Single-Fraction Stereotactic vs Conventional Multifraction Radiotherapy for Pain Relief in Patients With Predominantly Nonspine Bone Metastases: A Randomized Phase 2 Trial

Assessment of minimum target dose as a predictor of local failure after spine SBRT

OBJECTIVES

Metastasis-directed stereotactic body radiation therapy (SBRT) has demonstrated robust clinical benefits in carefully selected patients, improving local control and even overall survival (OS). We assess a large database to determine clinical and dosimetric predictors of local failure after spine SBRT.

METHODS

Spine SBRT treatments with imaging follow-up were identified. Patients were treated with a simultaneous integrated boost technique using 1 or 3 fractions, delivering 20-24 Gy in 1 fraction to the gross tumor volume (GTV) and 16 Gy to the low dose volume (or 27-36 Gy and 21-24 Gy for 3 fraction treatments). Exclusions included: lack of imaging follow-up, proton therapy, and benign primary histologies.

RESULTS

522 eligible spine SBRT treatments (68 % single fraction) were identified in 377 unique patients. Patients had a median OS of 43.7 months (95 % confidence interval: 34.3-54.4). The cumulative incidence of local failure was 10.5 % (7.4-13.4) at 1 year and 16.3 % (12.6-19.9) at 2 years. Local control was maximized at 15.3 Gy minimum dose for single-fraction treatment (HR = 0.31, 95 % CI: 0.17 - 0.56, p < 0.0001) and confirmed via multivariable analyses. Cumulative incidence of local failure was 6.1 % (2.6-9.4) vs. 14.2 % (8.3-19.8) at 1 year using this cut-off, with comparable findings for minimum 14 Gy. Additionally, epidural and soft tissue involvement were predictive of local failure (HR = 1.77 and 2.30).

CONCLUSIONS

Spine SBRT offers favorable local control; however, minimum dose to the GTV has a strong association with local control. Achieving GTV minimum dose of 14-15.3 Gy with single fraction SBRT is recommended whenever possible.

External Beam Radiation Therapy for Palliation of Symptomatic Bone Metastases: An ASTRO Clinical Practice Guideline

PURPOSE

This guideline provides evidence-based recommendations for palliative external beam radiation therapy (RT) in symptomatic bone metastases.

METHODS

The American Society for Radiation Oncology (ASTRO) convened a task force to address 5 key questions regarding palliative RT in symptomatic bone metastases. Based on a systemic review by the Agency for Health Research and Quality, recommendations using predefined consensus-building methodology were established; evidence quality and recommendation strength were also assessed.

RESULTS

For palliative RT for symptomatic bone metastases, RT is recommended for managing pain from bone metastases and spine metastases with or without spinal cord or cauda equina compression. Regarding other modalities with RT, for patients with spine metastases causing spinal cord or cauda equina compression, surgery and postoperative RT are conditionally recommended over RT alone. Furthermore, dexamethasone is recommended for spine metastases with spinal cord or cauda equina compression. Patients with non-spine bone metastases requiring surgery are recommended postoperative RT. Symptomatic bone metastases treated with conventional RT are recommended 800 cGy in 1 fraction (800 cGy/1fx), 2000 cGy/5fx, 2400 cGy/6fx, or 3000 cGy/10fx. Spinal cord or cauda equina compression in patients ineligible for surgery and receiving conventional RT are recommended 800 cGy/1fx, 1600 cGy/2fx, 2000 cGy/5fx, or 3000 cGy/10fx. Symptomatic bone metastases in selected patients with good performance status without surgery or neurological symptoms/signs are conditionally recommended SBRT over conventional palliative RT. Spine bone metastases re-irradiated with conventional RT are recommended 800 cGy/1fx, 2000 cGy/5fx, 2400 cGy/6fx, or 2000 cGy/8fx; non-spine bone metastases re-irradiated with conventional RT are recommended 800 cGy/1fx, 2000 cGy/5fx, or 2400 cGy/6fx. Determination of an optimal RT approach/regimen requires whole person assessment, including prognosis, previous RT dose if applicable, risks to normal tissues, quality of life, cost implications, and patient goals and values. Relatedly, for patient-centered optimization of treatment-related toxicities and quality of life, shared decision-making is recommended.

