The Effectiveness of Intensity Modulated Radiation Therapy versus Three-Dimensional Radiation Therapy in Prostate Cancer: A Meta-Analysis of the Literatures

Clinical and functional outcomes for risk-appropriate treatments for prostate cancer

Objectives

To describe real-world clinical and functional outcomes in an Australian cohort of men with localised prostate cancer according to treatment type and risk category.

Subjects and methods

Men diagnosed from 2008 to 2018 who were enrolled in South Australian Prostate Cancer Clinical Outcomes Collaborative registry-a multi-institutional prospective clinical registry-were studied. The main outcome measures were overall survival, cancer-specific survival, decline in functional outcomes, biochemical recurrence and transition to active treatment following active surveillance. Multivariable adjusted models were applied to estimate outcomes.

Results

Of the 8513 eligible men, majority of men (46%) underwent radical prostatectomy (RP) followed by external beam radiation therapy with or without androgen deprivation therapy (EBRT +/- ADT) in 22% of the cohort. Five-year overall survival was above 91%, and 5-year prostate cancer-specific survival was above 97% in the low- and intermediate-risk categories across all treatments. Five-year prostate cancer-specific survival in the active surveillance group was 100%. About 37% of men with high-risk disease treated with RP and 17% of men treated with EBRT +/- ADT experienced biochemical recurrence within 5 years of treatment. Of men on active surveillance, 15% of those with low risk and 20% with intermediate risk converted to active treatment within 2 years. The decline in urinary continence and sexual function 12 months after treatment was greatest among men who underwent RP while the decline in bowel function was greatest for men who received EBRT +/- ADT.

Conclusion

This contemporary real-world evidence on risk-appropriate treatment outcomes helps inform treatment decision-making for clinicians and patients.

MRI-guided Pelvic Radiation Therapy: A Primer for Radiologists

Radiation therapy (RT) is a core pillar of oncologic treatment, and half of all patients with cancer receive this therapy as a curative or palliative treatment. The recent integration of MRI into the RT workflow has led to the advent of MRI-guided RT (MRIgRT). Using MRI rather than CT has clear advantages for guiding RT to pelvic tumors, including superior soft-tissue contrast, improved organ motion visualization, and the potential to image tumor phenotypic characteristics to identify the most aggressive or treatment-resistant areas, which can be targeted with a more focal higher radiation dose. Radiologists should be familiar with the potential uses of MRI in planning pelvic RT; the various RT techniques used, such as brachytherapy and external beam RT; and the impact of MRIgRT on treatment paradigms. Current clinical experience with and the evidence base for MRIgRT in the settings of prostate, cervical, and bladder cancer are discussed, and examples of treated cases are illustrated. In addition, the benefits of MRIgRT, such as real-time online adaptation of RT (during treatment) and interfraction and/or intrafraction adaptation to organ motion, as well as how MRIgRT can decrease toxic effects and improve oncologic outcomes, are highlighted. MRIgRT is particularly beneficial for treating mobile pelvic structures, and real-time adaptive RT for tumors can be achieved by using advanced MRI-guided linear accelerator systems to spare organs at risk. Future opportunities for development of biologically driven adapted RT with use of functional MRI sequences and radiogenomic approaches also are outlined. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Gastrointestinal/genitourinary adverse event after intensity modulated versus three-dimensional primary radiation therapy in the treatment of prostate cancer: systematic review and meta-analysis

Objective: Prostate cancer (PCa) is one of the most common cancers in the world. The potential benefits of intensity modulated radiation therapy (IMRT) over three-dimensional conformal radiation therapy (3D-CRT) for PCa primary radiation therapy treatment have not yet been clarified. Therefore, this meta-analysis was conducted to assess whether IMRT could improve clinical outcomes in comparison with 3D-CRT in patients diagnosed with PCa. Materials and methods: Relevant studies were identified through searching related databases till December, 2022. Hazard ratio (HR) or risk ratio (RR) with its corresponding 95% confidence interval (CI) was used as pooled statistics for all analyses. Results: The incidence of grade 2 or worse acute adverse gastrointestinal (GI) event was analyzed and the pooled data revealed a clear decreasing trend in the IMRT compared with 3D-CRT (RR=0.62, 95% CI: 0.45-0.84, p=0.002). IMRT slightly increased the grade ≥ 2 acute genitourinary (GU) adverse event in comparison with the 3D-CRT (RR=1.10, 95% CI: 1.02-1.19, p=0.015). The IMRT and the 3D-CRT of patients showed no substantial differences in grade ≥ 2 late GI adverse event (RR =0.62, 95% CI: 0.36-1.09, p=0.1). In those included studies, there was no significant difference between IMRT and 3D-CRT in grade 2-4 late GU adverse event (RR =1.08, 95% CI: 0.77-1.51, p=0.65). There was a significant difference in biochemical control favoring IMRT (RR =1.13, 95% CI: 1.05-1.22, p=0.002). IMRT showed modest increase in biochemical control in comparison with 3D-CRT. Conclusion: In general, based on the above results, IMRT should be considered as a better choice for the treatment of PCa. More randomized controlled trials are needed to determine the subset of patients diagnosed with PCa.

Effects of surgery versus radiotherapy in patients with localized prostate cancer in terms of urinary, bowel, and sexual domains

BACKGROUND

The health-related quality of life (HRQoL) of patients with localized prostate cancer (LPCa) after treatment mainly surgery and radiotherapy (RT) has received increasing attention. The aim of this study is to compare the HRQoL of LPCa after surgery and RT.

METHODS

Web of Science, Embase, PubMed and Cochrane databases were searched after January 2000 to observe the HRQoL scores after surgery and RT at different treatment time points.

RESULTS

A total of 28 studies were included in this study, and the results showed that LPCa received surgery had better bowel scores than RT at ≤3 (weighted mean differences [WMD] = 4.18; p = 0.03), 3-6 (WMD = 4.16; p < 0.001), 6-12 (WMD = 2.99; p = 0.004), 24-60 (WMD = 1.87; p = 0.06), and ≥60 (WMD = 4.54; p = 0.02) months. However, LPCa received RT had higher urinary scores at ≤3 (WMD = -7.39; p = 0.02), 3-6 (WMD = -6.03; p = 0.02), 6-12 (WMD = -4.90; p < 0.001), 24-60 (WMD = -3.96; p < 0.001), ≥60 (WMD = -2.95; p < 0.001) months and had better sexual scores at ≤3 (WMD = -13.58; p = 0.09), 3-6 (WMD = -12.32; p = 0.06), 6-12 (WMD = -12.03; p = 0.002), 24-60 (WMD = -11.29; p < 0.001), and ≥60 (WMD = -3.10; p = 0.46) months than surgery. The scores difference between surgery and RT decreased over time.

CONCLUSION

Overall, for LPCa, surgery was associated with better HRQoL in the bowel domain, whereas RT was associated with better HRQoL in the urinary and sexual domains, with the difference between surgery and RT narrowing over time.

Urinary Continence Recovery after Retzius-Sparing Robot Assisted Radical Prostatectomy and Adjuvant Radiation Therapy

Retzius-sparing robot-assisted radical prostatectomy (RS-RARP) allows the preservation of the structures advocated to play a crucial role in the continence mechanism. This study aims to evaluate the association between adjuvant radiation therapy (aRT) and urinary continence (UC) recovery after RS-RARP. For the purpose of the current study, all patients submitted to RS-RARP for prostate cancer (PCa) at a single high-volume European institution between January 2010 and December 2021 were identified. Only patients that harbored pT2 stage with positive surgical margins or pT3/pN1 stage with or without positive surgical margins were included in the analyses. Two groups of patients were identified as follows: patients who had undergone aRT and patients submitted to observation (no-aRT patients). As per definition, aRT was delivered within 1-6 months after surgery. After 1:1 propensity score matching, 124 aRT patients were compared with 124 no-aRT patients who continued standard follow-up protocol after surgery. UC recovery was 81 vs. 84% in aRT vs. no-aRT patients (p = 0.7). In multivariable Cox regression analyses, aRT did not reach the independent predictor status for UC recovery at 12 months. In the subgroup analysis including only aRT patients, only the nerve-sparing technique was independently associated with UC recovery at 12 months. Conversely, the type of aRT (IMRT/VMAT vs. 3D-CRT) did not reach the independent predictor status for UC recovery at 12 months. The current study is the first to address the association between aRT and UC recovery in patients treated with RS-RARP for PCa. Based on our data, aRT is not associated with worse UC recovery. In the cohort of patients treated with aRT, the nerve-sparing technique independently predicted UC recovery.

The Current Trend of Radiation Therapy for Patients with Localized Prostate Cancer

A recent approach to radiotherapy for prostate cancer is the administration of high doses of radiation to the prostate while minimizing the risk of side effects. Thus, image-guided radiotherapy utilizes advanced imaging techniques and is a feasible strategy for increasing the radiation dose. New radioactive particles are another approach to achieving high doses and safe procedures. Prostate brachytherapy is currently considered as a combination therapy. Spacers are useful to protect adjacent organs, specifically the rectum, from excessive radiation exposure.

Treatment-related toxicity using prostate bed versus prostate bed and pelvic lymph node radiation therapy following radical prostatectomy: A national population-based study

Purpose There is debate about the effectiveness and toxicity of pelvic lymph node (PLN) irradiation in addition to prostate bed radiotherapy when used to treat disease recurrence following radical prostatectomy. We compared toxicity from radiation therapy (RT) to the prostate bed and pelvic lymph nodes (PBPLN-RT) with prostatebed only radiation therapy (PBO-RT) following radical prostatectomy. Methods and Materials Patients with prostate cancer who underwent post-prostatectomy RT between 2010 and 2016 were identified by using the National Prostate Cancer Audit (NPCA) database. Follow-up data was available up to December 31, 2018. Validated outcome measures, based on a framework of procedural and diagnostic codes, were used to capture ≥Grade 2 gastrointestinal (GI) and genitourinary (GU) toxicity. An adjusted competing-risks regression analysis estimated subdistribution hazard ratios (sHR). A sHR > 1 indicated a higher incidence of toxicity with PBPLN-RT than with PBO-RT. Results 5-year cumulative incidences in the PBO-RT (n = 5,087) and PBPLNRT (n = 593) groups was 18.2% and 15.9% for GI toxicity, respectively. For GU toxicity it was 19.1% and 20.7%, respectively. There was no evidence of difference in GI or GU toxicity after adjustment between PBO-RT and PBPLN-RT (GI: adjusted sHR, 0.90, 95% CI, 0.67-1.19; P = 0.45); (GU: adjusted sHR, 1.19, 95% CI, 0.99-1.44; P = 0.09). Conclusions This national population-based study found that including PLNs in the radiation field following radical prostatectomy is not associated with a significant increase in rates of ≥Grade 2 GI or GU toxicity at 5 years.

