically meaningful decrements in the domains of urinary irritation/obstruction and incontinence at the first post-treatment follow-up. At 12 months, patients who received PBT, but not those who received IMRT or 3DCRT, reported a clinically meaningful decrement in the urinary irritation/obstruction domain. At 24 months, none of the 3 cohorts reported clinically meaningful changes in urinary QOL. CONCLUSIONS: Patients who received 3DCRT, IMRT, or PBT reported distinct patterns of treatment-related QOL. Although the timing of toxicity varied between the cohorts, patients reported similar modest QOL decrements in the bowel domain and minimal QOL decrements in the urinary domains at 24 months. Prospective randomized trials are needed to further examine these differences. Cancer 2013. © 2013 American Cancer Society.

Purpose To study the impact of daily rotations and translations of the prostate on dosimetric coverage during radiation therapy (RT). Methods and Materials Real-time tracking data for 26 patients were obtained during RT. Intensity modulated radiation therapy plans meeting RTOG 0126 dosimetric criteria were created with 0-, 2-, 3-, and 5-mm planning target volume (PTV) margins. Daily translations and rotations were used to reconstruct prostate delivered dose from the planned dose. D95 and V79 were computed from the delivered dose to evaluate target coverage and the adequacy of PTV margins. Prostate equivalent rotation is a new metric introduced in this study to quantify prostate rotations by accounting for prostate shape and length of rotational lever arm. Results Large variations in prostate delivered dose were seen among patients. Adequate target coverage was met in 39%, 65%, and 84% of the patients for plans with 2-, 3-, and 5-mm PTV margins, respectively. Although no correlations between prostate delivered dose and daily rotations were seen, the data showed a clear correlation with prostate equivalent rotation. Conclusions Prostate rotations during RT could cause significant underdosing even if daily translations were managed. These rotations should be managed with rotational tolerances based on prostate equivalent rotations.

BACKGROUND: The objective of this study was to determine whether the addition of low-dose-rate brachytherapy or androgen-deprivation therapy (ADT) improves clinical outcome in patients with high-risk prostate cancer (HiRPCa) who received dose-escalated radiotherapy (RT). METHODS: Between 1995 and 2010, 958 patients with HiRPCa were treated at Schiffler Cancer Center (n = 484) or at the University of Michigan (n = 474) by receiving either dose-escalated external-beam RT (EBRT) (n = 510; minimum prescription dose, 75 grays [Gy]; median dose, 78 Gy) or combined-modality RT (CMRT) consisting of 103Pd implants (n = 369) or 125I implants (n = 79) both with pelvic irradiation (median prescription dose, 45 Gy). The cumulative incidences of biochemical failure (BF) and prostate cancer-specific mortality (PCSM) were estimated by using the Kaplan-Meier method and Fine and Gray regression analysis. RESULTS: The median follow-up was 63.2 months (interquartile range, 35.4-99.0 months), and 250 patients were followed for >8 years. Compared with CMRT, patients who received EBRT had higher prostate-specific antigen levels, higher tumor classification, lower Gleason sum, and more frequent receipt of ADT for a longer duration. The 8-year incidence BF and PCSM among patients who received EBRT was 40% (standard error, 38%-44%) and 13% (standard error, 11%-15%) compared with 14% (standard error, 12%-16%; P < .0001) and 7% (standard error 6%-9%; P = .003) among patients who received CMRT. On multivariate analysis, the hazard ratios (HRs) for BF and PCSM were 0.35 (95% confidence interval [CI], 0.23-0.52; P < .0001) and 0.41 (95% CI, 0.23-0.75; P < .003), favoring CMRT. Increasing duration of ADT predicted decreased BF (P = .04) and PCSM (P = .001), which was greatest with long-term ADT (BF: HR, 0.33; P < .0001; 95% CI, 0.21-0.52; PCSM: HR, 0.30; P = .001; 95% CI, 0.15-0.6) even in the subgroup that received CMRT. CONCLUSIONS: In this retrospective comparison, both low-dose-rate brachytherapy boost and ADT were associated with decreased risks of BF and PCSM compared with EBRT. Cancer 2013. © 2012 American Cancer Society.

