Quality of Life in Patients With Low-Risk Prostate Cancer Treated With Hypofractionated vs Conventional Radiotherapy: A Phase 3 Randomized Clinical Trial

Long-Term Analysis of NRG Oncology RTOG 0415: A Randomized Phase III Noninferiority Study Comparing Two Fractionation Schedules in Patients With Low-Risk Prostate Cancer

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.NRG Oncology RTOG 0415 is a randomized phase III noninferiority (NI) clinical trial comparing conventional fractionation (73.8 Gy in 41 fractions) radiotherapy (C-RT) with hypofractionation (H-RT; 70 Gy in 28) in patients with low-risk prostate cancer. The study included 1,092 protocol-eligible patients initially reported in 2016 with a median follow-up of 5.8 years. Updated results with median follow-up of 12.8 years are now presented. The estimated 12-year disease-free survival (DFS) is 56.1% (95% CI, 51.5 to 60.5) for C-RT and 61.8% (95% CI, 57.2 to 66.0) for H-RT. The DFS hazard ratio (H-RT/C-RT) is 0.85 (95% CI, 0.71 to 1.03), confirming NI (P < .001). Twelve-year cumulative incidence of biochemical failure (BF) was 17.0% (95% CI, 13.8 to 20.5) for C-RT and 9.9% (95% CI, 7.5 to 12.6) for H-RT. The HR (H-RT/C-RT) comparing biochemical recurrence between the two arms was 0.55 (95% CI, 0.39 to 0.78). Late grade ≥3 GI adverse event (AE) incidence is 3.2% (C-RT) versus 4.4% (H-RT), with relative risk (RR) for H-RT versus C-RT 1.39 (95% CI, 0.75 to 2.55). Late grade ≥3 genitourinary (GU) AE incidence is 3.4% (C-RT) versus 4.2% (H-RT), RR 1.26 (95% CI, 0.69 to 2.30). Long-term DFS is noninferior with H-RT compared with C-RT. BF is less with H-RT. No significant differences in late grade ≥3 GI/GU AEs were observed between assignments (ClinicalTrials.gov identifier: NCT00331773).

Radiation technique and outcomes following moderately hypofractionated treatment of low risk prostate cancer: a secondary analysis of RTOG 0415

BACKGROUND

While moderately hypofractionated radiotherapy (MHRT) for prostate cancer (PC) is commonly delivered by intensity modulated radiation therapy, IMRT has not been prospectively compared to three-dimensional conformal radiotherapy (3D-CRT) in this context. We conducted a secondary analysis of the phase III RTOG 0415 trial comparing survival and toxicity outcomes for low-risk PC following MHRT with IMRT versus 3D-CRT.

METHODS

RTOG 0415 was a phase III, non-inferiority trial randomizing low-risk PC patients to either MHRT or conventionally fractionated radiation with stratification by RT technique. A secondary analysis for differences in overall survival (OS), biochemical recurrence free survival (BRFS), or toxicity by EPIC scores and Common Terminology Criteria for Adverse Events (CTCAE) was performed.

RESULTS

1079 patients received the allocated intervention with a median follow up of 5.8 years. 79.1% of patients were treated with IMRT and radiation technique was balanced between arms. Across all patients, RT technique was not associated with significant differences in BRFS, OS, or rates of acute and late toxicities. For patients completing MHRT, there was a difference in the late GU toxicity distribution between 3D-CRT and IMRT but no difference in late grade 2 or greater GU or GI toxicity. Stratifying patients by RT technique and fractionation, no significant differences were observed in the minimal clinically important difference (MCID) in EPIC urinary and bowel scores following RT.

CONCLUSIONS

RT technique did not impact clinical outcomes following MHRT for low-risk PC. Despite different late GU toxicity distributions in patients treated with MHRT by IMRT or 3D-CRT, there was no difference in late Grade 2 or greater GU or GI toxicity or patient reported toxicity. Increases in late GU and GI toxicity following MHRT compared to CFRT, as demonstrated in the initial publication of RTOG 0415, do not appear related to a 3D-CRT treatment technique.

Optimizing Clinical Implementation of Hypofractionation: Comprehensive Evidence Synthesis and Practical Guidelines for Low- and Middle-Income Settings

The global cancer burden, especially in low- and middle-income countries (LMICs), worsens existing disparities, amplified by the rising costs of advanced treatments. The shortage of radiation therapy (RT) services is a significant issue in LMICs. Extended conventional treatment regimens pose significant challenges, especially in resource-limited settings. Hypofractionated radiotherapy (HRT) and ultra-hypofractionated/stereotactic body radiation therapy (SBRT) offer promising alternatives by shortening treatment durations. This approach optimizes the utilization of radiotherapy machines, making them more effective in meeting the growing demand for cancer care. Adopting HRT/SBRT holds significant potential, especially in LMICs. This review provides the latest clinical evidence and guideline recommendations for the application of HRT/SBRT in the treatment of breast, prostate, and lung cancers. It emphasizes the critical importance of rigorous training, technology, stringent quality assurance, and safety protocols to ensure precise and secure treatments. Additionally, it addresses practical considerations for implementing these treatments in LMICs, highlighting the need for comprehensive support and collaboration to enhance patient access to advanced cancer care.

Health-related quality of life analyses in nonfunctioning pituitary macroadenoma patients identifies at-risk populations

PURPOSE

The quality of life (QoL) impact of multidisciplinary treatment for patients with nonfunctioning pituitary macroadenomas (NFPMA) is unclear. We sought to investigate associations between patient factors, clinical data, and patient-reported QoL in patients with NFPMA.

METHODS

Patients with treated NFPMA and > 1 year of follow up after transsphenoidal surgery (TSS) and with no evidence of progressive disease were evaluated utilizing the following patient-reported outcome measures: RAND-36-Item Health Survey, Multidimensional Fatigue Inventory, Cognitive Failures Questionnaire.

RESULTS

229 eligible patients completed QoL questionnaires a median of 7.7 years after initial transsphenoidal surgery (TSS). 25% of participants received radiation therapy (RT) a median of 2.0 years (0.1-22.5) after initial TSS. Patients who received RT were younger (median age 46 v 58, p < 0.0001), had larger tumors (28 mm v 22 mm, p < 0.0001), were more likely to have visual symptoms (65% v 34%, p = 0.0002), and were more likely to have hypopituitarism (93% v 62%, p < 0.0001). Patients with hypopituitarism reported worse energy and fatigue and cognitive function (p < 0.03). Patients who received RT reported significantly worse general health, physical health, physical fatigue and cognitive functioning (p < 0.05). The largest QoL differences were in patients who experienced a financial stressor, independent of treatment type.