Toxicity of dose-escalated radiotherapy up to 84 Gy for prostate cancer

PURPOSE

The outcome of radiotherapy (RT) for prostate cancer (PCA) depends on the delivered dose. While the evidence for dose-escalated RT up to 80 gray (Gy) is well established, there have been only few studies examining dose escalation above 80 Gy. We initiated the present study to assess the safety of dose escalation up to 84 Gy.

METHODS

In our retrospective analysis, we included patients who received dose-escalated RT for PCA at our institution between 2016 and 2021. We evaluated acute genitourinary (GU) and gastrointestinal (GI) toxicity as well as late GU and GI toxicity.

RESULTS

A total of 86 patients could be evaluated, of whom 24 patients had received 80 Gy and 62 patients 84 Gy (35 without pelvic and 27 with pelvic radiotherapy). Regarding acute toxicities, no > grade 2 adverse events occurred. Acute GU/GI toxicity of grade 2 occurred in 12.5%/12.5% of patients treated with 80 Gy, in 25.7%/14.3% of patients treated with 84 Gy to the prostate only, and in 51.9%/12.9% of patients treated with 84 Gy and the pelvis included. Late GU/GI toxicity of grade ≥ 2 occurred in 4.2%/8.3% of patients treated with 80 Gy, in 7.1%/3.6% of patients treated with 84 Gy prostate only, and in 18.2%/0% of patients treated with 84 Gy pelvis included (log-rank test p = 0.358).

CONCLUSION

We demonstrated that dose-escalated RT for PCA up to 84 Gy is feasible and safe without a significant increase in acute toxicity. Further follow-up is needed to assess late toxicity and survival.

Long term genitourinary toxicity following curative intent intensity-modulated radiotherapy for prostate cancer: a systematic review and meta-analysis

BACKGROUND

Recent studies have shown that radiation-induced pelvic toxicity often requires urological consultation. However, the 10-year incidence of genitourinary toxicity following intensity-modulated radiotherapy (IMRT) amongst patients with localised prostate cancer remains unclear. Hence, we conducted a systematic review and meta-analysis to determine the incidence of late genitourinary toxicity relying on Radiation Therapy Oncology Group (RTOG) and Common Terminology Criteria for Adverse Events (CTCAE) grade as well as the incidence of specific genitourinary toxicity. Secondary objectives involved quantifing the number of studies reporting 120-month follow-up endpoints, time to event analysis, predictive factors or economic evaluation.

METHODS

Articles published from January 2008 to December 2021 describing prospective studies were systematically searched in MEDLINE, EMBASE and Cochrane (PROSPERO protocol CRD42019133320). Quality assessment was performed by use of the Cochrane Risk of Bias 2 Tool for RCTs and the Newcastle Ottowa Scale for non-RCTs. Meta-analysis was performed on the 60-month incidence of RTOG and CTCAE Grade ≥2 genitourinary toxicity, haematuria, urinary retention and urinary incontinence.

RESULTS

We screened 4721 studies and six studies met our inclusion criteria. All included studies involved normofractionation, three included a hypofractionation comparator arm and none involved nodal irradiation. The pooled 60-month cumulative incidence of RTOG and CTCAE Grade ≥2 genitourinary toxicity were 17% (95% CI: 5-20%, n = 678) and 33% (95% CI: 27-38%, n = 153), respectively. The pooled 60-month cumulative incidence of Haematuria was 5% (95% CI: -4-14%, n = 48), Urinary incontinence 12% (95% CI: 6-18%, n = 194), Urinary retention 24% (95% CI: 9-40%, n = 10). One study reported time to event analyses, one reported predictive factors, no studies reported economic analysis or 120-month toxicity. There was considerable heterogeneity amongst the studies.

CONCLUSION

There are few high-quality studies reporting 60-month toxicity rates after IMRT. Conservative estimates of 60-month toxicity rates are high and there is need for longer follow-up and consistent toxicity reporting standards.

Effects of gold fiducial marker implantation on tumor control and toxicity in external beam radiotherapy of prostate cancer

BACKGROUND

Evidence regarding the effects of fiducials in image-guided radiotherapy (IGRT) for tumor control and acute and late toxicity is sparse.

PATIENTS AND METHODS

Patients with primary low- and intermediate-risk prostate cancer, 40 with and 21 without gold fiducial markers (GFM), and treated between 2010 and 2015 were retrospectively included. The decision for or against GFM implantation took anaesthetic evaluation and patient choice into account. IGRT was performed using electronic portal imaging devices. The prescribed dose was 78 Gy, with 2 Gy per fraction. Biochemical no evidence of disease (bNED) failure was defined using the Phoenix criteria. Acute and late gastrointestinal (GI) and genitourinary toxicity (GU) were assessed using the Radiation Therapy Oncology Group criteria.

RESULTS

Most patients did not receive GFM due to contraindications for anaesthesia or personal choice (60% and 25%). Regarding tumor control, no significant differences were found regarding bNED and overall and disease-specific survival (p = 0.61, p = 0.56, and p > 0.9999, respectively). No significant differences in acute and late GI (p = 0.16 and 0.64) and GU toxicity (p = 0.58 and 0.80) were observed.

CONCLUSIONS

We were unable to detect significant benefits in bNED or in early or late GI and GU side effects after GFM implantation.

Implementing online position monitoring for prostate radiotherapy using an in-house position monitoring system: User experience and impact on workforce

INTRODUCTION

To evaluate the feasibility of prostate intrafraction motion monitoring using the SeedTracker real-time image guidance system in order to improve targeting accuracy in prostate radiotherapy.

METHODS

SeedTracker was used to monitor prostate gold fiducial seeds with kV x-ray imaging during radiotherapy in 30 patients. Feedback from radiation therapists was collected via the use of a user evaluation form. The impact on treatment time was established by using a record and verify system. The effective dose and a risk of exposure-induced cancer death (REID) were estimated for a 60-year-old patient when using the SeedTracker system.

RESULTS

A total of 22 radiation therapists completed user evaluation forms. The time taken to prepare a reference data set for one patient varied with three (13.6%) radiation therapists taking less than 2 min, 10 (45.5%) between 2 and 4 min, eight (36.4%) between 4 and 6 min and one (4.5%) between 6 and 8 min. The useability of the SeedTracker system was reported as 'easy' by 21 (95.5%) radiation therapists and 'hard' by 1 (4.5%) radiation therapist. Mean treatment time changed from 6 to 7 min with prostate-only radiotherapy treatment and from 6.9 to 10.2 min with prostate and whole pelvis radiotherapy treatments. The maximum effective dose with the SeedTracker was 1.6276 mSv, and increase in REID was 0.007%.

CONCLUSION

The SeedTracker real-time image guidance system is a feasible tool to use in radiotherapy departments to monitor and correct for prostate intrafraction motion.

Patient-reported functional outcome measures and treatment choice for prostate cancer

Background

The aim of this study was to describe changes in patient-reported functional outcome measures (PROMs) comparing pre-treatment and 12 months after radical prostatectomy (RP), external beam radiation therapy (EBRT), brachytherapy and active surveillance (AS).

Methods

Men enrolled from 2010 to 2019 in the South Australian Prostate Cancer Clinical Outcomes Collaborative registry a prospective clinical registry were studied. Urinary, bowel, and sexual functions were measured using Expanded Prostate Cancer Index Composite (EPIC-26) at baseline and 12 months post-treatment. Higher scores on the EPIC-26 indicate better function. Multivariable regression models were applied to compare differences in function and extent of bother by treatment.

Results

Of the 4926 eligible men, 57.0% underwent RP, 20.5% EBRT, 7.0% brachytherapy and 15.5% AS. While baseline urinary and bowel function varied little across treatment groups, sexual function differed greatly (adjusted mean scores: RP = 56.3, EBRT = 45.8, brachytherapy = 61.4, AS = 52.8; p < 0.001). Post-treatment urinary continence and sexual function declined in all treatment groups, with the greatest decline for sexual function after RP (adjusted mean score change − 28.9). After adjustment for baseline differences, post-treatment sexual function scores after EBRT (6.4; 95%CI, 0.9–12.0) and brachytherapy (17.4; 95%CI, 9.4–25.5) were higher than after RP. Likewise, urinary continence after EBRT (13.6; 95%CI, 9.0-18.2), brachytherapy (10.6; 95%CI, 3.9–17.3) and AS (10.6; 95%CI, 5.9–15.3) were higher than after RP. Conversely, EBRT was associated with lower bowel function (− 7.9; 95%CI, − 12.4 to − 3.5) than RP. EBRT and AS were associated with lower odds of sexual bother (OR 0.51; 95%CI, 0.29–0.89 and OR 0.60; 95%CI, 0.38–0.96, respectively), and EBRT with higher odds of bowel bother (OR 2.01; 95%CI, 1.23–3.29) compared with RP.

Conclusion

The four common treatment approaches for prostate cancer were associated with different patterns of patient-reported functional outcomes, both pre- and 12 months post-treatment. However, after adjustment, RP was associated with a greater decline in urinary continence and sexual function than other treatments. This study underscores the importance of collecting baseline PROMs to interpret post-treatment functional outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-022-01117-1.

Advancements in the radiooncological treatment of high-risk prostate cancer: a quarter century of achievements

BACKGROUND

The aim of the study was to evaluate the development of treatment of primary high-risk prostate cancer in regards to biochemical no evidence of disease (bNED), acute and late gastrointestinal (GI) and genitourinary (GU) side effects.

PATIENTS AND METHODS

Primary high-risk prostate cancer patients treated between 1994 and 2016 were included. Applied doses ranged from 60 to 80 Gy, with a dose of 1.8 or 2 Gy per fraction. Techniques were either 3D conformal or intensity modulated radiotherapy and volumetric intensity modulated arc therapy.