Purpose To investigate the prognostic utility of the percentage of cancer volume (PCV) in needle biopsy specimens for prostate cancer patients treated with dose-escalated external beam radiotherapy. Methods and Materials The outcomes were analyzed for 599 men treated for localized prostate cancer with external beam radiotherapy to a minimal planning target volume dose of 75 Gy (range, 75–79.2). We assessed the effect of PCV and the pretreatment and treatment-related factors on the freedom from biochemical failure, freedom from metastasis, cause-specific survival, and overall survival. Results The median number of biopsy cores was 7 (interquartile range, 6–12), median PCV was 10% (interquartile range, 2.5–25%), and median follow-up was 62 months. The PCV correlated with the National Comprehensive Cancer Network risk group and individual risk features, including T stage, prostate-specific antigen level, Gleason score, and percentage of positive biopsy cores. On log–rank analysis, the PCV stratified by quartile was prognostic for all endpoints, including overall survival. In addition, the PCV was a stronger prognostic factor than the percentage of positive biopsy cores when the two metrics were analyzed together. On multivariate analysis, the PCV predicted a worse outcome for all endpoints, including freedom from biochemical failure, (hazard ratio, 1.9; p = .0035), freedom from metastasis (hazard ratio, 1.7, p = .09), cause-specific survival (hazard ratio, 3.9, p = .014), and overall survival (hazard ratio, 1.8, p = .02). Conclusions For patients treated with dose-escalated external beam radiotherapy, the volume of cancer in the biopsy specimen adds prognostic value for clinically relevant endpoints, particularly in intermediate- and high-risk patients. Although the PCV determination is more arduous than the percentage of positive biopsy cores, it provides superior risk stratification.

To analyze prognostic factors in patients with high-risk prostate cancer treated with dose-escalated external-beam radiation therapy (EBRT) and androgen deprivation (ADT).Between 1998 and 2008 at the University of Michigan Medical Center, 718 men were consecutively treated with EBRT to at least 75 Gy. Seven definitions of high-risk prostate cancer, applying to 11-33% of patients, were evaluated. Biochemical failure (BF), salvage ADT use, metastatic progression, and prostate cancer-specific mortality (PCSM) were estimated by the Kaplan-Meier method and Cox proportional hazards regression.Each high-risk definition was associated with increased BF (hazard ratio [HR] 2.8-3.9, p0.0001), salvage ADT use (HR 3.9-6.3, p0.0001), metastasis (HR 3.7-6.6, p0.0001), and PCSM (HR 3.7-16.2, p0.0001). Furthermore, an increasing number of high-risk features predicted worse outcome. Adjuvant ADT yielded significant reductions in both metastases (HR 0.19-0.38, p0.001) and PCSM (HR 0.38-0.50, p0.05) for all high-risk definitions (with the exception of clinical Stage T3-4 disease) but improved BF only for those with elevated Gleason scores (p0.03, HR 0.25-0.48). When treated with ADT and dose-escalated EBRT, patients with Gleason scores 8 to 10, without other high-risk features, had 8-year freedom from BF of 74%, freedom from distant metastases of 93%, and cause-specific survival of 92%, with salvage ADT used in 16% of patients.Adjuvant ADT results in a significant improvement in clinical progression and PCSM across multiple definitions of high-risk disease even with dose-escalated EBRT. There is a subset of patients, characterized by multiple high-risk features or the presence of Gleason Pattern 5, who remain at significant risk for metastasis and PCSM despite current treatment.