CONCLUSION

Hypopituitarism, radiation therapy after TSS, and financial stressors are associated with more impaired QoL in patients with NFPMA. Awareness of these factors can better guide use and timing of radiation therapy in addition to identifying patients who can benefit from multidisciplinary surveillance.

Late, persistent, substantial treatment-related symptoms (LAPERS) following low-dose-rate brachytherapy for prostate cancer

PURPOSE

We aim to report 1) prevalence, 2) incidence, and 3) late, persistent, substantial treatment-related symptoms (LAPERS) after low-dose-rate brachytherapy (LDRBT) for prostate cancer.

METHODS AND MATERIALS

The study comprised men treated with LDRBT in a single Australian institution between 2014 and 2019. All men completed the Expanded Prostate Cancer Index Composite 26 (EPIC-26) questionnaire pretreatment, and at regular intervals posttreatment. 'Substantial' symptoms were defined as 'moderate' or 'big' problems in EPIC-26 which assesses the degree of symptom bother for each functional domain. 'Persistent' symptoms were defined as 'substantial' symptoms that present in at least half of the 'late' followup assessments. This provided a binary LAPERS outcome (yes/no). Prevalence (at each time point) and cumulative incidence of substantial symptoms were also reported.

RESULTS

A total of 172 men with 'baseline' and at least three 'late' followup EPIC-26 were included in the study. The median followup was 60 months (IQR: 36-74 months). For overall urinary function, prevalence of substantial symptoms was highest at 10% 6-month posttreatment, with 5-year cumulative incidence of 18%, but only 2% had LAPERS. For overall bowel function, prevalence of substantial symptoms was highest at 7% 12-months posttreatment, with 5-year cumulative incidence of 15%, and only 2% had LAPERS. For sexual function, prevalence of substantial symptoms was highest at 28% 6-months posttreatment, with 5-year cumulative incidence of 49%, and 22% had LAPERS (baseline-adjusted LAPERS 17%).

CONCLUSIONS

There were considerable differences in late toxicities using different toxicity-reporting approaches. LAPERS approach is more reflective of 'true' late toxicities considering duration and persistence of symptoms.

Neighborhood Deprivation and Rurality Associated With Patient-Reported Outcomes and Survival in Men With Prostate Cancer in NRG Oncology RTOG 0415

PURPOSE

Rurality and neighborhood deprivation can contribute to poor patient-reported outcomes, which have not been systematically evaluated in patients with specific cancers in national trials. Our objective was to examine the effect of rurality and neighborhood socioeconomic and environmental deprivation on patient-reported outcomes and survival in men with prostate cancer in NRG Oncology RTOG 0415.

METHODS AND MATERIALS

Data from men with prostate cancer in trial NRG Oncology RTOG 0415 were analyzed; 1,092 men were randomized to receive conventional radiation therapy or hypofractionated radiation therapy. Rurality was categorized as urban or rural. Neighborhood deprivation was assessed using the area deprivation index and air pollution indicators (nitrogen dioxide and particulate matter with a diameter less than 2.5 micrometers) via patient ZIP codes. Expanded Prostate Cancer Index Composite measured cancer-specific quality of life. The Hopkins symptom checklist measured anxiety and depression. EuroQoL-5 Dimension assessed general health.

RESULTS

We analyzed 751 patients in trial NRG Oncology RTOG 0415. At baseline, patients from the most deprived neighborhoods had worse bowel (P = .011), worse sexual (P = .042), and worse hormonal (P = .015) scores; patients from the most deprived areas had worse self-care (P = .04) and more pain (P = .047); and patients from rural areas had worse urinary (P = .03) and sexual (P = .003) scores versus patients from urban areas. Longitudinal analyses showed that the 25% most deprived areas (P = .004) and rural areas (P = .002) were associated with worse EuroQoL-5 Dimension visual analog scale score. Patients from urban areas (hazard ratio, 1.81; P = .033) and the 75% less-deprived neighborhoods (hazard ratio, 0.68; P = .053) showed relative decrease in risk of recurrence or death (disease-free survival).

CONCLUSIONS

Patients with prostate cancer from the most deprived neighborhoods and rural areas had low quality of life at baseline, poor general health longitudinally, and worse disease-free survival. Interventions should screen populations from deprived neighborhoods and rural areas to improve patient access to supportive care services.

Prognostic Values of Gene Copy Number Alterations in Prostate Cancer

Whilst risk prediction for individual prostate cancer (PCa) cases is of a high priority, the current risk stratification indices for PCa management have severe limitations. This study aimed to identify gene copy number alterations (CNAs) with prognostic values and to determine if any combination of gene CNAs could have risk stratification potentials. Clinical and genomic data of 500 PCa cases from the Cancer Genome Atlas stable were retrieved from the Genomic Data Commons and cBioPortal databases. The CNA statuses of a total of 52 genetic markers, including 21 novel markers and 31 previously identified potential prognostic markers, were tested for prognostic significance. The CNA statuses of a total of 51/52 genetic markers were significantly associated with advanced disease at an odds ratio threshold of ≥1.5 or ≤0.667. Moreover, a Kaplan-Meier test identified 27/52 marker CNAs which correlated with disease progression. A Cox Regression analysis showed that the amplification of MIR602 and deletions of MIR602, ZNF267, MROH1, PARP8, and HCN1 correlated with a progression-free survival independent of the disease stage and Gleason prognostic group grade. Furthermore, a binary logistic regression analysis identified twenty-two panels of markers with risk stratification potentials. The best model of 7/52 genetic CNAs, which included the SPOP alteration, SPP1 alteration, CCND1 amplification, PTEN deletion, CDKN1B deletion, PARP8 deletion, and NKX3.1 deletion, stratified the PCa cases into a localised and advanced disease with an accuracy of 70.0%, sensitivity of 85.4%, specificity of 44.9%, positive predictive value of 71.67%, and negative predictive value of 65.35%. This study validated prognostic gene level CNAs identified in previous studies, as well as identified new genetic markers with CNAs that could potentially impact risk stratification in PCa.

