Mortality reduction and cumulative excess incidence (CEI) in the prostate-specific antigen (PSA) screening era.

The extent to which PSA screening is related to prostate cancer mortality reduction in the United States (US) is controversial. US Surveillance, Epidemiology, and End Results Program (SEER) data from 1980 to 2016 were examined to assess the relationship between prostate cancer mortality and cumulative excess incidence (CEI) in the PSA screening era and to clarify the impact of race on this relationship. CEI was considered as a surrogate for the intensity of prostate cancer screening with PSA testing and subsequent biopsy as appropriate. Data from 163,982,733 person-years diagnosed with 544,058 prostate cancers (9 registries, 9% of US population) were examined. Strong inverse linear relationships were noted between CEI and prostate cancer mortality, and 317,356 prostate cancer deaths were avoided. Eight regions of the US demonstrated prostate cancer mortality reduction of 46.0-63.7%. On a per population basis, the lives of more black men than white men were saved in three of four registries with sufficient black populations for comparison. Factor(s) independent of CEI (potential effects of treatment advances) explained 14.6% of the mortality benefit (p-value = 0.3357) while there was a significant main effect of CEI (effect = -0.0064; CI: [-0.0088, -0.0040]; p-value < 0.0001). Therefore, there is a strong relationship between CEI and prostate cancer mortality reduction that was not related to factors independent of screening utilization. Minority populations have experienced large mortality reductions in the context of PSA mass utilization.

Outcomes following radical prostatectomy or external beam radiation for veterans with Gleason 9 and 10 prostate cancer.

BACKGROUND: The optimal upfront treatment modality for patients with nonmetastatic Gleason Score 9 and 10 prostate cancer (GS 9-10 PCa) is unknown. METHODS: We conducted a retrospective cohort study of patients in the Veterans Health Administration (VHA) with GS 9-10 PCa treated with radical prostatectomy (RP) or external beam radiation therapy with androgen deprivation therapy (EBRT+ADT) from 1/2000 to 12/2010. Outcomes included overall survival (OS), distant metastasis-free survival (DMFS), and salvage/adjuvant therapy-free survival (SAFS), as assessed by Kaplan-Meier analysis. RESULTS: We identified 1220 veterans with GS 9-10 PCa; 335 were treated with RP, and 885 were treated with EBRT+ADT. With a median follow-up of 9.9 years, propensity score-matched analyses demonstrated that RP had superior 10-year OS (70.8% [RP] vs. 61.2% [EBRT+ADT], p < 0.001), 10-year DMFS rates were similar between RP (76.7%) and EBRT+ADT (81.0%), and 10-year SAFS rates were lower for RP vs EBRT + ADT (35.2% [RP] vs. 75.2% [EBRT+ADT], p < 0.001). The receipt of salvage ADT was higher with upfront RP (51.9% vs. 26.1%, p < 0.001), despite receipt of adjuvant/salvage EBRT in 41.8% of RP patients. Among patients treated with RP, there were no differences in outcomes by race. However, higher survival rates were noted among Black patients treated with EBRT+ADT compared with White patients. CONCLUSIONS: This analysis demonstrated higher 10-year OS rates among men treated with upfront RP versus EBRT+ADT, though missing confounders and similar DMFS rates suggest the long-term cause-specific OS rates may be similar. We also highlight real-world outcomes of a diverse patient population in the VHA and improved outcomes for Black patients receiving EBRT+ADT.

Addition of Androgen-Deprivation Therapy or Brachytherapy Boost to External Beam Radiotherapy for Localized Prostate Cancer: A Network Meta-Analysis of Randomized Trials.