Purpose To examine the prognostic utility of the percentage of positive cores (PPC) at the time of prostate biopsy for patients treated with dose-escalated external beam radiation therapy. Methods and materials We performed a retrospective analysis of patients treated at the University of Michigan Medical Center to at least 75 Gy. Patients were stratified according to PPC by quartile, and freedom from biochemical failure (nadir + 2 ng/mL), freedom from metastasis (FFM), cause-specific survival (CSS), and overall survival (OS) were assessed by log-rank test. Receiver operator characteristic (ROC) curve analysis was used to determine the optimal cut point for PPC stratification. Finally, Cox proportional hazards multivariate regression was used to assess the impact of PPC on clinical outcome when adjusting for National Comprehensive Cancer Network (NCCN) risk group and androgen deprivation therapy. Results PPC information was available for 651 patients. Increasing-risk features including T stage, prostate-specific antigen, Gleason score, and NCCN risk group were all directly correlated with increasing PPC. On log-rank evaluation, all clinical endpoints, except for OS, were associated with PPC by quartile, with worse clinical outcomes as PPC increased, with the greatest impact seen in the highest quartile (>66.7% of cores positive). ROC curve analysis confirmed that a cut point using two-thirds positive cores was most closely associated with CSS (p = 0.002; area under ROC curve, 0.71). On univariate analysis, stratifying patients according to PPC less than or equal to 66.7% vs. PPC greater than 66.7% was prognostic for freedom from biochemical failure (p = 0.0001), FFM (p = 0.0002), and CSS (p = 0.0003) and marginally prognostic for OS (p = 0.055). On multivariate analysis, after adjustment for NCCN risk group and androgen deprivation therapy use, PPC greater than 66.7% increased the risk for biochemical failure (p = 0.0001; hazard ratio [HR], 2.1 [95% confidence interval (CI), 1.4-3.0]) and FFM (p = 0.05; HR, 1.7 [95% CI, 1.1-2.9]) and marginally increased the risk for CSS (p = 0.057; HR, 2.1 [95% CI, 1.0-4.6]). Conclusion PPC at the time of biopsy adds prognostic value for clinically meaningful endpoints for patients treated with dose-escalated radiation therapy. This was particularly true for NCCN-defined intermediate- and high-risk patients.

BACKGROUND: After external beam radiation therapy (EBRT) for prostate cancer, a short interval to biochemical failure of

Purpose: Currently, radiologic response of brain tumors is assessed according to the Macdonald criteria 10 weeks from the start of therapy. There exists a critical need to identify nonresponding patients early in the course of their therapy for consideration of alternative treatment strategies. Our study assessed the effectiveness of the parametric response map (PRM) imaging biomarker to provide for an earlier measure of patient survival prediction. Experimental Design: Forty-five high-grade glioma patients received concurrent chemoradiation. Quantitative MRI including apparent diffusion coefficient (ADC) and relative cerebral blood volume (rCBV) maps were acquired pretreatment and 3 weeks midtreatment on a prospective institutional-approved study. PRM, a voxel-by-voxel image analysis method, was evaluated as an early prognostic biomarker of overall survival. Clinical and conventional MR parameters were also evaluated. Results: Multivariate analysis showed that PRMADC+ in combination with PRMrCBV− obtained at week 3 had a stronger correlation to 1-year and overall survival rates than any baseline clinical or treatment response imaging metric. The composite biomarker identified three distinct patient groups, nonresponders [median survival (MS) of 5.5 months, 95% CI: 4.4–6.6 months], partial responders (MS of 16 months, 95% CI: 8.6–23.4 months), and responders (MS has not yet been reached). Conclusions: Inclusion of PRMADC+ and PRMrCBV− into a single imaging biomarker metric provided early identification of patients resistant to standard chemoradiation. In comparison to the current standard of assessment of response at 10 weeks (Macdonald criteria), the composite PRM biomarker potentially provides a useful opportunity for clinicians to identify patients who may benefit from alternative treatment strategies. Clin Cancer Res; 17(14); 4751–60. ©2011 AACR.