RESULTS

142 patients were treated with doses up to 70 Gy (median dose 66 Gy; 66 Gy group), 282 with doses between 70 and 76 Gy (median dose 74 Gy; 74 Gy group), and 141 with doses >76 Gy (median dose 78 Gy; 78 Gy group). The median follow-up was 48 months. The bNED rates were 50% after 5 years and 44% after 9 years in the 66 Gy group; 65% and 54%, respectively, in the 74 Gy group; and 83% and 66%, respectively, in the 78 Gy group (p = 0.03 vs. 74 Gy and p < 0.0001 vs. 66 Gy). We found a higher rate of acute GI side effects in the 78 Gy group compared to the other groups, but not in maximum acute GU side effects and late maximum GI and GU effects.

CONCLUSIONS

High-risk prostate cancer patients treated with doses of 78 Gy had significantly better bNED rates. Compared to the historical 66 Gy group, 50% more patients achieved bNED after a follow-up of 9 years.

Ten-years outcome analysis in patients with clinically localized prostate cancer treated by radical prostatectomy or external beam radiation therapy

Purpose

Since there was no consensus on treatment options for localized prostate cancer, we performed a retrospective study to compare the long-term survival benefit of radiotherapy (RT) versus laparoscopic radical prostatectomy (LRP) in Taiwan.

Methods

218 patients with clinically localized prostate cancer treated between 2008 and 2017 (64 with LRP and 154 with RT) were enrolled in this study. The outcomes of RT and LRP were assessed after patients were stratified according to Gleason score, stage, and risk group. Crude survival, prostate cancer-specific survival, and metastasis-free survival were evaluated using the log-rank test.

Results

The 5-year crude survival rate was 93.3% in the LRP group and 59.3% in the RT group. A significant survival benefit was found in the LRP group compared with the RT group (p = 0.004). Furthermore, significant differences were found in disease-specific survival (93.3% vs. 64.7%, p = 0.022) and metastasis-free survival (48% vs. 40.2%, p = 0.045) between the LRP and RT groups.

Conclusions

Men with localized prostate cancer treated initially with LRP had a lower risk of prostate cancer-specific death and metastases compared with those treated with RT.

Dose-volume analysis of planned versus accumulated dose as a predictor for late gastrointestinal toxicity in men receiving radiotherapy for high-risk prostate cancer

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Interfractional variations in organs at risk were observed in prostate radiotherapy.

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Rectal accumulated dose was significantly higher at the intermediate-high dose region.

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Rectal planned dose was significantly higher at the very high dose region.

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Dose>78.2 Gy to 0.03 cc of rectum was predictive of late Grade 2 toxicity.

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Patient age>72 years was predictive of late Grade 2 rectal toxicity.

Background and purpose

Significant dose deviations have been reported between planned (D_P) and accumulated (D_A) dose in prostate radiotherapy. This study aimed to develop multivariate analysis (MVA) models associating Grade 1 and 2 gastrointestinal (GI) toxicity with clinical and D_P or D_A dosimetric variables separately.

Materials and methods

Dose volume (DV) metrics were compared between D_A and D_P for 150 high-risk prostate cancer patients. MV models were generated from significant clinical and dosimetric variables (p < 0.05) at univariate level. Dose-based-region of interest (DB-ROI) metrics were included. Model performance was measured, and additional subgroup analysis were performed.

Results

Rectal D_A demonstrated a higher intermediate-high dose (V_{30-65 Gy} and DB-ROI at 15–50 mm) compared to D_P. Conversely, at the very high dose region, rectal D_A (V_{75 Gy} and DB-ROI at 5–10 mm) were significantly lower. In MVA, rectal DB-ROI at 10 mm was predictive for Grade ≥ 1 GI toxicity for D_A and D_P. Age, rectal D_A for D_{0.03 cc}, and rectal D_P for DB-ROI 10 mm were predictors for Grade 2 GI toxicity. Subgroup analysis revealed that patients ≥ 72 years old and a rectal D_A of ≥ 78.2 Gy were highly predictive of Grade 2 GI toxicity.

Conclusions

The dosimetric impact of a higher dose rectal dose in D_A due to volumetric changes was minimal and was not predictive of detrimental clinical toxicity apart from rectal D_{0.03 cc} ≥ 78.2 Gy for Grade 2 GI toxicity. The use of the DB-ROI method can provide equivalent predictive power as the DV method in toxicity prediction.

Prostate cancer: Therapeutic prospect with herbal medicine

Prostate cancer (PCa) is a major cause of morbidity and mortality in men worldwide. A geographic variation on the burden of the disease suggested that the environment, genetic makeup, lifestyle, and food habits modulate one's susceptibility to the disease. Although it has been generally thought to be an older age disease, and awareness and timely execution of screening programs have managed to contain the disease in the older population over the last decades, the incidence is still increasing in the population younger than 50. Existing treatment is efficient for PCa that is localized and responsive to androgen. However, the androgen resistant and metastatic PCa are challenging to treat. Conventional radiation and chemotherapies are associated with severe side effects in addition to being exorbitantly expensive. Many isolated phytochemicals and extracts of plants used in traditional medicine are known for their safety and diverse healing properties, including many with varying levels of anti-PCa activities. Many of the phytochemicals discussed here, as shown by many laboratories, inhibit tumor cell growth and proliferation by interfering with the components in the pathways responsible for the enhanced proliferation, metabolism, angiogenesis, invasion, and metastasis in the prostate cells while upregulating the mechanisms of cell death and cell cycle arrest. Notably, many of these agents simultaneously target multiple cellular pathways. We analyzed the available literature and provided an update on this issue in this review article.

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Prostate cancer in a major cause of death in older population worldwide.

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Efficacies of current treatment options are limited in many cases.

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Phytochemicals and extracts isolated from plants show anti-prostate cancer activity with unique mechanisms.

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Certain phytochemicals alone or in combination with current chemotherapy show therapeutic promise.

The efficacy and tolerability of ultra-hypofractionated radiotherapy in low-intermediate risk prostate cancer patients: single center experience

BACKGROUND

We aimed to investigate the efficacy and tolerability of ultra-hypofractionated radiotherapy (UHRT) in the treatment of low and intermediate-risk prostate cancer patients.

METHODS

This retrospective study was conducted using data derived from 44 patients who underwent UHRT, and toxicity assessment and clinical response were investigated. Treatment consisted of 35-36.25 Gy in 5 fractions using stereotactic ablative radiotherapy (SABR) with the Linac-based delivery system.

RESULTS

The median duration of follow-up was 52 months (8-68 months) and the median age was 71.5 years (54-85 years). Twenty-seven patients were assigned as intermediate-risk, whereas 17 patients had low-risk. The 5-year overall survival rate was 87.8%, while the 5-year biochemical recurrence-free survival (bRFS) rate was 97.4%. Acute grade 3 genitourinary (GU) side effect was not observed in any patient, whereas acute gastrointestinal (GI) system grade 3 side effect was seen in 6.8% of the patients. Late grade 3 GU and GI side effects were seen in 4.6% and 6.8% of the patients, respectively. In patients with planning target volume (PTV) ≥85 ml, acute grade ≥2 GU side effects were more common (p=.034).

CONCLUSION

Our data demonstrated that UHRT administered with volumetric arc therapy (VMAT) can be recommended for selected patients with low-intermediate risk prostate cancer. Further prospective, multicentric, controlled trials on larger series are warranted to reach more accurate conclusions.

Treatment Strategies for High-Risk Localized and Locally Advanced and Oligometastatic Prostate Cancer

Simple Summary

The definitions of locally advanced and oligometastatic prostate cancer are ambiguous, and there are no standard treatments for these. Although multidisciplinary treatment combining systemic and local treatment may be effective, there are many unresolved issues such as the choice of local treatment, use of new endocrine agents and chemotherapy, and selection of optimal patients. The present article discusses the definitions, diagnoses, and treatment of very high-risk prostate cancer and oligometastatic prostate cancer.

Abstract

Despite the significant advances in the treatment of high-risk prostate cancer, patients with very high-risk features such as being locally advanced (clinical stage T3–4 or minimal nodal involvement), having a high Gleason pattern, or with oligometastasis may still have a poor prognosis despite aggressive treatment. Multidisciplinary treatment with both local and systemic therapies is thought to be effective, however, unfortunately, there is still no standard treatment. However, in recent years, local definitive therapy using a combination of radiotherapy and androgen deprivation is being supported by several randomized clinical trials. This study reviews the current literature with a focus on the definition of very high-risk prostate cancer, the role of modern imaging, and its treatment options.

Impact of daily plan adaptation on organ-at-risk normal tissue complication probability for adrenal lesions undergoing stereotactic ablative radiation therapy

INTRODUCTION

Stereotactic ablative radiotherapy (SABR) can achieve good local control for metastatic adrenal lesions. Magnetic resonance (MR)-guidance with daily on-table plan adaptation can augment the delivery of SABR with greater dose certainty. The goal of this study was to quantify the potential clinical benefit MR-guided daily-adaptive adrenal SABR using the normal tissue complication probability (NTCP) framework.

METHODS

Patients treated with adrenal MR-guided SABR at a single institution were retrospectively reviewed. Lyman-Kutcher-Burman NTCP models were used to calculate the NTCP of upper abdominal organs-at-risk (OARs) at simulation and both before and after daily on-table plan adaptation. Differences in OAR NTCPs were assessed using signed-rank tests. Potential predictors of the benefits of adaptation were assessed by linear regression.

RESULTS

Fifty-two adrenal MR-guided SABR courses were analyzed. The baseline simulation plan underestimated the absolute stomach NTCP by 10.0% on average (95% confidence interval: 4.7-15.2%, p < 0.001). Daily on-table adaptation lowered absolute NTCP by 8.7% (4.2-13.2%, p < 0.001). The most significant predictor of the benefits of adaptation was lesion laterality (p = 0.018), with left-sided lesions benefitting more (13.3% [6.3-20.4%], p < 0.001) than right-sided lesions (2.1% [-1.6-5.7%], p = 0.25). Sensitivity analyses did not change the statistical significance of the findings.