PURPOSE: In men with localized prostate cancer, the addition of androgen-deprivation therapy (ADT) or a brachytherapy boost (BT) to external beam radiotherapy (EBRT) have been shown to improve various oncologic end points. Practice patterns indicate that those who receive BT are significantly less likely to receive ADT, and thus we sought to perform a network meta-analysis to compare the predicted outcomes of a randomized trial of EBRT plus ADT versus EBRT plus BT. MATERIALS AND METHODS: A systematic review identified published randomized trials comparing EBRT with or without ADT, or EBRT (with or without ADT) with or without BT, that reported on overall survival (OS). Standard fixed-effects meta-analyses were performed for each comparison, and a meta-regression was conducted to adjust for use and duration of ADT. Network meta-analyses were performed to compare EBRT plus ADT versus EBRT plus BT. Bayesian analyses were also performed, and a rank was assigned to each treatment after Markov Chain Monte Carlo analyses to create a surface under the cumulative ranking curve. RESULTS: Six trials compared EBRT with or without ADT (n = 4,663), and 3 compared EBRT with or without BT (n = 718). The addition of ADT to EBRT improved OS (hazard ratio [HR], 0.71 [95% CI, 0.62 to 0.81]), whereas the addition of BT did not significantly improve OS (HR, 1.03 [95% CI, 0.78 to 1.36]). In a network meta-analysis, EBRT plus ADT had improved OS compared with EBRT plus BT (HR, 0.68 [95% CI, 0.52 to 0.89]). Bayesian modeling demonstrated an 88% probability that EBRT plus ADT resulted in superior OS compared with EBRT plus BT. CONCLUSION: Our findings suggest that current practice patterns of omitting ADT with EBRT plus BT may result in inferior OS compared with EBRT plus ADT in men with intermediate- and high-risk prostate cancer. ADT for these men should remain a critical component of treatment regardless of radiotherapy delivery method until randomized evidence demonstrates otherwise.

Population-Based Observational Studies in Oncology: Proceed With Caution.

A principle goal of research in Oncology is to determine the optimal treatment for our patients. This often takes the form of comparing 2 existing therapies to one another to determine which is superior, or to introduce a new therapy and determine if it is superior or noninferior to the existing standard of care. This type of research is termed comparative effectiveness research (CER), and the gold-standard is through the conduct of randomized trials. This is the preferred approach, and the only true methodologic approach that can assign a cause-and-effect relationship between a treatment effect and the observed outcome. An alternative approach that is gaining popularity is the use of population-based registry analysis given that it is quicker, cheaper, and easier to perform. However, there are unavoidable forms of bias and confounding that exist when using observational research to perform CER, and recent evidence suggests that population-based CER often results in erroneous results, and that statistical methods to minimize bias are ineffective to overcome the numerous limitations of these databases. In this article, the strengths and weaknesses of both randomized and observational research will be discussed.

The current state of randomized clinical trial evidence for prostate brachytherapy.

Interstitial brachytherapy is one of several curative therapeutic options for the treatment of localized prostate cancer. In this review, we summarize all available randomized data to support the optimal use of prostate brachytherapy. Evidence from completed randomized controlled trials is the focus of this review with a presentation also of important ongoing trials. Gaps in knowledge are identified where future investigation may be fruitful with intent to inspire well-designed prospective studies with standardized treatment that focuses on improving oncological outcomes, reducing morbidity, or maintaining quality of life.

Association of Black Race With Prostate Cancer-Specific and Other-Cause Mortality.