CONCLUSIONS

Based on published data, the ASTRO task force's recommendations inform best clinical practices on palliative RT for symptomatic bone metastases.

Role of Metastasis-Directed Therapy in Genitourinary Cancers

OPINION STATEMENT

The treatment of oligometastatic genitourinary cancers is a rapidly advancing field with ablative radiotherapy as one of the critical treatment components. The oligometastatic disease state, which can be defined as 1-5 metastatic sites with a controlled primary, represents a distinct clinical state where comprehensive ablative local therapies may provide improved outcomes. Enhanced imaging has increased the number of patients identified with oligometastatic disease. Evidence for improved outcomes with metastasis-directed therapy (MDT) in oligometastatic genitourinary cancers is increasing, and previously published outcome data continues to mature with an increasing body of prospective data to inform the role of MDT in histology-specific settings or in the context of systemic therapy. In select patients, MDT can offer benefits beyond improved local control and allow for time off of systemic therapy, prolonged time until next therapy, or even the hope of cure. However, treatment decisions for locally ablative therapy must be balanced with consideration towards safety. There are exciting advances in technologies to target and adapt treatment in real-time which have expanded options for safer delivery and dose escalation to metastatic targets near critical organs at risk. The role of systemic therapies in conjunction with MDT and incorporation of tumor genetic information to further refine prognostication and treatment decision-making in the oligometastatic setting is actively being investigated. These developments highlight the evolving field of treatment of oligometastatic disease. Future prospective studies combining MDT with enhanced imaging and integrating MDT with evolving systemic therapies will enable the optimal selection of patients most likely to benefit from this "all-or-none" approach and reveal settings in which a combination of therapies could result in synergistic outcomes.

Implementation Strategies to Promote Short-Course Radiation for Bone Metastases

Importance

For patients with nonspine bone metastases, short-course radiotherapy (RT) can reduce patient burden without sacrificing clinical benefit. However, there is great variation in uptake of short-course RT across practice settings.

Objective

To evaluate whether a set of 3 implementation strategies facilitates increased adoption of a consensus recommendation to treat nonspine bone metastases with short-course RT (ie, ≤5 fractions).

Design, Setting, and Participants

This prospective, stepped-wedge, cluster randomized quality improvement study was conducted at 3 community-based cancer centers within an existing academic-community partnership. Rollout was initiated in 3-month increments between October 2021 and May 2022. Participants included treating physicians and patients receiving RT for nonspine bone metastases. Data analysis was performed from October 2022 to May 2023.

Exposures

Three implementation strategies-(1) dissemination of published consensus guidelines, (2) personalized audit-and-feedback reports, and (3) an email-based electronic consultation platform (eConsult)-were rolled out to physicians.

Main Outcomes and Measures

The primary outcome was adherence to the consensus recommendation of short-course RT for nonspine bone metastases. Mixed-effects logistic regression at the bone metastasis level was used to model associations between the exposure of physicians to the set of strategies (preimplementation vs postimplementation) and short-course RT, while accounting for patient and physician characteristics and calendar time, with a random effect for physician. Physician surveys were administered before implementation and after implementation to assess feasibility, acceptability, and appropriateness of each strategy.

Results

Forty-five physicians treated 714 patients (median [IQR] age at treatment start, 67 [59-75] years; 343 women [48%]) with 838 unique nonspine bone metastases during the study period. Implementing the set of strategies was not associated with use of short-course RT (odds ratio, 0.78; 95% CI, 0.45-1.34; P = .40), with unadjusted adherence rates of 53% (444 lesions) preimplementation vs 56% (469 lesions) postimplementation; however, the adjusted odds of adherence increased with calendar time (odds ratio, 1.68; 95% CI, 1.20-2.36; P = .003). All 3 implementation strategies were perceived as being feasible, acceptable, and appropriate; only the perception of audit-and-feedback appropriateness changed before vs after implementation (19 of 29 physicians [66%] vs 27 of 30 physicians [90%]; P = .03, Fisher exact test), with 20 physicians (67%) preferring reports quarterly.