Health-related Quality of Life of Patients Treated With Different Fractionation Schedules for Early Prostate Cancer Compared to the Age-standardized General Male Population

BACKGROUND

The effects of radiotherapy (RT) patients' health-related quality of life (HRQoL) are usually compared to those of other treatment modalities instead of HRQoL of the general population in oncological studies. We examined HRQoL of patients with an early prostate cancer (PC) not receiving hormonal treatment up to 3 years after RT using the 15D instrument and the FACT-P questionnaire.

METHODS

The 15D results were compared to those in the age-standardized general male population (N = 952) using an independent-sample t test. The study population (N = 73) received RT either with 78/2 Gy, 60/3 Gy or 36.25/7.25 Gy fractionation.

RESULTS

No significant differences in the mean total HRQoL scores were found between the RT groups and the general male population at any time point. Patients with PC had more depression (P = .015) and distress (P = .029) than the general male population before the treatment and depression up to 3 months after treatment (P = .019), which did not persist at 3 years. The sexual activity dimension had declined by the end of treatment, and this decline persisted 3 years later (P = .033). Excretion functions were worse compared to those in peers at the end of treatment (P < .001) but no longer at 3 months and later after RT. Regarding the FACT-P, HRQoL remained good at 3 years after RT in all the treatment groups and there were no significant differences between the different RT groups at this time point.

CONCLUSION

This study demonstrated that patients treated with RT for early PC had similar HRQoL compared to the age-standardized general male population at 3 years after treatment.

Reporting of tobacco use and tobacco-related analyses in cancer cooperative group clinical trials: a systematic scoping review

BACKGROUND

Continued smoking after a diagnosis of cancer negatively impacts cancer outcomes, but the impact of tobacco on newer treatments options is not well established. Collecting and evaluating tobacco use in clinical trials may advance understanding of the consequences of tobacco use on treatment modalities, but little is known about the frequency of reporting and analysis of tobacco use in cancer cooperative clinical trial groups.

PATIENTS AND METHODS

A comprehensive literature search was conducted to identify cancer cooperative group clinical trials published from January 2017-October 2019. Eligible studies evaluated either systemic and/or radiation therapies, included ≥100 adult patients, and reported on at least one of: overall survival, disease/progression-free survival, response rates, toxicities/adverse events, or quality-of-life.

RESULTS

A total of 91 studies representing 90 trials met inclusion criteria with trial start dates ranging from 1995 to 2015 with 14% involving lung and 5% head and neck cancer patients. A total of 19 studies reported baseline tobacco use; 2 reported collecting follow-up tobacco use. Seven studies reported analysis of the impact of baseline tobacco use on clinical outcomes. There was significant heterogeneity in the reporting of baseline tobacco use: 7 reported never/ever status, 10 reported never/ex-smoker/current smoker status, and 4 reported measuring smoking intensity. None reported verifying smoking status or second-hand smoke exposure. Trials of lung and head and neck cancers were more likely to report baseline tobacco use than other disease sites (83% versus 6%, P < 0.001).

CONCLUSIONS

Few cancer cooperative group clinical trials report and analyze trial participants' tobacco use. Significant heterogeneity exists in reporting tobacco use. Routine standardized collection and reporting of tobacco use at baseline and follow-up in clinical trials should be implemented to enable investigators to evaluate the impact of tobacco use on new cancer therapies.

Volumetric modulated arc therapy (VMAT): a review of clinical outcomes—what is the clinical evidence for the most effective implementation?

Modern conformal radiation therapy using techniques such as modulation, image guidance and motion management have changed the face of radiotherapy today offering superior conformity, efficiency, and reproducibility to clinics worldwide. This review assesses the impact of these advanced radiotherapy techniques on patient toxicity and survival rates reported from January 2017 to September 2020. The main aims are to establish if dosimetric and efficiency gains correlate with improved survival and reduced toxicities and to answer the question ‘What is the clinical evidence for the most effective implementation of VMAT?’. Compared with 3DCRT, improvements have been reported with VMAT in prostate, locally advanced cervical carcinoma and various head and neck applications, leading to the shift in technology to VMAT. Other sites such as thoracic neoplasms and nasopharyngeal carcinomas have observed some improvement with VMAT although not in line with improved dosimetric measures, and the burden of toxicity and the incidence of cancer related deaths remain high, signaling the need to further mitigate toxicity and increase survival. As technological advancement continues, large randomised long-term clinical trials are required to determine the way-forward and offer site-specific recommendations. These studies are usually expensive and time consuming, therefore utilising pooled real-world data in a prospective nature can be an alternative solution to comprehensively assess the efficacy of modern radiotherapy techniques.

Methodological Comparison of Mapping the Expanded Prostate Cancer Index Composite to EuroQoL-5D-3L Using Cross-Sectional and Longitudinal Data: Secondary Analysis of NRG/RTOG 0415

PURPOSE

To compare the predictive ability of mapping algorithms derived using cross-sectional and longitudinal data.

METHODS

This methodological assessment used data from a randomized controlled noninferiority trial of patients with low-risk prostate cancer, conducted by NRG Oncology (ClinicalTrials.gov identifier: NCT00331773), which examined the efficacy of conventional schedule versus hypofractionated radiation therapy (three-dimensional conformal external beam radiation therapy/IMRT). Health-related quality-of-life data were collected using the Expanded Prostate Cancer Index Composite (EPIC), and health utilities were obtained using EuroQOL-5D-3L (EQ-5D) at baseline and 6, 12, 24, and 60 months postintervention. Mapping algorithms were estimated using ordinary least squares regression models through five-fold cross-validation in baseline cross-sectional data and combined longitudinal data from all assessment periods; random effects specifications were also estimated in longitudinal data. Predictive performance was compared using root mean square error. Longitudinal predictive ability of models obtained using baseline data was examined using mean absolute differences in the reported and predicted utilities.

RESULTS

A total of 267 (and 199) patients in the estimation sample had complete EQ-5D and EPIC domain (and subdomain) data at baseline and at all subsequent assessments. Ordinary least squares models using combined data showed better predictive ability (lowest root mean square error) in the validation phase for algorithms with EPIC domain/subdomain data alone, whereas models using baseline data outperformed other specifications in the validation phase when patient covariates were also modeled. The mean absolute differences were lower for models using EPIC subdomain data compared with EPIC domain data and generally decreased as the time of assessment increased.