Importance: Black men are more likely to die of prostate cancer than white men. In men with similar stages of disease, the contribution of biological vs nonbiological differences to this observed disparity is unclear. Objective: To quantify the association of black race with long-term survival outcomes after controlling for known prognostic variables and access to care among men with prostate cancer. Design, Setting, and Participants: This multiple-cohort study included updated individual patient-level data of men with clinical T1-4N0-1M0 prostate cancer from the following 3 cohorts: Surveillance, Epidemiology, and End Results (SEER [n = 296 273]); 5 equal-access regional medical centers within the Veterans Affairs health system (VA [n = 3972]); and 4 pooled National Cancer Institute-sponsored Radiation Therapy Oncology Group phase 3 randomized clinical trials (RCTs [n = 5854]). Data were collected in the 3 cohorts from January 1, 1992, through December 31, 2013, and analyzed from April 27, 2017, through April 13, 2019. Exposures: In the VA and RCT cohorts, all patients received surgery and radiotherapy, respectively, with curative intent. In SEER, radical treatment, hormone therapy, or conservative management were received. Main Outcomes and Measures: Prostate cancer-specific mortality (PCSM). Secondary measures included other-cause mortality (OCM). To adjust for demographic-, cancer-, and treatment-related baseline differences, inverse probability weighting (IPW) was performed. Results: Among the 306 100 participants included in the analysis (mean [SD] age, 64.9 [8.9] years), black men constituted 52 840 patients (17.8%) in the SEER cohort, 1513 (38.1%) in the VA cohort, and 1129 (19.3%) in the RCT cohort. Black race was associated with an increased age-adjusted PCSM hazard (subdistribution hazard ratio [sHR], 1.30; 95% CI, 1.23-1.37; P < .001) within the SEER cohort. After IPW adjustment, black race was associated with a 0.5% (95% CI, 0.2%-0.9%) increase in PCSM at 10 years after diagnosis (sHR, 1.09; 95% CI, 1.04-1.15; P < .001), with no significant difference for high-risk men (sHR, 1.04; 95% CI, 0.97-1.12; P = .29). No significant differences in PCSM were found in the VA IPW cohort (sHR, 0.85; 95% CI, 0.56-1.30; P = .46), and black men had a significantly lower hazard in the RCT IPW cohort (sHR, 0.81; 95% CI, 0.66-0.99; P = .04). Black men had a significantly increased hazard of OCM in the SEER (sHR, 1.30; 95% CI, 1.27-1.34; P < .001) and RCT (sHR, 1.17; 95% CI, 1.06-1.29; P = .002) IPW cohorts. Conclusions and Relevance: In this study, after adjustment for nonbiological differences, notably access to care and standardized treatment, black race did not appear to be associated with inferior stage-for-stage PCSM. A large disparity remained in OCM for black men with nonmetastatic prostate cancer.

Stereotactic Body Radiation Therapy for Localized Prostate Cancer: A Systematic Review and Meta-Analysis of Over 6,000 Patients Treated On Prospective Studies.

PURPOSE: Utilization of stereotactic body radiation therapy (SBRT) for treatment of localized prostate cancer is increasing. Guidelines and payers variably support the use of prostate SBRT. We therefore sought to systematically analyze biochemical recurrence-free survival (bRFS), physician-reported toxicity, and patient-reported outcomes after prostate SBRT. METHODS AND MATERIALS: A systematic search leveraging Medline via PubMed and EMBASE for original articles published between January 1990 and January 2018 was performed. This was supplemented by abstracts with sufficient extractable data from January 2013 to March 2018. All prospective series assessing curative-intent prostate SBRT for localized prostate cancer reporting bRFS, physician-reported toxicity, and patient-reported quality of life with a minimum of 1-year follow-up were included. The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Meta-analyses were performed with random-effect modeling. Extent of heterogeneity between studies was determined by the I2 and Cochran's Q tests. Meta-regression was performed using Hartung-Knapp methods. RESULTS: Thirty-eight unique prospective series were identified comprising 6116 patients. Median follow-up was 39 months across all patients (range, 12-115 months). Ninety-two percent, 78%, and 38% of studies included low, intermediate, and high-risk patients. Overall, 5- and 7-year bRFS rates were 95.3% (95% confidence interval [CI], 91.3%-97.5%) and 93.7% (95% CI, 91.4%-95.5%), respectively. Estimated late grade ≥3 genitourinary and gastrointestinal toxicity rates were 2.0% (95% CI, 1.4%-2.8%) and 1.1% (95% CI, 0.6%-2.0%), respectively. By 2 years post-SBRT, Expanded Prostate Cancer Index Composite urinary and bowel domain scores returned to baseline. Increasing dose of SBRT was associated with improved biochemical control (P = .018) but worse late grade ≥3 GU toxicity (P = .014). CONCLUSIONS: Prostate SBRT has substantial prospective evidence supporting its use, with favorable tumor control, patient-reported quality of life, and levels of toxicity demonstrated. SBRT has sufficient evidence to be supported as a standard treatment option for localized prostate cancer while ongoing trials assess its potential superiority.