Conclusions and Relevance

In this quality improvement study, a multicomponent set of implementation strategies was not associated with increased use of short-course RT within an academic-community partnership. However, practice improved with time, perhaps owing to secular trends or physician awareness of the study. Audit-and-feedback was more appropriate than anticipated. Findings support the need to investigate optimal approaches for promoting evidence-based radiation practice across settings.

Long-Term Results of a Phase 1 Dose Escalation Trial of Ablative Stereotactic Body Radiation Therapy

PURPOSE

Stereotactic body radiation therapy is increasingly used for oligometastatic disease as well as palliation, but treatment protocols for nonspine bone and nodal metastases are lacking, with a wide variety of schedules applied.

METHODS AND MATERIALS

A prospective dose-escalation trial was initiated, involving 90 patients, among whom 52 (58%) had primary prostate tumors, 13 had breast tumors (14%), and 25 (28%) had other primary tumor types. All visible lymph node or nonspine bone oligometastases were treated in 3 consecutive cohorts: 5 × 7.0 Gy, 3 × 10.0 Gy, or 1 × 20.0 Gy.

RESULTS

Initial results revealed no dose-limiting toxicity after a median follow-up of 17.2 months. This update provides information on long-term toxicity, local failure (LF), and progression-free survival (PFS). After a median follow-up of 50 months, no new safety signals were observed. Grade 2 toxicity was 13%, 7% and 10% in the respective cohorts (P = .9), without grade 3 to 5 toxicities. LF rates were 9%, 3%, and 6% (P = .5) for the respective treatment groups, with an overall cumulative risk of LF of 7% (95% CI, 2-12) at 4 years. Median PFS was 16.5 months (95% CI, 9.8-21.5), and 4-year PFS was 21% (95% CI, 14-32). Median overall survival across groups was not reached (95% CI, 52.8 - not reached), 4-year OS was 68% (95% CI, 59-78). A subset of patients (23%) remained long-term disease-free, 37% had oligoprogressive disease at first recurrence and 40% developed polymetastatic relapse.

CONCLUSIONS

The safe and effective use of dose-escalated single-fraction stereotactic body radiation therapy for bone and lymph node metastases is supported by this trial, especially considering patient-convenience and cost-effectiveness. Caution is needed when generalizing these outcomes beyond breast and prostate cancer, given their underrepresentation in our study.

An Update on the Management of Bone Metastases

PURPOSE OF REVIEW

Increasing life expectancy among patients with advanced cancer has placed a greater emphasis on optimizing pain control and quality of life. Concurrently, significant advancements in radiotherapy for bone metastases have permitted for dose escalation strategies such as stereotactic radiotherapy. This review aims to provide updated information on the management of bone metastases in light of these developments.

RECENT FINDINGS

We reviewed recent studies regarding the role and details of external beam radiotherapy for bone metastases, with emphasis on differences by treatment site as well as intention (palliative versus ablative for oligometastases). Conventional palliative radiotherapy remains a mainstay of management. While stereotactic radiotherapy may augment durability of pain relief and even survival time, there are significant questions remaining regarding optimal dosing and patient selection. Radiotherapy for bone metastases continues to evolve, particularly with increasing use of stereotactic radiotherapy. Future studies are needed to clarify optimal dose, fractionation, modality, and patient selection criteria among different radiotherapy approaches.

A Prospective Study Assessing the Efficacy and Toxicity of Stereotactic Body Radiation Therapy for Oligometastatic Bone Metastases

Purpose

Stereotactic body radiation therapy (SBRT) is a promising treatment for oligometastatic disease in bone because of its delivery of high dose to target tissue and minimal dose to surrounding tissue. The purpose of this study is to assess the efficacy and toxicity of this treatment in patients with previously unirradiated oligometastatic bony disease.

Methods and Materials

In this prospective phase II trial, patients with oligometastatic bone disease, defined as ≤3 active sites of disease, were treated with SBRT at Brigham and Women's Hospital/Dana Farber Cancer Center and Beth Israel Deaconess Medical Center between December 2016 and May 2019. SBRT dose and fractionation regimen were not protocol mandated. Local progression-free survival, progression-free survival, prostatic specific antigen progression, and overall survival were reported. Treatment-related toxicity was also reported.