CONCLUSION

NTCP analysis revealed that patients with left adrenal tumors were more likely to benefit from MR-guided daily on-table adaptive SABR using current dose/fractionation regimens due to reductions in predicted gastric toxicity. Right-sided adrenal lesions may be considered for dose escalation due to low predicted NTCP.

Quality assurance-based optimization (QAO): Towards improving patient-specific quality assurance in volumetric modulated arc therapy plans using machine learning

INTRODUCTION

Previous literature has shown general trade-offs between plan complexity and resulting quality assurance (QA) outcomes. However, existing solutions for controlling this trade-off do not guarantee corresponding improvements in deliverability. Therefore, this work explored the feasibility of an optimization framework for directly maximizing predicted QA outcomes of plans without compromising the dosimetric quality of plans designed with an established knowledge-based planning (KBP) technique.

MATERIALS AND METHODS

A support vector machine (SVM) was developed - using a database of 500 previous VMAT plans - to predict gamma passing rates (GPRs; 3%/3mm percent dose-difference/distance-to-agreement with local normalization) based on selected complexity features. A heuristic, QA-based optimization (QAO) framework was devised by utilizing the SVM model to iteratively modify mechanical treatment features most commonly associated with suboptimal GPRs. Specifically, leaf gaps (LGs) <50 mm were widened by random amounts, which impacts all aperture-based complexity features. 13 prostate KBP-guided VMAT plans were optimized via QAO using user-specified maximum LG displacements before corresponding changes in predicted GPRs and dose were assessed.

RESULTS

Predicted GPRs increased by an average of 1.14 ± 1.25% (p = 0.006) with QAO using a 3 mm maximum random LG displacement. There were small differences in dose, resulting in similarly small changes in tumor control probability (maximum increase = 0.05%) and normal tissue complication probabilities in the bladder, rectum, and femoral heads (maximum decrease = 0.2% in the rectum).

CONCLUSION

This study explored the feasibility of QAO and warrants future investigations of further incorporating QA endpoints into plan optimization.

Moderate hypofractionated post-prostatectomy radiation therapy is feasible and well tolerated: experience from a single tertiary cancer centre

PURPOSE

Conventional post-prostatectomy radiation therapy comprises 6.5-8 weeks of treatment, therefore, hypofractionated and shortened schemes arouse increasing interest. We describe our experience regarding feasibility and clinical outcome of a post-prostatectomy moderate hypofractionated image-guided radiotherapy schedule MATERIALS AND METHODS: From Oct 2015-Mar 2020, 113 patients, median age of 62 years-old (range 45-76) and prostate adenocarcinoma of low risk (30%), intermediate risk (49%) and high risk (21%) were included for adjuvant (34%) or salvage radiation therapy (66%) after radical prostatectomy (RP). All patients underwent radiotherapy with image-guided IMRT/VMAT to a total dose of 62.5 Gy in 2.5 Gy/fraction in 25 fractions. Sixteen patients (14%) received concomitant androgen deprivation therapy.

RESULTS

With a median follow-up of 29 months (range 3-60 months) all patients but three are alive. Eleven patients (10%) developed exclusive biochemical relapse while 19 patients (17%) presented macroscopically visible relapse: prostatectomy bed in two patients (2%), pelvic lymph nodes in 13 patients (11.5%) and distant metastases in four patients (4%). The 3 years actuarial rates for OS, bFRS, and DMFS were 99.1, 91.1 and 91.2%, respectively. Acute and late tolerance was satisfactory. Maximal acute genitourinary (AGU) toxicity was G2 in 8% of patients; maximal acute gastrointestinal (AGI) toxicity was G2 in 3.5% of patients; maximal late genitourinary (LGU) toxicity was G3 in 1% of patients and maximal late gastrointestinal (LGI) toxicity was G2 in 2% of patients. There were no cases of severe acute or late toxicity. No relationship was found between acute or late GI/GU adverse effects and dosimetric parameters, age, presence of comorbidities or concomitant treatments.

CONCLUSIONS

Hypofractionated radiotherapy (62.5 Gy in 25 2.5 Gy fractions) is feasible and well tolerated with low complication rates allowing for a moderate dose-escalation that offers encouraging clinical results for biochemical control and survival in patients with prostate cancer after radical prostatectomy.

Radiotherapy challenges in COVID era

The pandemic caused by the new coronavirus (SARS-CoV-2) associated with a disease named COVID-19 by the World Health Organization that began in late 2019 in Wuhan city has become a global public health problem. Only 2 months later, the new virus affected most countries of the world, the consequence being an overload of health systems, especially Intensive Care Units. Considered a category of patients at high risk of developing severe forms of the disease, cancer patients can develop a severe form of the disease, complicated by acute respiratory distress syndrome requiring mechanical ventilation. Radiotherapy, as a treatment included in the multidisciplinary management of cancer for both curative and palliative purposes, is also affected by the COVID-19 pandemic. COVID-19-positive or -suspected patients are a special category for which the decision to postpone treatment should be made based on the particularities of tumor biology and the radiobiological effect of a gap in radiation fractions delivery. Emergencies including spinal cord compressions, tumor bleeding, and brain metastases not responsive to corticosteroid treatment, should be considered a priority but the palliative treatment should be limited from one single fraction to maximum five fractions for spinal cord compression and whole brain radiotherapy. Radiotherapy for brain metastases does not bring a benefit in terms of overall survival for patients with life expectancy of days or weeks and dexamethasone treatment is the correct choice in this situation. In all settings, the approach of radiotherapy treatment must be adapted for both scenarios of an outbreak pandemic, when general measures of social distancing and protection by specific equipment of patients and radiotherapy staff are a priority, but also for a long period of coexistence with the virus with possible new “pandemic waves.”

Short fractionation radiotherapy for early prostate cancer in the time of COVID-19: long-term excellent outcomes from a multicenter Italian trial suggest a larger adoption in clinical practice

INTRODUCTION

To evaluate stereotactic body radiotherapy (SBRT) in low-risk Prostate Cancer patients as preferred treatment option in emergency health conditions.

MATERIALS AND METHODS

From April 2013 to September 2015, 28 patients with low-risk prostate cancer were prospectively enrolled. The SBRT prescribed dose was 36.25 Gy in 5 fractions, twice a week. Primary endpoints were acute and late toxicity. Secondary endpoints were biochemical recurrence free survival (bRFS) and overall survival.

RESULTS

Median follow-up was 65.5 months (range 52-81). No acute G3 or G4 toxicity was recorded. Acute G1 or G2 genitourinary (GU) toxicity occurred in 43% and acute G1-G2 gastrointestinal (GI) toxicity in 14%. Late G1 and G3 GU toxicity in 18% and 3.5%, respectively. The G3 toxicity was not directly attributable to radiotherapy. Late G1 GI toxicity occurred in 18%. 5yy bRFS was 96.5% (95% CI 82.3-99.4%).

CONCLUSIONS

Stereotactic body radiotherapy for early prostate cancer reported safe toxicity profile and a good clinical outcome at the median follow-up of 5 years. It may be an useful option if radiotherapy is required in emergency medical conditions.

Patterns of practice of androgen deprivation therapy combined to radiotherapy in favorable and unfavorable intermediate risk prostate cancer. Results of The PROACT Survey from the French GETUG Radiation Oncology group

PURPOSE

The intermediate-risk (IR) prostate cancer (PCa) group is heterogeneous in terms of prognosis. For unfavorable or favorable IR PCa treated by radiotherapy, the optimal strategy remains to be defined. In routine practice, the physician's decision to propose hormonal therapy (HT) is controversial. The PROACT survey aimed to evaluate pattern and preferences of daily practice in France in this IR population.

MATERIALS AND METHODS

A web questionnaire was distributed to French radiotherapy members of 91 centers of the Groupe d'Etude des Tumeurs Uro-Genitales (GETUG). The questionnaire included four sections concerning: (i) the specialists who prescribe treatments and multidisciplinary decisions (MTD) validation; (ii) the definition of IR subsets of patients; (iii) radiotherapy parameters; (iv) the pattern of practice regarding cardiovascular (CV) and (iv) metabolic evaluation. A descriptive presentation of the results was used.

RESULTS

Among the 82 responses (90% of the centers), HT schedules and irradiation techniques were validated by specific board meetings in 54% and 45% of the centers, respectively. Three-fourths (76%) of the centers identified a subset of IR patients for a dedicated strategy. The majority of centers consider PSA>15 (77%) and/or Gleason 7 (4+3) (87%) for an unfavorable IR definition. Overall, 41% of the centers performed systematically a CV evaluation before HT prescription while 61% consider only CV history/status in defining the type of HT. LHRH agonists are more frequently prescribed in both favorable (70%) and unfavorable (98%) IR patients. Finally, weight (80%), metabolic profile (70%) and CV status (77%) of patients are considered for follow-up under HT.

CONCLUSION

To the best of our knowledge, this is the first survey on HT practice in IR PCa. The PROACT survey indicates that three-quarters of the respondents identify subsets of IR-patients in tailoring therapy. The CV status of the patient is considered in guiding the HT decision, its duration and type of drug.

Comparative effectiveness of surgery and radiotherapy for survival of patients with clinically localized prostate cancer: A population-based coarsened exact matching retrospective cohort study

Radical prostatectomy and radiotherapy are currently the main treatment options for localized prostate cancer. However, no large cohort study comparing surgery and radiation has been performed in Japan or Asia. The objective of the current study was to compare the survival outcomes of patients with clinically localized prostate cancer and in elderly and young patients receiving surgery and radiotherapy. The survival outcomes of patients with localized prostate cancer (age at diagnosis ≤79 years, clinical T1-3) initially treated with surgery or radiotherapy were retrospectively analyzed. Data were collected from the population-based cancer registry of the Kanagawa Prefecture, Japan. A 1:1 coarsened exact matching of age at diagnosis, clinical T stage and cancer differentiation was performed between the two treatment groups. Patients were also categorized into two subgroups by age using a cutoff of 70 years for analysis. The cohort comprised 4,810 patients aged 50-79 years. No significant difference in cancer-specific survival (CSS) was observed between the two groups (P=0.612). However, the surgery group had significantly better overall survival (OS; P=0.004). When stratified for age, similar tendencies were observed in the elderly group (aged 70-79 years; CSS, P=0.961 and OS, P=0.007). No significant difference in either CSS or OS was identified in the younger group (P=0.550 and P=0.408, respectively). Intrinsic deaths were more likely to occur in elderly patients treated with radiotherapy than those undergoing surgery (69.3 vs. 78.2%; P=0.128). The results indicated that surgery provided significantly better OS than radiotherapy, particularly among the elderly. However, no significant difference was observed in CSS. These results should be interpreted with caution, given that some important factors were unavailable in the present study, such as prostate-specific antigen values and Gleason scores. Prospective trials evaluating these therapies are warranted.