Stereotactic Body Radiation Therapy for Hepatocellular Carcinoma: Current State and Future Opportunities.

Hepatocellular carcinoma is a rising cause of morbidity and mortality in the USA and around the world. Surgical resection and liver transplantation are the preferred management strategies; however, less than 30% of patients are eligible for surgery. Stereotactic body radiation therapy is a promising local treatment option for non-surgical candidates. Local control rates between 95 and 100% have been reported at 1-2 years post-treatment, and classical radiation-induced liver disease described with conventional radiation is an unlikely complication from stereotactic radiotherapy. Enrollment in randomized trials will be essential in establishing the role of stereotactic radiation in treatment paradigms for hepatocellular carcinoma.

Comparison of Population-Based Observational Studies With Randomized Trials in Oncology.

PURPOSE: Comparative efficacy research performed using population registries can be subject to significant bias. There is an absence of objective data demonstrating factors that can sufficiently reduce bias and provide accurate results. METHODS: MEDLINE was searched from January 2000 to October 2016 for observational studies comparing two treatment regimens for any diagnosis of cancer, using SEER, SEER-Medicare, or the National Cancer Database. Reporting quality and statistical methods were assessed using components of the STROBE criteria. Randomized trials comparing the same treatment regimens were identified. Primary outcome was correlation between survival hazard ratio (HR) estimates provided by the observational studies and randomized trials. Secondary outcomes included agreement between matched pairs and predictors of agreement. RESULTS: Of 3,657 studies reviewed, 350 treatment comparisons met eligibility criteria and were matched to 121 randomized trials. There was no significant correlation between the HR estimates reported by observational studies and randomized trials (concordance correlation coefficient, 0.083; 95% CI, -0.068 to 0.230). Forty percent of matched studies were in agreement regarding treatment effects (κ, 0.037; 95% CI, -0.027 to 0.1), and 62% of the observational study HRs fell within the 95% CIs of the randomized trials. Cancer type, data source, reporting quality, adjustment for age, stage, or comorbidities, use of propensity weighting, instrumental variable or sensitivity analysis, and well-matched study population did not predict agreement. CONCLUSION: We were unable to identify any modifiable factor present in population-based observational studies that improved agreement with randomized trials. There was no agreement beyond what is expected by chance, regardless of reporting quality or statistical rigor of the observational study. Future work is needed to identify reliable methods for conducting population-based comparative efficacy research.

Patient-Reported Sexual Aid Utilization and Efficacy After Radiation Therapy for Localized Prostate Cancer.

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-naïve 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.

Erectile function after stereotactic body radiotherapy for localized prostate cancer.