CONCLUSION

Overall, mapping algorithms obtained using baseline cross-sectional data showed the best predictive performance. Furthermore, these models demonstrated satisfactory longitudinal predictive ability.

Feasibility, pitfalls and results of a structured concept-development phase for a randomized controlled phase III trial on radiotherapy in primary prostate cancer patients

Objective

Failure rate in randomized controlled trials (RCTs) is > 50%, includes safety-problems, underpowered statistics, lack of efficacy, lack of funding or insufficient patient recruitment and is even more pronounced in oncology trials. We present results of a structured concept-development phase (CDP) for a phase III RCT on personalized radiotherapy (RT) in primary prostate cancer (PCa) patients implementing prostate specific membrane antigen targeting positron emission tomography (PSMA-PET).

Materials and methods

The 1 yr process of the CDP contained five main working packages: (i) literature search and scoping review, (ii) involvement of individual patients, patients’ representatives and patients’ self-help groups addressing the patients’ willingness to participate in the preparation process and the conduct of RCTs as well as the patient informed consent (PIC), (iii) involvement of national and international experts and expert panels (iv) a phase II pilot study investigating the safety of implementation of PSMA-PET for focal dose escalation RT and (v) in-silico RT planning studies assessing feasibility of envisaged dose regimens and effects of urethral sparing in focal dose escalation.

Results

(i) Systematic literature searches confirmed the high clinical relevance for more evidence on advanced RT approaches, in particular stereotactic body RT, in high-risk PCa patients. (ii) Involvement of patients, patient representatives and randomly selected males relevantly changed the PIC and initiated a patient empowerment project for training of bladder preparation. (iii) Discussion with national and international experts led to adaptions of inclusion and exclusion criteria. (iv) Fifty patients were treated in the pilot trial and in- and exclusion criteria as well as enrollment calculations were adapted accordingly. Parallel conduction of the pilot trial revealed pitfalls on practicability and broadened the horizon for translational projects. (v) In-silico planning studies confirmed feasibility of envisaged dose prescription. Despite large prostate- and boost-volumes of up to 66% of the prostate, adherence to stringent anorectal dose constraints was feasible. Urethral sparing increased the therapeutic ratio.

Conclusion

The dynamic framework of interdisciplinary working programs in CDPs enhances robustness of RCT protocols and may be associated with decreased failure rates. Structured recommendations are warranted to further define the process of such CDPs in radiation oncology trials.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09434-2.

Long-Term Outcomes of Dose-Escalated Hypofractionated Radiotherapy in Localized Prostate Cancer

This retrospective study aimed to provide some clinical outcomes regarding effectiveness, toxicity, and quality of life in PCa patients treated with dose-escalated moderately hypofractionated radiation therapy (HFRT). Patients received HFRT to a total dose of 66 Gy in 22 fractions (3 Gy/fraction) delivered via volume modulated arc therapy (VMAT) in 2011-2016. Treatment effectiveness was measured by the biochemical failure-free survival rate. Toxicity was assessed according to the criteria of the Radiation Therapy Oncology Group (RTOG) and quality of life according to the criteria of the European Organization for Research and Treatment of Cancer (EORTC). In this regard, quality of life (QoL) was measured longitudinally, at a median of 2 and 5 years after RT. Enrolled patients had low-risk (40.2%), intermediate-risk (47.5%), and high-risk (12.3%) PCa. Median follow-up was 75 months. The biochemical failure-free survival rate was 94.2%. The incidence of acute grade 2 or higher gastrointestinal (GI) and genitourinary (GU) toxicity was 9.84% and 28.69%, respectively. The incidence rate of late grade 2 or higher GI and GU toxicity was 1.64% and 4.10%, respectively. Expanded Prostate Cancer Index Composite (EPIC) scores showed that the majority of patients maintained their QoL. HFRT to 66 Gy with VMAT was associated with adequate biochemical control, low toxicity and good reported GU and GI quality of life.

Patient-Reported Quality of Life Outcomes after Moderately Hypofractionated and Normofractionated Proton Therapy for Localized Prostate Cancer

We retrospectively evaluated the three-year patient-reported quality of life (QOL) after moderately hypofractionated proton therapy (MHPT) for localized prostate cancer in comparison with that after normofractionated PT (NFPT) using the Expanded Prostate Cancer Index Composite-50. Patients who received MHPT (60-63 Gy (relative biological effectiveness equivalents; RBE)/20-21 fractions) (n = 343) or NFPT (74-78 Gy (RBE)/37-39 fractions) (n = 296) between 2013 and 2016 were analyzed. The minimum clinically important difference (MCID) threshold was defined as one-half of a standard deviation of the baseline value. The median follow-up was 56 months and 83% completed questionnaires at 36 months. Clinically meaningful score deterioration was observed in the urinary domain at 1 month in both groups and in the sexual domain at 6-36 months in the NFPT group, but not observed in the bowel domain. At 36 months, the mean score change for urinary summary was -0.3 (MHPT) and -1.6 points (NFPT), and that for bowel summary was +0.1 and -2.0 points; the proportion of patients with MCID was 21% and 24% for urinary summary and 18% and 29% for bowel summary. Overall, MHPT had small negative impacts on QOL over three years, and the QOL after MHPT and NFPT was similar.

External radiotherapy for prostatic cancers

We present the update of the recommendations of the French society of oncological radiotherapy on external radiotherapy of prostate cancer. External radiotherapy is intended for all localized prostate cancers, and more recently for oligometastatic prostate cancers. The irradiation techniques are detailed. Intensity-modulated radiotherapy combined with prostate image-guided radiotherapy is the recommended technique. A total dose of 74 to 80Gy is recommended in case of standard fractionation (2Gy per fraction). Moderate hypofractionation (total dose of 60Gy at a rate of 3Gy per fraction over 4 weeks) in the prostate has become a standard of therapy. Simultaneous integrated boost techniques can be used to treat lymph node areas. Extreme hypofractionation (35 to 40Gy in five fractions) using stereotactic body radiotherapy can be considered a therapeutic option to treat exclusively the prostate. The postoperative irradiation technique, indicated mainly in case of biological recurrence and lymph node involvement, is detailed.