Results

A total of 98 patients and 126 lesions arising from various tumor histologies were included in this study. The median age of patients enrolled was 72.8 years (80.6% male, 19.4% female). Median follow-up was 26.7 months. The most common histology was prostate cancer (68.4%, 67/98). The most common dose prescriptions were 27/30 Gy in 3 fractions (27.0%, 34/126), 30 Gy in 5 fractions (16.7%, 21/126), or 30/35 Gy in 5 fractions (16.7%, 21/126). Multiple doses per treatment regimen reflect dose painting employing the lower dose to the clinical target volume and higher dose to the gross tumor volume. Four patients (4.1%, 4/98) experienced local progression at 1 site for each patient (3.2%, 4/126). Among the entire cohort, 2-year local progression-free survival (including death without local progression) was 84.8%, 2-year progression-free survival (including deaths as well as local, distant, and prostatic specific antigen progression) was 47.5%, and 2-year overall survival was 87.3%. Twenty-six patients (26.5%, 26/98) developed treatment-related toxicities.

Conclusions

Our study supports existing literature in showing that SBRT is effective and tolerable in patients with oligometastatic bone disease. Larger phase III trials are necessary and reasonable to determine long-term efficacy and toxicities.

Clinical Outcomes Among Patients Treated With Stereotactic Body Radiation Therapy to Femur Metastases for Oligometastatic Disease Control or Reirradiation: Results From a Large Single-Institution Experience

Purpose

There are limited data regarding outcomes after stereotactic body radiation therapy (SBRT) for femur metastases, which was an exclusion criteria for the Stereotactic Ablative Radiotherapy for the Comprehensive Treatment of Oligometastatic Cancers (SABR-COMET) trial. We aimed to characterize clinical outcomes from a large single institution experience.

Methods and Materials

Forty-eight patients with 53 lesions were consecutively treated with femur SBRT from May 2017 to June 2022. The Kaplan-Meier method and Cox proportional hazard models were used to characterize time-to-event endpoints and associations between baseline factors and clinical outcomes, respectively. Local control and locoregional control were defined as the absence of tumor progression within the radiation treatment field or within the treated femur, respectively.

Results

Most patients had Eastern Cooperative Oncology Group performance status 0 to 1 (90%), prostate (52%) or breast/lung (17%) cancer, and 1 to 3 lesions (100%), including 29 proximal and 5 distal. Fifty-seven percent of the lesions were treated with concurrent systemic therapy. Median planning target volume was 49.1 cc (range, 6.6-387 cc). Planning target volume V100 (%) was 99% (range, 90-100). Fractionation included 18 to 20 Gy/1F, 27 to 30 Gy/3F, and 28.5-40 Gy/5F. Forty-two percent had Mirels score ≥7 and most (94%) did not have extraosseous extension. Acute toxicities included grade 1 fatigue (15%), pain flare (7.5%), nausea (3.8%), and decreased blood counts (1.9%). Late toxicities included fracture (1.9%) at 1.5 years and osteonecrosis (4%) from dose of 40 Gy in 5F and 30 Gy in 5F (after prior 30 Gy/10F). One patient (2%) required fixation postradiation for progressive pain. With median follow-up 19.4 months, 1- and 2-year rates of local control were 94% and 89%, locoregional control was 83% and 67%, progression-free survival were 56% and 25%, and overall survival were 91% and 73%. Fifty percent of local regional recurrence events occurred within 5 cm of gross tumor volume.

Conclusions

Femur SBRT for oligometastatic disease control in well-selected patients was associated with good outcomes with minimal rates of acute and late toxicity. Patterns of local regional recurrence warrant consideration of larger elective volume coverage. Additional prospective study is needed.

Classification of Patients With Painful Tumors to Predict Response to Palliative Radiation Therapy

PURPOSE

This study aimed to identify factors affecting pain response to develop a patient classification system for palliative radiation therapy (RT).

METHODS AND MATERIALS

Our prospective observational study (UMIN000044984) provided data on patients who received palliative RT for painful tumors. The eligibility criteria were having a numerical rating scale (NRS) score of 2 or more before treatment and receiving palliative RT between August 2021 and September 2022. Post-RT follow-up was scheduled prospectively at 2, 4, 12, 24, 36, and 52 weeks. Pain response was assessed using the International Consensus Pain Response Endpoints criteria, with the primary outcome being the response rate within 12 weeks. Multivariable logistic regression was performed to identify factors affecting pain response and develop the classification system. Each class evaluated the differences in response rate, time to response, and progression.