Importance Optimizing radiation therapy techniques for localized prostate cancer can affect patient outcomes. Dose escalation improves biochemical control, but no prior trials were powered to detect overall survival (OS) differences. Objective To determine whether radiation dose escalation to 79.2 Gy compared with 70.2 Gy would improve OS and other outcomes in prostate cancer. Design, Setting, and Participants The NRG Oncology/RTOG 0126 randomized clinical trial randomized 1532 patients from 104 North American Radiation Therapy Oncology Group institutions March 2002 through August 2008. Men with stage cT1b to T2b, Gleason score 2 to 6, and prostate-specific antigen (PSA) level of 10 or greater and less than 20 or Gleason score of 7 and PSA less than 15 received 3-dimensional conformal radiation therapy or intensity-modulated radiation therapy to 79.2 Gy in 44 fractions or 70.2 Gy in 39 fractions. Main Outcomes and Measures Time to OS measured from randomization to death due to any cause. American Society for Therapeutic Radiology and Oncology (ASTRO)/Phoenix definitions were used for biochemical failure. Acute (≤90 days of treatment start) and late radiation therapy toxic effects (>90 days) were graded using the National Cancer Institute Common Toxicity Criteria, version 2.0, and the RTOG/European Organisation for the Research and Treatment of Cancer Late Radiation Morbidity Scoring Scheme, respectively. Results With a median follow-up of 8.4 (range, 0.02-13.0) years in 1499 patients (median [range] age, 71 [33-87] years; 70% had PSA P = .98). The 8-year cumulative rates of distant metastases were 4% for the 79.2-Gy arm and 6% for the 70.2-Gy arm (HR, 0.65; 95% CI, 0.42-1.01; P = .05). The ASTRO and Phoenix biochemical failure rates at 5 and 8 years were 31% and 20% with 79.2 Gy and 47% and 35% with 70.2 Gy, respectively (both P P = .006 [HR, 1.39; 95% CI, 1.10-1.77] and P = .003 [HR, 1.59; 95% CI, 1.17-2.16], respectively). Conclusions and Relevance Despite improvements in biochemical failure and distant metastases, dose escalation did not improve OS. High doses caused more late toxic effects but lower rates of salvage therapy. Trial Registration clinicaltrials.gov Identifier:NCT00033631

Purpose To assess whether a new method of quantifying therapy-associated hemodynamic alterations may help to distinguish pseudoprogression from true progression in patients with high-grade glioma. Patients and Methods Patients with high-grade glioma received concurrent chemoradiotherapy. Relative cerebral blood volume (rCBV) and blood flow (rCBF) maps were acquired before chemoradiotherapy and at week 3 during treatment on a prospective institutional review board–approved study. Pseudoprogression was defined as imaging changes 1 to 3 months after chemoradiotherapy that mimic tumor progression but stabilized or improved without change in treatment or for which resection revealed radiation effects only. Clinical and conventional magnetic resonance (MR) parameters, including average percent change of rCBV and CBF, were evaluated as potential predictors of pseudoprogression. Parametric response map (PRM), an innovative, voxel-by-voxel method of image analysis, was also performed. Results Median radiation dose was 72 Gy (range, 60 to 78 Gy). Of 27 patients, stable disease/partial response was noted in 13 patients and apparent progression was noted in 14 patients. Adjuvant temozolomide was continued in all patients. Pseudoprogression occurred in six patients. Based on PRM analysis, a significantly reduced blood volume (PRMrCBV) at week 3 was noted in patients with progressive disease as compared with those with pseudoprogression (P < .01). In contrast, change in average percent rCBV or rCBF, MR tumor volume changes, age, extent of resection, and Radiation Therapy Oncology Group recursive partitioning analysis classification did not distinguish progression from pseudoprogression. Conclusion PRMrCBV at week 3 during chemoradiotherapy is a potential early imaging biomarker of response that may be helpful in distinguishing pseudoprogression from true progression in patients with high-grade glioma.

Purpose: The PI3K/Akt/mTOR prosurvival pathway is frequently up-regulated in soft tissue sarcoma. Mammalian target of rapamycin (mTOR) inhibitors, such as rapamycin, have recently shown clinical benefit in soft tissue sarcoma, and mTOR inhibition has also been associated with radiosensitization of carcinoma and endothelial cells. This study tested the hypothesis that rapamycin radiosensitizes soft tissue sarcoma and endothelial cells in vitro and in vivo through the inhibition of mTOR. Experimental Design: Colony formation assays were done to determine the radiosensitizing properties of rapamycin on three human soft tissue sarcoma cell lines (SK-LMS-1, SW-872, and HT-1080) and human dermal microvascular endothelial cells (HDMEC). The functional effects of rapamycin and radiation on the endothelial compartment were evaluated with microvascular sprouting assays. The in vivo radiosensitizing activity of rapamycin was assessed with s.c. SK-LMS-1 nude mice xenografts treated with concurrent daily rapamycin, radiation, or both for three weeks. Results: In vitro radiosensitization was shown in all three soft tissue sarcoma cell lines with minimally cytotoxic doses of rapamycin. SK-LMS-1 xenografts displayed significant tumor growth delay with rapamycin and radiation compared with either treatment alone. Radiation resulted in transient increased mTOR function, whereas rapamycin abolished this signaling in irradiated and unirradiated samples. In HDMEC, rapamycin and radiation reduced microvessel sprouting, but did not alter colony formation. Conclusions: Minimally cytotoxic concentrations of rapamycin inhibited the mTOR cascade in culture and in vivo while radiosensitizing soft tissue sarcoma, and produced synergistic effects with radiation on HDMEC microvessel formation. By targeting both tumor and endothelial compartments, rapamycin produced potent radiosensitization of soft tissue sarcoma xenografts. Clinical trials combining rapamycin and radiotherapy in soft tissue sarcoma are warranted.