Impact of Hypofractionated Radiotherapy on Patient-reported Outcomes in Prostate Cancer: Results up to 5 yr in the CHHiP trial (CRUK/06/016)

BACKGROUND

Moderate hypofractionation is the recommended standard of care for localised prostate cancer following the results of trials including Conventional or Hypofractionated High Dose Intensity Modulated Radiotherapy in Prostate Cancer (CHHiP). Evaluation of long-term patient-reported outcomes (PROs) is important to confirm safety and enhance patient information.

OBJECTIVE

To determine whether 5-yr PROs from the CHHiP quality of life (QoL) substudy confirm 2-yr findings and assess patterns over follow-up.

DESIGN, SETTING, AND PARTICIPANTS

A phase III randomised controlled trial recruited from 2002 to 2011. The QoL substudy completed accrual in 2009; participants were followed up to 5 yr after radiotherapy. Analyses used data snapshot taken on August 26, 2016. A total of 71 radiotherapy centres were included in the study (UK, Republic of Ireland, Switzerland, and New Zealand); all 57 UK centres participated in the QoL substudy. CHHiP recruited 3216 men with localised prostate cancer (cT1b-T3aN0M0).

INTERVENTION

Conventional (74 Gy/37 fractions/7.4 wk) or hypofractionated radiotherapy (60 Gy/20 fractions/4 wk or 57 Gy/19 fractions/3.8 wk) was delivered with intensity-modulated techniques.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

University of California Los Angeles Prostate Cancer Index, Short Form 36 and Functional Assessment of Cancer Therapy-Prostate, or Expanded Prostate Cancer Index Composite and Short Form 12 questionnaires were administered at baseline, before radiotherapy, at 10 wk, and at 6, 12, 18, 24, 36, 48, and 60 mo after radiotherapy. The QoL primary endpoint was overall bowel bother.

RESULTS AND LIMITATIONS

The QoL substudy recruited 2100 patients; 1141 5-yr forms were available from 1957 patients still alive (58%). There were no statistically significant differences in 5-yr prevalence of overall "moderate or big" bowel bother: 19/349 (5.4%), 29/381 (7.6%), and 21/393 (5.3%) for 74, 60, and 57 Gy, respectively; overall urinary or sexual bother at 5 yr was similar between schedules. Bowel and urinary symptoms remained stable from 2 to 5 yr for all schedules. Some evidence of worsening overall sexual bother from baseline to 5 yr was less likely in the hypofractionated schedules compared with 74 Gy (odds ratios for increase in bother score vs 74 Gy: 0.55 [0.30-0.99], p = 0.009 for 60 Gy, and 0.52 [0.29-0.94], p = 0.004 for 57 Gy). General QoL scores were similar between schedules at 5 yr.

CONCLUSIONS

Longer follow-up confirms earlier findings, with similar patient-reported bowel, urinary, and sexual problems between schedules overall. The continued low incidence of moderate or high bother confirms that moderate hypofractionation should be the standard of care for intermediate-risk localised prostate cancer.

PATIENT SUMMARY

We looked at patient-reported outcomes up to 5 yr after treatment in a trial of different radiotherapy schedules for prostate cancer. The findings confirmed that shorter radiotherapy schedules were as safe as standard radiotherapy in terms of bowel, urinary, and sexual problems. TAKE  HOME MESSAGE: Bowel, urinary, and sexual symptoms were similar between schedules up to 5 yr. The continued low incidence of moderate/high bother confirms that moderate hypofractionated radiotherapy should be considered the standard of care for men with intermediate-risk prostate cancer.

PSMA-PET/MRI-Based Focal Dose Escalation in Patients with Primary Prostate Cancer Treated with Stereotactic Body Radiation Therapy (HypoFocal-SBRT): Study Protocol of a Randomized, Multicentric Phase III Trial

Technical advances in radiotherapy (RT) treatment planning and delivery have substantially changed RT concepts for primary prostate cancer (PCa) by (i) enabling a reduction of treatment time, and by (ii) enabling safe delivery of high RT doses. Several studies proposed a dose-response relationship for patients with primary PCa and especially in patients with high-risk features, as dose escalation leads to improved tumor control. In parallel to the improvements in RT techniques, diagnostic imaging techniques like multiparametric magnetic resonance imaging (mpMRI) and positron-emission tomography targeting prostate-specific-membrane antigen (PSMA-PET) evolved and enable an accurate depiction of the intraprostatic tumor mass for the first time. The HypoFocal-SBRT study combines ultra-hypofractionated RT/stereotactic body RT, with focal RT dose escalation on intraprostatic tumor sides by applying state of the art diagnostic imaging and most modern RT concepts. This novel strategy will be compared with moderate hypofractionated RT (MHRT), one option for the curative primary treatment of PCa, which has been proven by several prospective trials and is recommended and carried out worldwide. We suspect an increase in relapse-free survival (RFS), and we will assess quality of life in order to detect potential changes.

Hypofractionated radiotherapy recommendations for localized prostate cancer in Brasil

OBJECTIVE

Several prospective randomized trials have shown that hypofractionation has the same efficacy and safety as the conventional fractionation in the treatment of localized prostate cancer. There are many benefits of hypofractionation, including a more convenient schedule for the patients and better use of resources, which is especially important in low- and middle-income countries like Brasil. Based on these data, the Brazilian Society of Radiotherapy (Sociedade Brasileira de Radioterapia) organized this consensus to guide and support the use of hypofractionated radiotherapy for localized prostate cancer in Brasil.

METHODS

The relevant literature regarding moderate hypofractionation (mHypo) and ultra-hypofractionation (uHypo) was reviewed and discussed by a group of experts from public and private centers of different parts of Brasil. Several key questions concerning clinical indications, outcomes and technological requirements for hypofractionation were discussed and voted. For each question, consensus was reached if there was an agreement of at least 75% of the panel members.

RESULTS

The recommendations are described in this article.

CONCLUSION

This initiative will assist Brazilian radiation oncologists and medical physicists to safely treat localized prostate cancer patients with hypofractionation.