A-blockers for the management of lower urinary tract symptoms in patients with prostate cancer treated with external beam radiotherapy: a randomized controlled study

BACKGROUND

This is a prospective study aiming to assess the efficacy of α-blockers in treating radiotherapy-induced symptoms of the lower urinary tract and its possible prophylactic role on acute urinary retention (AUR) in patients undergoing radical external beam radiotherapy (EBRT) for localized prostate cancer (PCa).

METHODS

Overall, 108 patients with localized PCa were recruited and randomly assigned in to two groups; 54 patients of Group 1 received tamsulosin 0.4 mg once daily with the initiation of EBRT and for 6 months and 54 patients of Group 2 served as the control group. All patients received radical EBRT and had post-void volume (Vres) assessment. The International Prostate Symptom Score (IPSS) questionnaire and evaluation of episodes of AUR were performed after the end of radiotherapy, at 3 and at 6 months.

RESULTS

The incidence of AUR was significantly (p = 0.027) lower in group 1 compared to group 2. No independent predictive factors for AUR were identified in regression analysis. The IPSS changes in univariate and multivariate analysis at 3 months showed significant correlation with α-blockers only, while at 6 months showed significant correlation with Vres assessments (at 3 and 6 months) and with α-blockers. Side effects due to medication were mild and none of the patients discontinued the treatment.

CONCLUSIONS

The selective use of α-blocker appears to prevent AUR in EBRT-treated patients. Although the administration of α-blockers might relieve patient-reported symptoms, there are no established independent predictive factors to distinguish patients who may benefit.

Target miss using PTV-based IMRT compared to robust optimization via coverage probability concept in prostate cancer

Purpose: Cure- and toxicity rates of prostate IGRT can both be affected by ill-chosen planning target volume (PTV) margins. For dose-escalated prostate radiotherapy, we studied the potential for organ at risk (OAR) sparing and compensation of prostate motion with robust plan optimization using the coverage probability (CovP) concept compared to conventional PTV-based IMRT.Material and methods: We evaluated plan quality of CovP-plans for 27 intermediate risk prostate cancer patients treated in a prospective study (78 Gy/39 fractions). Clinical target volume (CTV) and OARs were contoured on three separate CTs to capture movement and deformation. To define the internal target volume (ITV), the union of CTV1-3 was encompassed by an isotropic margin of 7 mm for the planning process. CovP-dose distribution is optimized considering weight factors for IMRT constraints derived from probabilities of systematic organ displacement in the three CTs. CovP-dose volume histograms (DVHs) were compared with additionally calculated conventional PTV-based IMRT plans. PTV-based IMRT was planned on one-single CT with an isotropically expanded CTV to generate the PTV (i.e., CTV1 + 7mm) and was evaluated on the two other CTs.Results: The CovP-concept showed higher robustness in target volume coverage. Target miss was frequently observed with PTV-based IMRT, resulting in cold spots until 70 Gy with the CovP-concept. The target dose at 74 Gy was comparable, while further the dose-escalation (75-78 Gy) was improved with PTV-based IMRT. However, dose-escalation with PTV-based IMRT was associated with increased OAR-doses, especially in high-dose areas.Conclusions: Probabilistic dose-escalated IMRT was feasible in this prospective study. Comparison of the CovP-concept with PTV-based IMRT revealed superiority with regard to target-coverage and sparing of OARs. The CovP-concept implements a robust plan optimization strategy for organ deformation and motions and could, therefore, serve as a less demanding compromise on the way to adaptive IGRT avoiding daily time-consuming re-planning. SUMMARYWe evaluated the robustness of coverage probability (CovP)-based IMRT plans within a prospective study for prostate cancer radiotherapy. The treatment plans were compared with newly calculated conventional PTV-based IMRT plans. We were able to show that CovP led to a clearly more robust target coverage by avoiding hot spots at OARs compared to conventional PTV-based IMRT. In addition, negative consequences of an inflated PTV can be ameliorated by a more relaxed CovP-based dose prescription.

Radiotherapy of prostate cancer: impact of treatment characteristics on the incidence of second tumors

BACKGROUND

It has been hypothesized that radiotherapy (RT) techniques delivering radiations to larger volumes (IMRT, VMAT) are potentially associated with a higher risk of second primary tumors. The aim of this study was to analyse the impact of RT technique (3D-CRT vs IMRT/VMAT) on the incidence of second tumors in prostate cancer (PCa) patients.

METHODS

A retrospective study on 2526 previously irradiated PCa patients was performed. Patients were treated with 3D-CRT (21.3%), IMRT (68.1%), or VMAT (10.6%). Second tumors incidence was analysed in 3 categories: pelvic, pelvic and abdominal, and "any site". The correlation with RT technique was analysed using log-rank test and Cox's proportional hazard method.

RESULTS

With a median follow-up of 72 months (range: 9-185), 92 (3.6%) cases of second tumors were recorded with 48 months (range: 9-152) median interval from RT. Actuarial 10-year second tumor free survival (STFS) was 87.3%. Ten-year STFS in patients treated with 3D-CRT and IMRT/VMAT was 85.8 and 84.5%, respectively (p: .627). A significantly higher 10-year cumulative incidence of second tumors in the pelvis was registered in patients treated with IMRT/VMAT compared to 3D-CRT (10.7% vs 6.0%; p: .033). The lower incidence of second pelvic cancers in patients treated with 3D-CRT was confirmed at multivariable analysis (HR: 2.42, 95%CI: 1.07-5.47, p: .034).

CONCLUSIONS

The incidence of second pelvic tumors after RT of PCa showed a significant correlation with treatment technique. Further analyses in larger series with prolonged follow-up are needed to confirm these results.

Rationale for hypofractionation

Fractionation was established more than fifty years ago as the best way to obtain a differential effect between tumors and normal tissues. However, new technologies allowed today to spare critical organs from the radiation fields. And so protracted courses of irradiation are no longer required. Hypofractionation have clear practical advantages over classical fractionation: it saves the patient time; it saves money for public health system; it reduces pressure on radiotherapy units. In several localization, it has proved to be as efficient as classical fractionation without increasing late effects. In prostate cancer, some radiobiological considerations argue in favor of a better efficiency, but clinical trials did not demonstrated differences in biological control. In conclusion, for all diseases where hypofractionation was demonstrated efficient, it must be fully implemented. Invoice procedures must be adapted to maintain a sufficient level of reimbursement of radiotherapy centers.

Technological evolution of radiation treatment: Implications for clinical applications

The contemporary approach to the management of a cancer patient requires an "ab initio" involvement of different medical domains in order to correctly design an individual patient's pathway toward cure. With new therapeutic tools in every medical field developing faster than ever before the patient care outcomes can be achieved if all surgical, drug, and radiation options are considered in the design of the appropriate therapeutic strategy for a given patient. Radiation therapy (RT) is a clinical discipline in which experts from different fields continuously interact in order to manage the multistep process of the radiation treatment. RT is found to be an appropriate intervention for diverse indications in about 50% of cancer patients during the course of their disease. Technologies are essential in dealing with the complexity of RT treatments and for driving the increasingly sophisticated RT approaches becoming available for the treatment of Cancer. High conformal techniques, namely intensity modulated or volumetric modulated arc techniques, ablative techniques (Stereotactic Radiotherapy and Stereotactic Radiosurgery), particle therapy (proton or carbon ion therapy) allow for success in treating irregularly shaped or critically located targets and for the sharpness of the dose fall-off outside the target. The advanced on-board imaging, including real-time position management systems, makes possible image-guided radiation treatment that results in substantial margin reduction and, in select cases, implementation of an adaptive approach. The therapeutic gains of modern RT are also due in part to the enhanced anticancer activity obtained by coadministering RT with chemotherapy, targeted molecules, and currently immune checkpoints inhibitors. These main clinically relevant steps forward in Radiation Oncology represent a change of gear in the field that may have a profound impact on the management of cancer patients.

Quality of Life Changes >10 Years After Postoperative Radiation Therapy After Radical Prostatectomy for Prostate Cancer

PURPOSE

To analyze long-term quality-of-life (QoL) changes related to postoperative radiation therapy (RT) after radical prostatectomy.

METHODS AND MATERIALS

Patients who received postoperative 3-dimensional conformal RT in the years 2003 to 2008 with 1.8 to 2.0 Gy fractions up to 66.0 to 66.6 Gy (n = 181) were surveyed using the Expanded Prostate Cancer Index Composite questionnaire before the beginning of RT (A); on the last day (B); and 2 months (C), 1 to 3 years (D), 6 to 9 years (E), and 10 to 13 years (F) after RT.

RESULTS

Mean urinary bother, urinary incontinence bother, and bowel bother score changes (in relation to baseline at time A) of 13, 14, and 7 and 14, 15, and 7 were found at times E and F, respectively (P < .01 for all comparisons). Sexual function scores decreased 6 and 8 points on average (P < .01). Patient age at the time of RT had a considerable impact on urinary bother and urinary incontinence bother, with increasing differences over time when comparing patients aged <68 versus ≥68 years: 0 versus 7 and 0 versus 7 points at time D and 8 versus 23 and 6 versus 35 points at time F, respectively. Patients who did not respond to RT with a decreasing prostate-specific antigen level had greater urinary and urinary incontinence bother and bowel bother score changes >10 years after treatment (25 vs 12; P = .04, 36 vs 10; P = .03, and 20 vs 5; P = .07, respectively). A higher rectal dose was associated with greater acute and long-term bowel bother score decrease. No correlation was found between the dose to the bladder and QoL changes.

CONCLUSIONS

In contrast to early evaluations in the first years, significantly decreasing QoL in the urinary, bowel, and sexual domains was found >5 years after RT. Aging is likely to be a major factor. Younger patients who responded to the treatment had the most favorable long-term QoL results. As 3-dimensional conformal RT was used in this study, intensity modulated concepts could result in improved outcomes.