For the treatment of squamous cell cancer of the head and neck (SCCHN), the assessment of treatment response is traditionally accomplished by volumetric measurements and has been suggested to be prognostic for an eventual response to treatment. An early evaluation response during the course of radiation therapy could provide an opportunity to tailor treatment to individual patients. Diffusion magnetic resonance imaging (MRI) allows for the quantification of tissue water diffusion values, thus treatment-induced loss of tumor cells will result in the increase in water mobility at the microscopic level, which can be detected as an increase in tumor diffusion values before any volumetric changes occur. We evaluated the use of diffusion MRI as an imaging biomarker of treatment response in an orthotopic mouse model of SCCHN. Mice with murine squamous cells expressing the yeast transgene cytosine deaminase were treated with 5-fluorocytosine (5FC), ionizing radiation, and combined therapy and were compared with control animals both during and after treatment for changes in tumor volumes, diffusion values, and survival. Radiation therapy had minimal effect on volumetric growth rate, diffusion, or survival. Although 5FC and combination treatment resulted in similar reductions in tumor volumes, the combination treatment elicited a much greater increase in tumor diffusion values, which correlated with improved survival. Thus, diffusion MRI as an imaging biomarker has a potential for early evaluation of the response to chemoradiation treatment in SCCHN.

Purpose: In a previous report, a recombinant luciferase reporter, activated during apoptosis via caspase-3 cleavage, was developed for imaging of apoptosis using bioluminescence. The ability to noninvasively image apoptosis in vivo could dramatically benefit the preclinical development of therapeutics targeting the apoptotic pathway. In this study, we examined the use of 5-fluorouracil (5-FU) for sensitizing D54 tumors to tumor necrosis factor α–related apoptosis–inducing ligand (TRAIL) therapy by monitoring apoptotic activity in vivo using bioluminescence imaging. Experimental Design: Using our apoptosis imaging platform and diffusion magnetic resonance imaging (MRI), we monitored the antitumor effects of 5-FU, TRAIL, and 5-FU + TRAIL using D54 xenografts. Additionally, volumetric and histologic analyses were done for correlation with findings from bioluminescence imaging and diffusion MRI. Results: Bioluminescence imaging showed that therapy with TRAIL alone produced an initial 400% increase in apoptotic activity that rapidly diminished during the 10-day treatment period despite continued therapy. In contrast, concomitant 5-FU and TRAIL therapy elicited an apoptotic response that was sustained throughout the entire therapeutic course. Using diffusion MRI, an enhanced tumor response was detected when concomitant therapy was given versus TRAIL-alone therapy. Last, concomitant therapy resulted in a prolonged growth delay (∼9 days) compared with TRAIL alone (∼4 days). Conclusion: We showed that concomitant 5-FU and TRAIL therapy indeed enhanced apoptotic activity in vivo, which translated into greater tumor control. Moreover, this technique sheds light on the synergy of 5-FU and TRAIL as evidenced by differences in the temporal activation of caspase-3 resulting from the different therapeutic regimens.