OBJECTIVE: To elucidate the functional erection rate after prostate stereotactic body radiotherapy (SBRT) and to develop a comprehensive prognostic model of outcomes after treatment. PATIENTS AND METHODS: Between 2008 and 2013, 373 consecutive men with localized prostate cancer were treated with SBRT at a single academic institution as part of a prospective clinical trial or prospective registry. Prospective longitudinal patient-reported health-related quality of life (HRQoL) data was collected using the Expanded Prostate Cancer Index Composite (EPIC)-26 instrument. Functional erections were strictly defined as 'firm enough for intercourse' according to EPIC-26. Detailed comorbidity data were also collected. Logistic regression models were used to predict 24- and 60-month functional erection rates. Observed erection rates after SBRT were compared with those after other radiation therapies (external beam radiation therapy [EBRT] and brachytherapy) using prospectively validated models. RESULTS: The median (interquartile range) follow-up was 56 (37-73) months and the response rate at 2 years was 84%. For those with functional erections at baseline, 57% and 45% retained function at 24 and 60 months, respectively. On multivariable analysis for 24-month erectile function, significant variables included higher baseline sexual HRQoL (adjusted odds ratio [aOR] 1.55 per 10 points, 95% confidence interval [CI] 1.37-1.74; P < 0.001) and older age (aOR 0.66 per 10 years, 95% CI 0.43-1.00; P = 0.05). At 60 months, baseline HRQoL and age remained associated with erectile function, along with body mass index (aOR 0.45, 95% CI 0.26-0.78; P < 0.001). The 24- and 60-month models had excellent discrimination (c-index 0.81 and 0.84, respectively). Erection rates after SBRT were not statistically different from model-predicted rates after EBRT or brachytherapy for the whole cohort and the cohort with baseline erectile function. CONCLUSIONS: Intermediate- to long-term post-SBRT erectile function results are promising and not significantly different from other radiotherapy techniques. Clinicians can use our prognostic model to counsel patients regarding expected erectile function after SBRT.

Impact of Biochemical Failure After Salvage Radiation Therapy on Prostate Cancer-specific Mortality: Competition Between Age and Time to Biochemical Failure.

BACKGROUND: Disease progression following salvage radiotherapy (SRT) for prostate cancer (PC) is common, and the time to biochemical recurrence (BCR) is heterogeneous. OBJECTIVE: To describe the temporal distribution and clinical impact of BCR following SRT and model outcomes using patient age and time to BCR from SRT. DESIGN, SETTING, AND PARTICIPANTS: A retrospective multi-institutional study included 547 consecutive men with lymph node-negative PC receiving SRT from 1985 to 2013. The median follow-up after SRT was 8.4 yr. Intervention All men received SRT with three-dimensional or intensity-modulated RT. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: BCR was defined as a rise in prostate-specific antigen (PSA) ≥0.2ng/ml above the PSA nadir followed by a sequentially equal or higher value. Additional outcomes included distant metastasis (DM), PC-specific mortality (PCSM), and overall mortality (OM). Cox proportional hazards models, a landmark analysis, and comparison of c-indices were used. Cumulative incidence curves were estimated from a Fine and Gray regression model. RESULTS AND LIMITATIONS: The estimated 10-yr cumulative incidence of BCR was 60%. Of the 274 men experiencing BCR, 149 (54%) had BCR within 18 mo of SRT. BCR ≤18 mo after SRT was associated with a higher risk of DM (hazard ratio [HR] 7.44, 95% confidence interval [CI] 4.91-11.3; p<0.001), PCSM (HR 12.3, 95% CI 5.95-25.2; p<0.001), and OM (HR 2.85, 95% CI 1.94-4.17; p<0.001). We provide a model to estimate the cumulative incidence of DM and PCSM using age and time to BCR. The retrospective nature of our analysis limits our findings. CONCLUSIONS: A strikingly large proportion of men experience early BCR following SRT and are at higher risk of DM and PCSM. Novel predictive biomarkers are needed to identify men harboring micrometastatic disease to avoid potentially futile local therapies or allow for intensification of systemic therapies. PATIENT SUMMARY: Many men will develop biochemical recurrence of prostate cancer after salvage radiotherapy. Men with biochemical recurrence within 18 mo of salvage radiotherapy constitute a cohort at higher risk of distant metastasis and prostate cancer-specific mortality.

External beam radiation therapy with or without low-dose-rate brachytherapy: Analysis of favorable and unfavorable intermediate-risk prostate cancer patients.