Early and late side effects, dosimetric parameters and quality of life after proton beam therapy and IMRT for prostate cancer: a matched-pair analysis

Purpose: To compare early and late toxicities, dosimetric parameters and quality of life (QoL) between conventionally fractionated proton beam therapy (PBT) and intensity-modulated radiation therapy (IMRT) in prostate cancer (PCA) patients. Methods: Eighty-eight patients with localized PCA treated between 2013 and 2017 with either definitive PBT (31) or IMRT (57) were matched using propensity score matching on PCA risk group, transurethral resection of the prostate, prostate volume, diabetes mellitus and administration of anticoagulants resulting in 29 matched pairs. Early and late genitourinary (GU) and gastrointestinal (GI) toxicities according to Common Terminology Criteria for Adverse Events (CTCAE) and QoL based on EORTC-QLQ-C30/PR25 questionnaires were collected prospectively until 12 months after radiotherapy (RT). Associations between toxicities and dose-volume parameters in corresponding organs at risk (OARs) were modeled by logistic regression. Results: There were no significant differences in GI and GU toxicities between both treatment groups except for late urinary urgency, which was significantly lower after PBT (IMRT: 25.0%, PBT: 0%, p = .047). Late GU toxicities and obstruction grade ≥2 were significantly associated with the relative volume of the anterior bladder wall receiving 70 Gy and the entire bladder receiving 60 Gy, respectively. The majority of patients in both groups reported high functioning and low symptom scores for the QoL questionnaires before and after RT. No or little changes were observed for most items between baseline and 3 or 12 months after RT, respectively. Global health status increased more at 12 months after IMRT (p = .040) compared to PBT, while the change of constipation was significantly better at 3 months after PBT compared to IMRT (p = .034). Conclusions: Overall, IMRT and PBT were well tolerated. Despite the superiority of PBT in early constipation and IMRT in late global health status compared to baseline, overall QoL and the risks of early and late GU and GI toxicities were similar for conventionally fractionated IMRT and PBT.

The case for radiotherapy in a Value based environment

AIM

Describe the Value proposition for radiotherapy (RT) in the United States.

BACKGROUND

In the United States since 2005, two forces have worked to decrease RT cost per patient: Federal changes in reimbursement and hypofractionation of treatment courses. We theorize that these have driven stable reimbursement in the context of increasing technology of intensity modulation (IMRT) and image guidance (IGRT). This phenomenon provides increasing Value of the discipline to patients and systems.

MATERIALS AND METHODS

We searched the Medicare Physician/Supplier data for Program Payments per Person with Utilization for 2000 through 2016. This involves two databases: Enrollment Database (EDB) for 2000-2012 and Common Medicare Enrollment (CME) since 2013. RT payments to individual patients accessing services were retrieved.

RESULTS

Taking into account the change of calculation algorithm used by CMS in 2013, costs per patient were similar in 2012 and 2003, and 2016 and 2013.

CONCLUSIONS

In the United States, stabilizing costs in the face of increasing work, better outcomes, and decreased toxicity contributes to increasing RT value over the past 10 years.

Pelvic Complications After Prostate Cancer Radiation Therapy and Their Management: An International Collaborative Narrative Review

CONTEXT

Radiotherapy used for treating localized prostate cancer is effective at prolonging cancer-specific and overall survival. Still, acute and late pelvic toxicities are a concern, with gastrointestinal (GI) and genitourinary (GU) sequelae being most common as well as other pelvic complications.

OBJECTIVE

To present a critical review of the literature regarding the incidence and risk factors of pelvic toxicity following primary radiotherapy for prostate cancer and to provide a narrative review regarding its management.

EVIDENCE ACQUISITION

A collaborative narrative review of the literature from 2010 to present was conducted.

EVIDENCE SYNTHESIS

Regardless of the modality used, the incidence of acute high-grade pelvic toxicity is low following conventionally fractionated external beam radiotherapy (EBRT). After moderate hypofractionation, the crude cumulative incidences for late grade 3 or higher (G3+) GI and GU complications are as high as 6% and 7%, respectively. After extreme hypofractionation, the 5-yr incidences of G2+ GU and GI toxicities are 3-9% and 0-4%, respectively. Following brachytherapy monotherapy, crude rates of late G3+ GU toxicity range from 6% to 8%, while late GI toxicity is rare. With combination therapy (EBRT and brachytherapy), the cumulative incidence of late GU toxicity is high, between 18% and 31%; however, the prevalence is lower at 4-14%. Whole pelvic radiotherapy remains a controversial treatment option as there is increased G3+ GI toxicity compared with prostate-only treatment, with no overall survival benefit. Proton beam therapy appears to have similar toxicity to photon therapies currently in use. With respect to specific complications, urinary obstruction and urethral stricture are the most common severe urinary toxicities. Rectal and urinary bleeding can be recurrent long-term toxicities. The risk of hip fracture is also increased following prostate radiotherapy. The literature is mixed on the risk of in-field secondary pelvic malignancies following prostate radiotherapy. Urinary and GI fistulas are rare complications. Management of these toxicities may require invasive treatment and reconstructive surgery for refractory and severe symptoms.

CONCLUSIONS

There has been progress in the delivery of radiotherapy, enabling the administration of higher doses with minimal tradeoff in terms of slightly increased or equal toxicity. There is a need to focus future improvements in radiotherapy on sparing critical structures to reduce GU and GI morbidities. While complications such as fistulae, bone toxicity, and secondary malignancy are rare, there is a need for higher-quality studies assessing these outcomes and their management.

PATIENT SUMMARY

In this report, we review the literature regarding pelvic complications following modern primary prostate cancer radiotherapy and their management. Modern radiotherapy technologies have enabled the administration of higher doses with minimal increases in toxicity. Overall, high-grade long-term toxicity following prostate radiotherapy is uncommon. Management of late high-grade pelvic toxicities can be challenging, with patients often requiring invasive therapies for refractory cases.

Impact of image guidance on toxicity and tumour outcome in moderately hypofractionated external-beam radiotherapy for prostate cancer

To report toxicity and efficacy outcome of moderately hypofractionated image-guided external-beam radiotherapy in a large series of patients treated for prostate cancer (PCa). Between 10/2006 and 12/2015, 572 T1-T3N0M0 PCa patients received 70.2 Gy in 26 fractions at 2.7 Gy/fraction: 344 patients (60%) with three-dimensional conformal radiotherapy (3D-CRT) and 228 (40%) with intensity-modulated radiotherapy (IMRT). Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria and Houston definition (nadir + 2) were used for toxicity and biochemical failure evaluation, respectively. Median age was 74 years (interquartile range 69-77). Compared with 3D-CRT, in IMRT group more high-risk patients (29% vs 18%; P = 0.002) and more high-volume target (75% vs 60%; P < 0.001) were included. Acute gastro-intestinal (GI) toxicity G > 1 were registered in 8% and in 11% IMRT and 3D-CRT patients, respectively, whereas late GI G > 1 were observed in 2% and 16% IMRT and 3D-CRT patients, respectively. Acute genito-urinary (GU) toxicity G > 1 were registered in 26% and 40% IMRT and 3D-CRT patients, respectively, whereas late GU G > 1 occurred in 5% IMRT and 15% 3D-CRT patients. Multivariate proportional hazard Cox models confirmed significantly greater risk of late toxicity with 3D-CRT compared to IMRT for GU > 1 (P = 0.004) and for GI > 1 (P < 0.001). With a median 4-year follow-up, overall survival (OS), clinical progression-free survival (cPFS) and biochemical PFS (bPFS) for the whole series were 91%, 92% and 91%, respectively. cPFS and bPFS were significantly different by risk groups. Multivariate Cox models for bPFS and cPFS showed no difference between irradiation techniques and a significant impact of risk group and initial PSA. Moderately hypofractionated radiotherapy is a viable treatment option for localized PCa with excellent tumour control and satisfactory toxicity profile. IMRT seems associated with a reduction in toxicity, whereas tumour control was equal between IMRT and 3D-CRT patients and depended mainly on the risk category.

Quality of life worsened the most severely in patients immediately after intensity-modulated radiotherapy for prostate cancer

Purpose

The aim of this study was to evaluate the chronological changes in lower urinary tract symptoms (LUTSs), disease-related quality of life (QOL), and health-related QOL (HR-QOL) of patients who received intensity-modulated radiotherapy (IMRT).

Patients and methods

In 121 patients who had received IMRT and were followed up for >2 years, the International Prostate Symptom Score (IPSS), Overactive Bladder Symptom Score (OABSS), Expanded Prostate Cancer Index Composite (EPIC), and 8-Item Short-Form Health Survey (SF-8) were used before IMRT, at the halfway point in IMRT, immediately after IMRT, and 1–24 months after the completion of IMRT.

Results

The IPSS and OABSS and the urinary and bowel domains of the EPIC indicated that QOL worsened at the halfway point in IMRT, further worsened more severely immediately after IMRT, and then improved. The sexual domain of the EPIC significantly decreased at the halfway point in IMRT, which significantly lowered until 24 months. The scores of physical functioning, role physical, bodily pain, vitality, social functioning, and role emotional domains in the SF-8 significantly decreased and reached their lowest points immediately after IMRT.

Conclusion

QOL worsened the most severely in patients immediately after IMRT for prostate cancer. This knowledge can influence treatment recommendations and enable patients to make better informed decisions.

Analysis of Gastrointestinal Toxicity in Patients Receiving Proton Beam Therapy for Prostate Cancer: A Single-Institution Experience

Purpose

We characterized both physician- and patient-reported rates of gastrointestinal (GI) toxicity in patients treated with proton beam therapy (PBT) at our institution for prostate adenocarcinoma and identified factors associated with toxicity.

Methods and materials

We treated 192 patients with PBT between July 2013 and July 2016. Included patients had ≥1 year of follow-up. Potential preexisting clinical and treatment-related risk factors for GI toxicity were recorded. Common Terminology Criteria for Adverse Events version 4.0 was used to score toxicity. Expanded Prostate Cancer Index Composite (EPIC) bowel domain questionnaires assessed patient-reported quality of life. Associations between grade (GR) 2+ toxicity and clinical, treatment, and dosimetric factors were assessed using Cox models and corresponding hazard ratios.