Purpose Long-term (LT) androgen suppression (AS) with radiation therapy (RT) is a standard treatment of high-risk, localized prostate cancer (PCa). Radiation Therapy Oncology Group 9902 was a randomized trial testing the hypothesis that adjuvant combination chemotherapy (CT) with paclitaxel, estramustine, and oral etoposide plus LT AS plus RT would improve overall survival (OS). Methods and Materials Patients with high-risk PCa (prostate-specific antigen 20-100 ng/mL and Gleason score [GS] ≥7 or clinical stage ≥T2 and GS ≥8) were randomized to RT and AS (AS + RT) alone or with adjuvant CT (AS + RT + CT). CT was given as four 21-day cycles, delivered beginning 28 days after 70.2 Gy of RT. AS was given as luteinizing hormone-releasing hormone for 24 months, beginning 2 months before RT plus an oral antiandrogen for 4 months before and during RT. The study was designed based on a 6% improvement in OS from 79% to 85% at 5 years, with 90% power and a 2-sided alpha of 0.05. Results A total of 397 patients (380 eligible) were randomized. The patients had high-risk PCa, 68% with GS 8 to 10 and 34% T3 to T4 tumors, and median prostate-specific antigen of 22.6 ng/mL. The median follow-up period was 9.2 years. The trial closed early because of excess thromboembolic toxicity in the CT arm. The 10-year results for all randomized patients revealed no significant difference between the AS + RT and AS + RT + CT arms in OS (65% vs 63%; P =.81), biochemical failure (58% vs 54%; P =.82), local progression (11% vs 7%; P =.09), distant metastases (16% vs 14%; P =.42), or disease-free survival (22% vs 26%; P =.61). Conclusions NRG Oncology RTOG 9902 showed no significant differences in OS, biochemical failure, local progression, distant metastases, or disease-free survival with the addition of adjuvant CT to LT AS + RT. The trial results provide valuable data regarding the natural history of high-risk PCa treated with LT AS + RT and have implications for the feasibility of clinical trial accrual and tolerability using CT for PCa.

Anterior-predominant prostate cancer (APC) is an incompletely understood entity which can be difficult to sample via transrectal biopsy. Seemingly favorable biopsy results may belie the potential aggressiveness of these tumors. Here, we attempt to characterize APC by retrospectively examining the clinicopathologic features of APC at radical prostatectomy and comparing our findings with prior biopsy information. We found that 17.4 % of patients in our study had APC. APC demonstrated a significantly lower (P value < 0.05) Gleason score (GS) and pathologic stage than non-APC tumors, including the absence of seminal vesicle invasion by APC. A subset (5.6 %) of APC consisted of high-grade tumors (GS ≥ 8), and these tumors were more often detected on transperineal saturation biopsy than non-transperineal saturation (i.e., transrectal ultrasound guided) biopsy strategies. Four patients (7 %) without transperineal saturation biopsy exhibited a significantly worse GS at RP than biopsy, compared to five patients (36 %) with transperineal saturation biopsy. Our findings corroborate the difficulty in detecting APC and suggest that APC is not a uniform disease with a wholly indolent phenotype. Dedicated long-term outcome data are needed in these patients. Additionally, alternative pathologic staging parameters may be necessary.

PurposePerirectal spacing, whereby biomaterials are placed between the prostate and rectum, shows promise in reducing rectal dose during prostate cancer radiation therapy. A prospective multicenter randomized controlled pivotal trial was performed to assess outcomes following absorbable spacer (SpaceOAR system) implantation.Methods and MaterialsOverall, 222 patients with clinical stage T1 or T2 prostate cancer underwent computed tomography (CT) and magnetic resonance imaging (MRI) scans for treatment planning, followed with fiducial marker placement, and were randomized to receive spacer injection or no injection (control). Patients received postprocedure CT and MRI planning scans and underwent image guided intensity modulated radiation therapy (79.2 Gy in 1.8-Gy fractions). Spacer safety and impact on rectal irradiation, toxicity, and quality of life were assessed throughout 15 months.ResultsSpacer application was rated as “easy” or “very easy” 98.7% of the time, with a 99% hydrogel placement success rate. Perirectal spaces were 12.6 ± 3.9 mm and 1.6 ± 2.0 mm in the spacer and control groups, respectively. There were no device-related adverse events, rectal perforations, serious bleeding, or infections within either group. Pre-to postspacer plans had a significant reduction in mean rectal V70 (12.4% to 3.3%, P