PURPOSE: To compare the tumor control and toxicity in men with intermediate-risk prostate cancer treated with either external beam radiation therapy (EBRT) or EBRT plus low-dose-rate brachytherapy (combo-RT). METHODS AND MATERIALS: Between 1995 and 2012, 579 men with intermediate-risk prostate cancer were treated with either EBRT (n = 388) or combo-RT (n = 191). Outcomes assessed included biochemical recurrence-free survival (bRFS), distant metastasis-free survival (DMFS), and cumulative incidence of genitourinary (GU) and gastrointestinal toxicity. Favorable and unfavorable intermediate-risk subgroups were analyzed. RESULTS: Median followup was 7.5 years. Combo-RT group had improved 10-year bRFS compared with EBRT (91.7% vs. 75.4%, p = 0.014). On multivariable analysis, combo-RT (hazard ratio, 0.48; 95% confidence interval: 0.25, 0.92; p = 0.03) was associated with improved bRFS. Combo-RT had significantly improved bRFS compared with EBRT in the unfavorable subgroup (p = 0.02) but not in the favorable subgroup (p = 0.37). DMFS was similar within the entire cohort and by risk group. Combo-RT was associated with an increased rate in the 6-year cumulative incidence of Grade 3 GU toxicity (hazard ratio, 3.48; 95% confidence interval: 1.1, 11.1; p = 0.026); however, 57% of Grade 3 GU toxicity was resolved, 29% had partial improvement, and only 1 patient had persistent Grade 3 GU toxicity. CONCLUSIONS: In intermediate-risk prostate cancer, combo-RT improved bRFS but not DMFS and increased Grade 3 GU toxicity. The bRFS benefit was limited to unfavorable intermediate-risk patients.

Cardiac Events After Radiation Therapy: Combined Analysis of Prospective Multicenter Trials for Locally Advanced Non-Small-Cell Lung Cancer.

Purpose Radiation therapy is a critical component in the care of patients with non-small-cell lung cancer (NSCLC), yet cardiac injury after treatment is a significant concern. Therefore, we wished to elucidate the incidence of cardiac events and their relationship to radiation dose to the heart. Patients and Materials Study eligibility criteria included patients with stage II to III NSCLC treated on one of four prospective radiation therapy trials at two centers from 2004 to 2013. All cardiac events were reviewed and graded per Common Terminology Criteria for Adverse Events (v4.03). The primary end point was the development of a grade ≥ 3 cardiac event. Results In all, 125 patients met eligibility criteria; median follow-up was 51 months for surviving patients. Median prescription dose was 70 Gy, 84% received concurrent chemotherapy, and 27% had pre-existing cardiac disease. Nineteen patients had a grade ≥ 3 cardiac event at a median of 11 months (interquartile range, 6 to 24 months), and 24-month cumulative incidence was 11% (95% CI, 5% to 16%). On multivariable analysis (MVA), pre-existing cardiac disease (hazard ratio [HR], 2.96; 95% CI, 1.07 to 8.21; P = .04) and mean heart dose (HR, 1.07/Gy; 95% CI, 1.02 to 1.13/Gy; P = .01) were significantly associated with grade ≥ 3 cardiac events. Analyzed as time-dependent variables on MVA analysis, both disease progression (HR, 2.15; 95% CI, 1.54 to 3.00) and grade ≥ 3 cardiac events (HR, 1.76; 95% CI, 1.04 to 2.99) were associated with decreased overall survival. However, disease progression (n = 71) was more common than grade ≥ 3 cardiac events (n = 19). Conclusion The 24-month cumulative incidence of grade ≥ 3 cardiac events exceeded 10% among patients with locally advanced NSCLC treated with definitive radiation. Pre-existing cardiac disease and higher mean heart dose were significantly associated with higher cardiac event rates. Caution should be used with cardiac dose to minimize risk of radiation-associated injury. However, cardiac risks should be balanced against tumor control, given the unfavorable prognosis associated with disease progression.

Lower Incidence of Esophagitis in the Elderly Undergoing Definitive Radiation Therapy for Lung Cancer.