Optimizing External Beam Radiotherapy as per the Risk Group of Localized Prostate Cancer: A Nationwide Multi-Institutional Study (KROG 18-15)

Simple Summary

This multi-institutional study analyzed the patterns of care and outcomes of external beam radiotherapy (EBRT) in localized prostate cancer to identify the optimal EBRT strategy for each risk-stratified patient subgroup for clinical practice implementation. In 1573 patients from 17 institutions, EBRT treated prostate cancer effectively. Also, among various risk classification tools, NCCN classification revealed the highest predictive power. The modern RT techniques and dose escalation (≥179 Gy_1.5) enhanced therapeutic effects of RT significantly, especially in the high-risk group. On the other hand, modest doses (≥170 Gy_1.5) was a significant factor in the intermediate-risk group and no significant impact of dose was observed in the low-risk group. IMRT+ ≥179 Gy_1.5+ hypofractionation resulted in higher biochemical failure-free survival in all risk groups, and it translated into survival benefits in the high-risk group. Therefore, risk-adapted RT (more intense RT, high-risk patients; moderate-dose RT, low-risk patients) can be considered, although further prospective studies are warranted.

Abstract

Purpose: This nationwide multi-institutional study analyzed the patterns of care and outcomes of external beam radiotherapy (EBRT) in localized prostate cancer patients. We compared various risk classification tools and assessed the need for refinements in current radiotherapy (RT) schemes. Methods and Materials: We included non-metastatic prostate cancer patients treated with primary EBRT from 2001 to 2015 in this study. Data of 1573 patients from 17 institutions were analyzed and re-grouped using a risk stratification tool with the highest predictive power for biochemical failure-free survival (BCFFS). We evaluated BCFFS, overall survival (OS), and toxicity rates. Results: With a median follow-up of 75 months, 5- and 10-year BCFFS rates were 82% and 60%, and 5- and 10-year OS rates were 95% and 83%, respectively. NCCN risk classification revealed the highest predictive power (AUC = 0.556, 95% CI 0.524–0.588; p < 0.001). Gleason score, iPSA < 12 ng/mL, intensity-modulated RT (IMRT), and ≥179 Gy_1.5 (EQD2, 77 Gy) were independently significant for BCFFS (all p < 0.05). IMRT and ≥179 Gy_1.5 were significant factors in the high-risk group, whereas ≥170 Gy_1.5 (EQD2, 72 Gy) was significant in the intermediate-risk group and no significant impact of dose was observed in the low-risk group. Both BCFFS and OS improved significantly when ≥179 Gy_1.5 was delivered using IMRT and hypofractionation in the high-risk group without increasing toxicities. Conclusions: With NCCN risk classification, dose escalation with modern high-precision techniques might increase survivals in the high-risk group, but not in the low-risk group, although mature results of prospective studies are awaited.

Comparative effectiveness of robotic and open radical prostatectomy

Radical prostatectomy (RP) has undergone a remarkable transformation from open to minimally-invasive surgery over the last two decades. However, it is important to recognize there is still conflicting evidence regarding key outcomes. We aimed to summarize current literature on comparative effectiveness of robotic and open RP for key outcomes including oncologic results, health-related quality of life (HRQOL) measures, safety and postoperative complications, and healthcare costs. The bulk of the paper will discuss and interpret limitations of current data. Finally, we will also highlight future directions of both surgical approaches and its potential impact on health care delivery.

Mapping expanded prostate cancer index composite to EQ5D utilities to inform economic evaluations in prostate cancer: Secondary analysis of NRG/RTOG 0415

PURPOSE

The Expanded Prostate Cancer Index Composite (EPIC) is the most commonly used patient reported outcome (PRO) tool in prostate cancer (PC) clinical trials, but health utilities associated with the different health states assessed with this tool are unknown, limiting our ability to perform cost-utility analyses. This study aimed to map EPIC tool to EuroQoL-5D-3L (EQ5D) to generate EQ5D health utilities.

METHODS AND MATERIALS

This is a secondary analysis of a prospective, randomized non-inferiority clinical trial, conducted between 04/2006 and 12/2009 at cancer centers across the United States, Canada, and Switzerland. Eligible patients included men >18 years with a known diagnosis of low-risk PC. Patient HRQoL data were collected using EPIC and health utilities were obtained using EQ5D. Data were divided into an estimation sample (n = 765, 70%) and a validation sample (n = 327, 30%). The mapping algorithms that capture the relationship between the instruments were estimated using ordinary least squares (OLS), Tobit, and two-part models. Five-fold cross-validation (in-sample) was used to compare the predictive performance of the estimated models. Final models were selected based on root mean square error (RMSE).

RESULTS

A total of 565 patients in the estimation sample had complete information on both EPIC and EQ5D questionnaires at baseline. Mean observed EQ5D utility was 0.90±0.13 (range: 0.28-1) with 55% of patients in full health. OLS models outperformed their counterpart Tobit and two-part models for all pre-determined model specifications. The best model fit was: "EQ5D utility = 0.248541 + 0.000748*(Urinary Function) + 0.001134*(Urinary Bother) + 0.000968*(Hormonal Function) + 0.004404*(Hormonal Bother)- 0.376487*(Zubrod) + 0.003562*(Urinary Function*Zubrod)"; RMSE was 0.10462.

CONCLUSIONS

This is the first study to identify a comprehensive set of mapping algorithms to generate EQ5D utilities from EPIC domain/ sub-domain scores. The study results will help estimate quality-adjusted life-years in PC economic evaluations.

Analysis of Patient-Reported Outcome Utilization Within National Clinical Trials Network Cooperative Group Radiation Oncology Trials Over the Past 2 Decades

PURPOSE

When treating cancer, both quantity and quality of life are valuable, though oncology trials have long placed greater emphasis on the former. The goal of this work was to evaluate how patient-reported outcomes (PROs) have been incorporated into radiation therapy trials within the National Clinical Trials Network over the last 2 decades to measure quality of life and to assess how PRO data have been disseminated in publications upon trial conclusion.

METHODS AND MATERIALS

This cross-sectional study analyzed the frequency of use of PROs in National Clinical Trials Network cooperative group radiation therapy phase 2 and 3 clinical trials over the past 2 decades. A literature review was performed to determine the publication outcomes of PRO data, including only trials that used PROs in their design and were mature enough to have published results.

RESULTS

Fifty-seven (56.4%) of the 101 trials included in this study included PROs in their design. Brain and head and neck trials demonstrated the largest proportional incorporation of PROs (81.8% and 76.9%, respectively), and thoracic and breast trials used the fewest (18.8% and 37.5%, respectively). The EQ-5D family of questionnaires was the most commonly used PROs, used in 22.8% of trials included. The literature review demonstrated a pattern of increased publication of PRO data alongside survival endpoints in manuscripts derived from these trials over time.