Results

The median follow-up was 1.7 years. Most of the observed GI toxicity (>90%) was in the form of rectal bleeding (RB). GR2+ GI toxicity and RB actuarial rates specifically at 2 years were 21.3% and 20.4%, respectively. GR3 toxicity was rare, with only 1 observed RB event. No GR4/5 toxicity was seen. The EPIC bowel domain median score was 96 (range, 61-100) pretreatment, 93 (range, 41-100) at 1 year, 89 (range, 57-100) at 1.5 years, and 89 (range, 50-100) at 2 years. Anticoagulation use was the only factor selected during multivariate analysis for predicting GR2+ RB, with a resulting concordance index of 0.59 (95% confidence interval, 0.48-0.68; P = .088). Type of proton technology (pencil beam scanning vs uniform scanning) and number of fields treated per day (1 vs 2) showed no significant difference in toxicity rate.

Conclusions

PBT was associated with acceptable rates of GR2+ transient GI toxicity, mostly in the form of RB, which correlated with anticoagulation use. High EPIC bowel domain quality of life was maintained in the 2 years after treatment.

How Histopathologic Tumor Extent and Patterns of Recurrence Data Inform the Development of Radiation Therapy Treatment Volumes in Solid Malignancies

The ability to deliver highly conformal radiation therapy using intensity-modulated radiation therapy and particle therapy provides for new opportunities to improve patient outcomes by reducing treatment-related morbidities following radiation therapy. By reducing the volume of normal tissue exposed to radiation therapy (RT), while also allowing for the opportunity to escalate the dose of RT delivered to the tumor, use of conformal RT delivery should also provide the possibility of expanding the therapeutic index of radiotherapy. However, the ability to safely and confidently deliver conformal RT is largely dependent on our ability to clearly define the clinical target volume for radiation therapy, which requires an in-depth knowledge of histopathologic extent of different tumor types, as well as patterns of recurrence data. In this article, we provide a comprehensive review of the histopathologic and radiographic data that provide the basis for evidence-based guidelines for clinical tumor volume delineation.

Image-guided radiotherapy for prostate cancer

Intensity-modulated radiotherapy (IMRT) has become the standard radiotherapy technology utilized for the treatment of prostate cancer, as it permits the delivery of highly conformal radiation dose distributions. Image-guided radiotherapy (IGRT) is an essential companion to IMRT that allows the treatment team to account for daily changes in target anatomy and positioning. In the present review, we will discuss the different sources of geometric uncertainty and review the rationale behind using IGRT in the treatment of prostate cancer. We will then describe commonly employed IGRT techniques and review their benefits and drawbacks. Additionally, we will review the evidence suggesting a potential clinical benefit to utilizing IGRT.

Intensity-modulated radiotherapy for prostate cancer

Radiation therapy (RT) is a curative treatment modality for localized prostate cancer. Over the past two decades, advances in technology and imaging have considerably changed RT in prostate cancer treatment. Treatment has evolved from 2-dimensional (2D) planning using X-ray fields based on pelvic bony landmarks to 3-dimensional (3D) conformal RT (CRT) which uses computed tomography (CT) based planning. Despite improvements with 3D-CRT, dose distributions often remained suboptimal with portions of the rectum and bladder receiving unacceptably high doses. In more recent years, intensity-modulated radiation therapy (IMRT) has become the standard of care to deliver external beam RT. IMRT uses multiple radiation beams of different shapes and intensities delivered from a wide range of angles to ‘paint’ the radiation dose onto the tumor. IMRT allows for a higher dose of radiation to be delivered to the prostate while reducing dose to surrounding organs. Multiple clinical trials have demonstrated improved cancer outcomes with dose escalation, but toxicities using 3D-CRT and escalated doses have been problematic. IMRT is a method to deliver dose escalated RT with more conformal dose distributions than 3D-CRT and has been associated with improved toxicity profiles. IMRT also appears to be the safest method to deliver hypofractionated RT and pelvic lymph node radiation. The purpose of this review is to summarize the technical aspects of IMRT planning and delivery, and to review the literature supporting the use of IMRT for prostate cancer.

Treatment-related toxicity in men who received Intensity-modulated versus 3D-conformal radiotherapy after radical prostatectomy: A national population-based study

BACKGROUND AND PURPOSE

In the post-prostatectomy setting the value of Intensity-modulated (IMRT) relative to 3D-conformal radiotherapy (3D-CRT) in reducing toxicity remains unclear. We compared genitourinary (GU) and gastrointestinal (GI) toxicity after post-prostatectomy IMRT or 3D-CRT.

MATERIALS AND METHODS

A population-based study of all patients treated with post-prostatectomy 3D-CRT (n = 2422) and IMRT (n = 603) was conducted between January 1 2010 and December 31 2013 in the English National Health Service. We identified severe GI and GU toxicity using a validated coding-framework and compared IMRT and 3D-CRT using a competing-risks proportional hazards regression analysis.

RESULTS

There was no difference in GI toxicity between patients who received IMRT and 3D-CRT (3D-CRT: 5.8 events/100 person-years; IMRT: 5.5 events/100 person-years; adjusted HR: 0.85, 95%CI: 0.63-1.13; p = 0.26). The GU toxicity rate was lower with IMRT but this effect was not statistically significant (3D-CRT: 5.4 events/100 person-years; IMRT: 3.8 events/100 person-years; adjusted HR: 0.76, 95%CI: 0.55-1.03; p = 0.08).

CONCLUSIONS

The use of post-prostatectomy IMRT compared to 3D-CRT is not associated with a statistically significant reduction in rates of severe GU and GI toxicity, although there is some evidence that GU toxicity is lower with IMRT. We would caution against rapid transition to post-prostatectomy IMRT until further evidence is available supporting its superiority.

Interventions to reduce acute and late adverse gastrointestinal effects of pelvic radiotherapy for primary pelvic cancers

BACKGROUND

An increasing number of people survive cancer but a significant proportion have gastrointestinal side effects as a result of radiotherapy (RT), which impairs their quality of life (QoL).

OBJECTIVES

To determine which prophylactic interventions reduce the incidence, severity or both of adverse gastrointestinal effects among adults receiving radiotherapy to treat primary pelvic cancers.

SEARCH METHODS

We conducted searches of CENTRAL, MEDLINE, and Embase in September 2016 and updated them on 2 November 2017. We also searched clinical trial registries.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of interventions to prevent adverse gastrointestinal effects of pelvic radiotherapy among adults receiving radiotherapy to treat primary pelvic cancers, including radiotherapy techniques, other aspects of radiotherapy delivery, pharmacological interventions and non-pharmacological interventions. Studies needed a sample size of 20 or more participants and needed to evaluate gastrointestinal toxicity outcomes. We excluded studies that evaluated dosimetric parameters only. We also excluded trials of interventions to treat acute gastrointestinal symptoms, trials of altered fractionation and dose escalation schedules, and trials of pre- versus postoperative radiotherapy regimens, to restrict the vast scope of the review.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology. We used the random-effects statistical model for all meta-analyses, and the GRADE system to rate the certainty of the evidence.

MAIN RESULTS

We included 92 RCTs involving more than 10,000 men and women undergoing pelvic radiotherapy. Trials involved 44 different interventions, including radiotherapy techniques (11 trials, 4 interventions/comparisons), other aspects of radiotherapy delivery (14 trials, 10 interventions), pharmacological interventions (38 trials, 16 interventions), and non-pharmacological interventions (29 trials, 13 interventions). Most studies (79/92) had design limitations. Thirteen studies had a low risk of bias, 50 studies had an unclear risk of bias and 29 studies had a high risk of bias. Main findings include the following:Radiotherapy techniques: Intensity-modulated radiotherapy (IMRT) versus 3D conformal RT (3DCRT) may reduce acute (risk ratio (RR) 0.48, 95% confidence interval (CI) 0.26 to 0.88; participants = 444; studies = 4; I2 = 77%; low-certainty evidence) and late gastrointestinal (GI) toxicity grade 2+ (RR 0.37, 95% CI 0.21 to 0.65; participants = 332; studies = 2; I2 = 0%; low-certainty evidence). Conformal RT (3DCRT or IMRT) versus conventional RT reduces acute GI toxicity grade 2+ (RR 0.57, 95% CI 0.40 to 0.82; participants = 307; studies = 2; I2 = 0%; high-certainty evidence) and probably leads to less late GI toxicity grade 2+ (RR 0.49, 95% CI 0.22 to 1.09; participants = 517; studies = 3; I2 = 44%; moderate-certainty evidence). When brachytherapy (BT) is used instead of external beam radiotherapy (EBRT) in early endometrial cancer, evidence indicates that it reduces acute GI toxicity (grade 2+) (RR 0.02, 95% CI 0.00 to 0.18; participants = 423; studies = 1; high-certainty evidence).Other aspects of radiotherapy delivery: There is probably little or no difference in acute GI toxicity grade 2+ with reduced radiation dose volume (RR 1.21, 95% CI 0.81 to 1.81; participants = 211; studies = 1; moderate-certainty evidence) and maybe no difference in late GI toxicity grade 2+ (RR 1.02, 95% CI 0.15 to 6.97; participants = 107; studies = 1; low-certainty evidence). Evening delivery of RT may reduce acute GI toxicity (diarrhoea) grade 2+ during RT compared with morning delivery of RT (RR 0.51, 95% CI 0.34 to 0.76; participants = 294; studies = 2; I2 = 0%; low-certainty evidence). There may be no difference in acute (RR 2.22, 95% CI 0.62 to 7.93, participants = 110; studies = 1) and late GI toxicity grade 2+ (RR 0.44, 95% CI 0.12 to 1.65; participants = 81; studies = 1) between a bladder volume preparation of 1080 mls and that of 540 mls (low-certainty evidence). Low-certainty evidence on balloon and hydrogel spacers suggests that these interventions for prostate cancer RT may make little or no difference to GI outcomes.Pharmacological interventions: Evidence for any beneficial effects of aminosalicylates, sucralfate, amifostine, corticosteroid enemas, bile acid sequestrants, famotidine and selenium is of a low or very low certainty. However, evidence on certain aminosalicylates (mesalazine, olsalazine), misoprostol suppositories, oral magnesium oxide and octreotide injections suggests that these agents may worsen GI symptoms, such as diarrhoea or rectal bleeding.Non-pharmacological interventions: Low-certainty evidence suggests that protein supplements (RR 0.23, 95% CI 0.07 to 0.74; participants = 74; studies = 1), dietary counselling (RR 0.04, 95% CI 0.00 to 0.60; participants = 74; studies = 1) and probiotics (RR 0.43, 95% CI 0.22 to 0.82; participants = 923; studies = 5; I2 = 91%) may reduce acute RT-related diarrhoea (grade 2+). Dietary counselling may also reduce diarrhoeal symptoms in the long term (at five years, RR 0.05, 95% CI 0.00 to 0.78; participants = 61; studies = 1). Low-certainty evidence from one study (108 participants) suggests that a high-fibre diet may have a beneficial effect on GI symptoms (mean difference (MD) 6.10, 95% CI 1.71 to 10.49) and quality of life (MD 20.50, 95% CI 9.97 to 31.03) at one year. High-certainty evidence indicates that glutamine supplements do not prevent RT-induced diarrhoea. Evidence on various other non-pharmacological interventions, such as green tea tablets, is lacking.Quality of life was rarely and inconsistently reported across included studies, and the available data were seldom adequate for meta-analysis.