INTRODUCTION: Most patients with lung cancer are elderly and poorly represented in randomized clinical trials. They are often undertreated because of concerns about their ability to tolerate aggressive treatment. We tested the hypothesis that elderly patients undergoing definitive lung radiation might tolerate treatment differently than younger patients. METHODS: A total of 125 patients who underwent definitive lung radiotherapy were identified from a prospective institutional database (University of Michigan cohort). Logistic regression modeling was performed to assess the impact of age on esophagitis grade 2 or higher or grade 2 or higher and pneumonitis grade 3 or higher or grade 2 or higher, with adjustment for esophageal and lung dose, respectively, as well as for chemotherapy utilization, smoking status, and performance status. The analysis was validated in a large cohort of 691 patients from the Michigan Radiation Oncology Quality Consortium registry, an independent statewide prospective database. RESULTS: In the University of Michigan cohort, multivariable regression models revealed a significant inverse correlation between age and rate of esophagitis for both toxicity levels, (adjusted OR = 0.93 for both models and 95% confidence intervals of 0.88-0.98 and 0.87-0.99), with areas under the curve of 0.747 and 0.721, respectively, demonstrating good fit. This same association was noted in the Michigan Radiation Oncology Quality Consortium cohort. There was no significant association between age and pneumonitis. CONCLUSIONS: There is a lower incidence of esophagitis with increasing age even after adjustment for use of chemotherapy. This is a novel finding in thoracic oncology. No age dependence was noted for pulmonary toxicity. The elderly are able to tolerate definitive thoracic radiation well and should be offered this option when clinically warranted.

Magnetic resonance imaging-guided functional anatomy approach to prostate brachytherapy.

PURPOSE: To provide an MRI based functional anatomy guide to prostate brachytherapy. METHODS AND MATERIALS: We performed a narrative review of periprostatic functional anatomy and the significance of this anatomy in prostate brachytherapy treatment planning. RESULTS: MRI has improved delineation of gross tumor and critical periprostatic structures that have been implicated in toxicity. Furthermore, MRI has revealed the significant anatomic variants and the dynamic nature of these structures that can have significant implications for treatment planning and dosimetry. CONCLUSIONS: The MRI-based functional anatomy approach to prostate brachytherapy takes into account extent of disease, its relation to the patient's individual anatomy, and functional baseline to optimize the therapeutic ratio of prostate cancer treatment.

Predictors of multidomain decline in health-related quality of life after stereotactic body radiation therapy (SBRT) for prostate cancer.

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.

American Brachytherapy Society Task Group Report: Combination of brachytherapy and external beam radiation for high-risk prostate cancer.

PURPOSE: To review outcomes for high-risk prostate cancer treated with combined modality radiation therapy (CMRT) utilizing external beam radiation therapy (EBRT) with a brachytherapy boost. METHODS AND MATERIALS: The available literature for high-risk prostate cancer treated with combined modality radiation therapy was reviewed and summarized. RESULTS: At this time, the literature suggests that the majority of high-risk cancers are curable with multimodal treatment. Several large retrospective studies and three prospective randomized trials comparing CMRT to dose-escalated EBRT have demonstrated superior biochemical control with CMRT. Longer followup of the randomized trials will be required to determine if this will translate to a benefit in metastasis-free survival, disease-specific survival, and overall survival. Although greater toxicity has been associated with CMRT compared to EBRT, recent studies suggest that technological advances that allow better definition and sparing of critical adjacent structures as well as increasing experience with brachytherapy have improved implant quality and the toxicity profile of brachytherapy. The role of androgen deprivation therapy is well established in the external beam literature for high-risk disease, but there is controversy regarding the applicability of these data in the setting of dose escalation. At this time, there is not sufficient evidence for the omission of androgen deprivation therapy with dose escalation in this population. Comparisons with surgery remain limited by differences in patient selection, but the evidence would suggest better disease control with CMRT compared to surgery alone. CONCLUSIONS: Due to a series of technological advances, modern combination series have demonstrated unparalleled rates of disease control in the high-risk population. Given the evidence from recent randomized trials, combination therapy may become the standard of care for high-risk cancers.