CONCLUSIONS

Though there is room for improvement, the field of radiation oncology has embraced the incorporation of PROs into multicenter, high-impact clinical trials over the past 2 decades and has increased its publication of this data alongside survival data from these trials.

Hypofractionated versus conventionally fractionated image-guided volumetric-modulated arc radiotherapy for localized prostate cancer: a phase II randomized trial from China

Purpose: To determine the safety of hypofractionated imaging-guided (IG) volumetric-modulated arc radiotherapy (IG-VMAT; 70 Gy/28 fractions over 5.5 weeks) versus conventionally fractionated regimen (IG-VMAT; 80 Gy/40 fractions over 8 weeks) in Chinese patients with localized prostate cancer.

Method: In this randomized non-comparative phase II trial, 92 patients with localized prostate cancer were assigned to receive either hypofractionated IG-VMAT (HFRT; 70 Gy/2.5Gy/28f) or conventionally fractionated IG-VMAT (CFRT; 80 Gy/2Gy/40f). Primary endpoint was grade 2 or higher late gastrointestinal (GI) and genitourinary (GU) toxicity at 2 years. The GI/GU toxicity and biochemical relapse–free survival (bRFS) were compared between the two treatment groups.

Results: Median follow-up was 26 months. The incidence of grade 2 or higher late GI/GU toxicity was low in both groups; the 5-year cumulative incidence of Radiation Therapy Oncology Group grade 2 or higher GI/GU toxicity at 2 years was 7.6% with HFRT versus 10.3% with CFRT (P = 0.707). Biochemical control was not significantly different between the two groups; the 2-year bRFS was 94.6% for HFRT versus 95.0% for CFRT (P = 0.704).

Conclusion: Hypofractionated IG-VMAT appears to be equivalent to conventionally fractionated IG-VMAT in terms of toxicity in Chinese patients with localized prostate cancer.

Comparing bowel and urinary domains of patient-reported quality of life at the end of and 3 months post radiotherapy between intensity-modulated radiotherapy and proton beam therapy for clinically localized prostate cancer

PURPOSE

To prospectively assess acute differences in patient-reported outcomes in bowel and urinary domains between intensity-modulated radiotherapy (IMRT) and proton beam therapy (PBT) for prostate cancer.

METHODS AND MATERIALS

Bowel function (BF), urinary irritative/obstructive symptoms (UO), and urinary incontinence (UI) domains of EPIC-26 were collected in patients with T1-T2 prostate cancer receiving IMRT or PBT at a tertiary cancer center (2015-2018). Mean changes in domain scores were analyzed from pretreatment to the end of and 3 months post-radiotherapy for each modality. A clinically meaningful change was defined as a score change >50% of the baseline standard deviation.

RESULTS

A total of 157 patients receiving IMRT and 105 receiving PBT were included. There were no baseline differences in domain scores between cohorts. At the end of radiotherapy, there was significant and clinically meaningful worsening of BF and UO scores for patients receiving either modality. In the BF domain, the IMRT cohort experienced greater decrement (-13.0 vs -6.7, P < .01), and had a higher proportion of patients with clinically meaningful reduction (58.4% vs 39.5%, P = .01), compared to PBT. At 3 months post-radiotherapy, the IMRT group had significant and clinically meaningful worsening of BF (-9.3, P < .001), whereas the change in BF score of the PBT cohort was no longer significant or clinically meaningful (-1.2, P = .25). There were no significant or clinically meaningful changes in UO or UI 3 months post-radiotherapy.

CONCLUSIONS

PBT had less acute decrement in BF than IMRT following radiotherapy. There was no difference between the two modalities in UO and UI.

Moderately Hypofractionated Intensity Modulated Radiation Therapy With Simultaneous Integrated Boost for Prostate Cancer: Five-Year Toxicity Results From a Prospective Phase I/II Trial

BACKGROUND

In this phase I/II trial, 5-year physician-assessed toxicity and patient reported quality of life data is reported for patients undergoing moderately hypofractionated intensity modulated radiation therapy (IMRT) for prostate cancer using a simultaneous integrated boost (SIB) and pelvic lymph node (LN) coverage.

MATERIALS AND METHODS

Patients with T1-T2 localized prostate cancer were prospectively enrolled, receiving risk group based coverage of prostate ± seminal vesicles (SVs) ± pelvic lymph nodes (LNs). Low risk (LR) received 69.6 Gy/29 fractions to the prostate, while intermediate risk (IR) and high risk (HR) patients received 72 Gy/30fx to the prostate and 54Gy/30fx to the SVs. If predicted risk of LN involvement >15%, 50.4 Gy/30fx was delivered to pelvic LNs. Androgen deprivation therapy was given to IR and HR patients.

RESULTS

There were 55 patients enrolled and 49 patients evaluable at a median follow up of 60 months. Included were 11 (20%) LR, 23 (41.8%) IR, and 21 (38.2%) HR patients. Pelvic LN treatment was given in 25 patients (51%). Prevalence rates of late grade 2 GI toxicity at 1, 3, and 5 years was 5.8, 3.9, and 5.8%, respectively, with no permanent grade 3 events. Prevalence rates of late grade 2 GU toxicity at 1, 3, and 5 years rates were 15.4, 7.7, and 13.5%, respectively, with three grade 3 events (5.8%). The biochemical relapse free survival at 5 years was 88.3%. There were no local, regional, or distant failures, with all patients still alive at last follow up.

CONCLUSION

Moderate hypofractionation of localized prostate cancer utilizing a SIB technique and LN coverage produces tolerable acute/late toxicity. Given equivalent efficacy between moderate hypofractionation schedules, the optimal regimen will be determined by long-term toxicity reported from both the physician and patient perspective.

CLINICAL TRIAL REGISTRATION

www.ClinicalTrials.gov, identifier NCT01117935, Date of Registration: 5/6/2010.

Translating the Immunobiology of SBRT to Novel Therapeutic Combinations for Advanced Prostate Cancer

Stereotactic body radiotherapy (SBRT) is an increasingly used radiation modality for the treatment of both localized and metastatic prostate cancer. Substantial data suggests that prostate cancer may be more sensitive to higher doses of radiation per fraction due to its low α/β ratio. This increased sensitivity raises important questions as to how SBRT should be combined with systemic therapy for clinically significant prostate cancer, including whether androgen deprivation therapy retains its beneficial effects when combined with SBRT. Furthermore, pre-clinical and clinical data suggest pronounced immunomodulatory effects of SBRT, including observed improvements in T cell priming and trafficking. These data support investigational strategies combining SBRT with immunotherapy. Here we aim to review the data for the use of SBRT in both the local and metastatic disease settings as well as ongoing translational and clinical research examining combinations with ADT, immunotherapy and other targeted agents.