AUTHORS' CONCLUSIONS

Conformal radiotherapy techniques are an improvement on older radiotherapy techniques. IMRT may be better than 3DCRT in terms of GI toxicity, but the evidence to support this is uncertain. There is no high-quality evidence to support the use of any other prophylactic intervention evaluated. However, evidence on some potential interventions shows that they probably have no role to play in reducing RT-related GI toxicity. More RCTs are needed for interventions with limited evidence suggesting potential benefits.

Cost of New Technologies in Prostate Cancer Treatment: Systematic Review of Costs and Cost Effectiveness of Robotic-assisted Laparoscopic Prostatectomy, Intensity-modulated Radiotherapy, and Proton Beam Therapy

CONTEXT

Some of the high costs of robot-assisted radical prostatectomy (RARP), intensity-modulated radiotherapy (IMRT), and proton beam therapy may be offset by better outcomes or less resource use during the treatment episode.

OBJECTIVE

To systematically review the literature to identify the key economic trade-offs implicit in a particular treatment choice for prostate cancer.

EVIDENCE ACQUISITION

We systematically reviewed the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement and protocol. We searched Medline, Embase, and Web of Science for articles published between January 2001 and July 2016, which compared the treatment costs of RARP, IMRT, or proton beam therapy to the standard treatment. We identified 37, nine, and three studies, respectively.

EVIDENCE SYNTHESIS

RARP is costlier than radical retropubic prostatectomy for hospitals and payers. However, RARP has the potential for a moderate cost advantage for payers and society over a longer time horizon when optimal cancer and quality-of-life outcomes are achieved. IMRT is more expensive from a payer's perspective compared with three-dimensional conformal radiotherapy, but also more cost effective when defined by an incremental cost effectiveness ratio <$50 000 per quality-adjusted life year. Proton beam therapy is costlier than IMRT and its cost effectiveness remains unclear given the limited comparative data on outcomes. Using the Grades of Recommendation, Assessment, Development and Evaluation approach, the quality of evidence was low for RARP and IMRT, and very low for proton beam therapy.

CONCLUSIONS

Treatment with new versus traditional technologies is costlier. However, given the low quality of evidence and the inconsistencies across studies, the precise difference in costs remains unclear. Attempts to estimate whether this increased cost is worth the expense are hampered by the uncertainty surrounding improvements in outcomes, such as cancer control and side effects of treatment. If the new technologies can consistently achieve better outcomes, then they may be cost effective.

PATIENT SUMMARY

We review the cost and cost effectiveness of robot-assisted radical prostatectomy, intensity-modulated radiotherapy, and proton beam therapy in prostate cancer treatment. These technologies are costlier than their traditional counterparts. It remains unclear whether their use is associated with improved cure and reduced morbidity, and whether the increased cost is worth the expense.

National Population-Based Study Comparing Treatment-Related Toxicity in Men Who Received Intensity Modulated Versus 3-Dimensional Conformal Radical Radiation Therapy for Prostate Cancer

PURPOSE

To compare, in a national population-based study, severe genitourinary (GU) and gastrointestinal (GI) toxicity in patients with prostate cancer who were treated with radical intensity modulated radiation therapy (IMRT) or 3-dimensional conformal radiation therapy (3D-CRT).

METHODS AND MATERIALS

Patients treated with IMRT (n=6933) or 3D-CRT (n=16,289) between January 1, 2010 and December 31, 2013 in the English National Health Service were identified using cancer registry data, the National Radiotherapy Dataset, and Hospital Episodes Statistics, the administrative database of care episodes in National Health Service hospitals. We developed a coding system that identifies severe toxicity (at least grade 3 according to the National Cancer Institute Common Terminology Criteria for Adverse Events scoring system) according to the presence of a procedure and a corresponding diagnostic code in patients' Hospital Episodes Statistics records after radiation therapy. A competing risks regression analysis was used to estimate hazard ratios (HRs), comparing the incidence of severe GI and GU complications after IMRT and 3D-CRT, adjusting for patient, disease, and treatment characteristics.

RESULTS

The use of IMRT, as opposed to 3D-CRT, increased from 3.1% in 2010 to 64.7% in 2013. Patients who received IMRT were less likely than those receiving 3D-CRT to experience severe GI toxicity (4.9 vs 6.5 per 100 person-years; adjusted HR 0.66; 95% confidence interval 0.61-0.72) but had similar levels of GU toxicity (2.3 vs 2.4 per 100 person-years; adjusted HR 0.94; 95% confidence interval 0.84-1.06).

CONCLUSIONS

Prostate cancer patients who received radical radiation therapy using IMRT were less likely to experience severe GI toxicity, and they had similar GU toxicity compared with those who received 3D-CRT. These findings in an unselected "real-world" population support the use of IMRT, but further cost-effectiveness studies are urgently required.

Evaluation of the preimplantation worksheet in determining Calypso eligibility for men prescribed postprostatectomy radiotherapy with electromagnetic transponder guidance

This study aimed to assess the design and performance of the preimplant suitability worksheet in determining Calypso eligibility for prostate cancer patients prescribed postprostatectomy radiotherapy with electromagnetic transponder guidance. The medical records and radiotherapy planning datasets of 75 patients prospectively recruited between June 2015 and September 2016 to a Phase 2 trial evaluating electromagnetic transponder-guided postprostatectomy radiotherapy were retrospectively examined. Correlation and differences between computed tomography (CT)-defined greater trochanter and prostatic fossa landmarks were evaluated. Receiver operating characteristic curves were also generated to assess the expected and observed accuracy of the worksheet in determining Calypso eligibility. Strong correlation was demonstrated between anterior surface to planning CT-defined greater trochanter and prostate bed center distances (r = 0.95, p <0.001), with a mean difference between measurements of 1.1 cm (95% confidence interval [CI]: 0.9 to 1.3). A similar correlation coefficient was found for surface to greater trochanter location and posterior beacon location (r = 0.92, p <0.001) but with a reduced mean difference of 0.4 cm (95% CI: 0.1 to 0.6). Performance of the worksheet as assessed by planning CT data demonstrated excellent accuracy as a test to determine eligibility (area under the curve: 0.97; 95% CI: 0.92 to 1.00); however, this was not replicated using the same data captured clinically (area under the curve 0.83; 95% CI: 0.68 to 0.98). Although the greater trochanter is a good surrogate for the prostate bed center, it is better associated with the posterior beacon location. As a result, the worksheet will underestimate the truly eligible population if performed accurately and according to manufacturer guidelines. Theoretically, the worksheet could be improved if a cut off of 20 cm is used and the greater trochanter is accurately identified; however, the latter appears to be difficult to achieve in practice.

2D kV orthogonal imaging with fiducial markers is more precise for daily image guided alignments than soft-tissue cone beam computed tomography for prostate radiation therapy

Purpose

The hypothesis is that 2-dimensional kV orthogonal imaging with fiducial markers (kV-FM) and soft-tissue cone beam computed tomography (ST-CBCT) are equally reproducible for daily positional alignments for image guided (IG) intensity modulated radiation therapy (IMRT) for prostate cancer.

Methods and materials

Ten patients undergoing definitive treatment for prostate cancer with IG-IMRT were imaged daily with kV-FM and ST-CBCT. For each acquired kV and CBCT image, offline alignments to the digitally reconstructed radiograph or planning CT, respectively, were made twice by the same physician to assess intraobserver test-retest reproducibility. The 256 kV and 142 CBCT images were analyzed, and the test-retest analysis was performed again on a subset of images by another physician to verify the results.

Results

The results demonstrated that kV-FM had better intraobserver test-retest reproducibility in the anterior-posterior (AP; 95% confidence interval [CI] Pearson correlation coefficient [r], 0.987-0.991), left-right (LR; 95% CI r, 0.955-0.969), and superior-inferior (SI; 95% CI r, 0.971-0.980) directions for daily IG alignments compared with ST-CBCT (AP: 95% CI r, 0.804-0.877; LR: 95% CI r, 0.877-0.924; SI: 95% CI r, 0.791-0.869). Errors associated with intraobserver test-retest reproducibility were submillimeter with kV-FM (AP: 0.4 ± 0.7 mm; RL: 0.4 ± 1.0 mm; SI: 0.5 ± 0.7 mm) compared with ST-CBCT (AP: 2.1 ± 2.2 mm; LR: 1.3 ± 1.4 mm; SI: 1.2 ± 1.8 mm). The mean shift differences between kV-FM and ST-CBCT were 0.3 ± 3.8 mm for AP, −1.1 ± 8.5 mm for LR, and −2.0 ± 3.7 mm for SI. Dose-volume histograms were generated and showed that test-retest variability associated with ST-CBCT IG-alignments resulted in significantly increased dose to normal structures and a reduced planning target volume dose in many patients.

Conclusions

The kV-FM–based daily IG alignment for IMRT of prostate cancer is more precise than ST-CBCT, as assessed by a physician's ability to reproducibly align images. Given the magnitude of the error introduced by inconsistency in making ST-CBCT alignments, these data support a role for daily kV imaging of FM to enhance the precision of external beam dose delivery to the prostate.