Erectile Dysfunction and Absorbed Dose to Penile Base Structures in a Randomized Trial Comparing Ultrahypofractionated and Conventionally Fractionated Radiation Therapy for Prostate Cancer

PURPOSE

To study the relationships between absorbed dose to penile base structures and erectile dysfunction (ED) in patients treated with ultrahypofractionated (UHF) radiation therapy (RT) or conventionally fractionated (CF) RT for prostate cancer.

METHODS AND MATERIALS

This dose-response study comprises 673 patients (57%) of the 1180 per-protocol patients included in the HYPO-RT-PC trial (median follow-up 5, years), where patients were randomized to CF (39 × 2.0 Gy, 8 weeks) or UHF (7 × 6.1 Gy, 2.5 weeks). No androgen deprivation therapy was allowed. Only patients with erectile function sufficient for intercourse at baseline and complete RT data were included in this study. Erectile function was assessed by physician at regular follow-ups. The main endpoint was severe ED (ED_s). The penile bulb (PB) and crus were retrospectively delineated on the treatment planning computed tomography scans. Dose-volume descriptors were derived from EQD2 converted dose matrices (α/β = 3 Gy). Univariable and multivariable Cox proportional hazard regression and logistic regression were used to find predictors for ED_S.

RESULTS

No significant difference in ED_s was found between CF and UHF. During the follow-up period, ED_s occurred in 27% of the patients in both treatment groups. Average (median) PB mean dose, D_mean, was 24.5 (20.2) in CF and 18.7 (13.1) Gy₃ in UHF. Age was the only significant predictor for ED_s in Cox analyses. All dose-volume variables contributed significantly in univariable logistic regression at 2-year follow-up. Age and near maximum dose (D_2%) were significant predictors for ED_s in multivariable logistic regression analyses at both 1 and 2 years.

CONCLUSIONS

The frequency of ED_S was similar in the CF and UHF treatment groups. Age at radiation therapy was the strongest predictor for ED_s, followed by dose to PB, and was most evident for younger patients. We propose D_{2 %} <50 Gy₃ and D_mean <20 Gy₃ to the PB as the primary objectives to be applied in the treatment planning process.

Patient-Reported Functional Outcomes After Hypofractionated or Conventionally Fractionated Radiation for Prostate Cancer: A National Cohort Study in England

PURPOSE

The aim of the current study was to determine patient-reported functional outcomes in men with prostate cancer (PCa) undergoing moderately hypofractionated (H-RT) or conventionally fractionated radiation therapy (C-RT) in a national cohort study.

PATIENDS AND METHODS

All men diagnosed with PCa between April 2014 and September 2016 in the English National Health Service undergoing C-RT or H-RT were identified in the National Prostate Cancer Audit and mailed a questionnaire at least 18 months after diagnosis. We estimated differences in patient-reported urinary, bowel, sexual, and hormonal function-Expanded Prostate Cancer Index Composite short-form 26 domain scores on a 0 to 100 scale-and health-related quality of life-EQ-5D-5L on a 0 to 1 scale-using linear regression with adjustment for patient, tumor, and treatment-related factors in addition to GI and genitourinary baseline function, with higher scores representing better outcomes.

RESULTS

Of the 17,058 men in the cohort, 77% responded: 8,432 men received C-RT (64.2%) and 4,699 H-RT (35.8%). Men in the H-RT group were older (age ≥ 70 years: 67.5% v 60.9%), fewer men had locally advanced disease (56.5% v 71.3%), were less likely to receive androgen-deprivation therapy (79.5% v 87.8%), and slightly more men had pretreatment genitourinary procedures (24.2% v 21.2%). H-RT was associated with small increases in adjusted mean Expanded Prostate Cancer Index Composite short-form 26 sexual (3.3 points; 95% CI, 2.1 to 4.5; P < .001) and hormonal function scores (3.2 points; 95% CI, 1.8 to 4.6; P < .001). These differences failed to meet established thresholds for a clinically meaningful change. There were no statistically significant differences in urinary or bowel function and quality of life.

CONCLUSION

This is the first national cohort study comparing functional outcomes after H-RT and C-RT reported by patients. These real-world results further support the use of H-RT as the standard for radiation therapy in men with nonmetastatic PCa.

Hypofractionated radiotherapy versus conventional radiotherapy in patients with intermediate- to high-risk localized prostate cancer: a meta-analysis of randomized controlled trials

Background

Prostate cancer is one of the most common cancers in the world. The results of treatment after hypofractionated radiotherapy only have been reported from several small randomized clinical trials. Therefore, we conducted a meta-analysis to compare clinical outcomes of hypofractionated radiotherapy versus conventional radiotherapy in the treatment of intermediate- to high-risk localized prostate cancer.

Methods

Relevant studies were identified through searching related databases till August 2018. Hazard ratio (HR) or risk ratio (RR) with its corresponding 95% confidence interval (CI) was used as pooled statistics for all analyses.

Results

The meta-analysis results showed that overall survival (HR = 1.12, 95% CI: 0.93–1.35, p = 0.219) and prostate cancer-specific survival (HR = 1.29, 95% CI: 0.42–3.95, p = 0.661) were similar in two groups. The pooled data showed that biochemical failure was RR = 0.90, 95% CI: 0.76–1.07, p = 0.248. The incidence of acute adverse gastrointestinal events (grade ≥ 2) was higher in the hypofractionated radiotherapy (RR = 1.70, 95% CI: 1.12–2.56, p = 0.012); conversely, for late grade ≥ 2 gastrointestinal adverse events, a significant increase in the conventional radiotherapy was found (RR = 0.75, 95% CI: 0.61–0.91, p = 0.003). Acute (RR = 1.01, 95% CI: 0.89–1.15, p = 0.894) and late (RR = 0.98, 95% CI: 0.86–1.10, p = 0.692) genitourinary adverse events (grade ≥ 2) were similar for both treatment groups.

Conclusion

Results suggest that the efficacy and risk for adverse events are comparable for hypofractionated radiotherapy and conventional radiotherapy in the treatment of intermediate- to high-risk localized prostate cancer.