RESULTS

Of the 488 registered lesions, 366 from 261 patients met the criteria. Most patients had bone metastases (75%), of whom 72% were using opioids and 22% underwent reirradiation. Conventional RT (eg, 8-Gy single fraction, 20 Gy in 5 fractions) was administered to 93% of patients. Over a median of 6.8 months of follow-up, the average NRS decreased from 6.1 to 3.4 at 12 weeks for 273 evaluable lesions, with a 60% response rate. Opioid use and reirradiation negatively affected the response rate in multivariate analysis (P < .01). Lesions were categorized into class 1 (no opioid use and no reirradiation; 89 lesions), class 2 (neither class 1 nor 3; 211 lesions), and class 3 (opioid use and reirradiation; 66 lesions), with respective response rates of 75%, 61%, and 36% (P < .001). Time to response was similar across the classes (P = .91), but the progression rates at 24 weeks differed (11%, 27%, and 63%, respectively; P < .001).

CONCLUSIONS

Opioid use and reirradiation are factors leading to significant variations in pain response rates and time to progression.

Practice and principles of stereotactic body radiation therapy for spine and non-spine bone metastases

Radiotherapy is the dominant treatment modality for painful spine and non-spine bone metastases (NSBM). Historically, this was achieved with conventional low dose external beam radiotherapy, however, stereotactic body radiotherapy (SBRT) is increasingly applied for these indications. Meta-analyses and randomized clinical trials have demonstrated improved pain response and more durable tumor control with SBRT for spine metastases. However, in the setting of NSBM, there is limited evidence supporting global adoption and large scale randomized clinical trials are in need. SBRT is technically demanding requiring careful consideration of organ at risk tolerance, and strict adherence to technical requirements including immobilization, simulation, contouring and image-guidance procedures. Additional considerations include follow up practices after SBRT, with appropriate imaging playing a critical role in response assessment. Finally, there is renewed research into promising new technologies that may further refine the use of SBRT in both spinal and NSBM in the years to come.

Prospective Evaluation of the Clinical Benefits of a Novel Tattoo-less Workflow for Nonspine Bone Stereotactic Body Radiation Therapy: Integrating Surface-Guidance With Triggered Imaging Reduces Treatment Time and Eliminates the Need for Tattoos

PURPOSE

Oligometastatic disease has expanded the indications for nonspine bone stereotactic body radiation therapy (NSB SBRT). We investigated whether optical surface monitoring systems (OSMS) could enable tattoo-less setup and substitute for 2-dimensional/3-dimensional or cone beam computed tomography (CBCT)-based mid-imaging in NSB SBRT.

METHODS AND MATERIALS

OSMS was incorporated in parallel with an existing workflow using pretreatment CBCT and 2-dimensional/3-dimensional kV/kV mid-imaging beginning November 2019. The ability of OSMS to detect out-of-tolerance (>2 mm/>2°) and commanded couch shifts was analyzed. A workflow incorporating OSMS reference captures, CBCT for pretreatment verification, and OSMS/triggered imaging (TI) for intrafraction monitoring was developed for rib/sternum SBRT beginning November 2021 and all NSB SBRT beginning February 2022. Treatment time and CBCT-related radiation dose between the OSMS and the non-OSMS intrafraction monitoring group was analyzed pre- and post-OSMS/TI workflow adoption. All fractions were analyzed through statistical process control with use of an XmR chart of treatment time per quarter from February 2019 to February 2023. Special cause rules were based on Institute for Healthcare Improvement criteria.

RESULTS

From February 2019 to February 2023, 1993 NSB SBRT fractions were delivered, including 234 rib, 109 sternum, 214 ilium, and 682 multisite. Over 20 commanded shifts, OSMS could detect 2-mm shifts to within 0.4 mm 67% of the time and 0.8 mm 95% of the time. All NSB SBRT sites showed significant reductions in treatment time, including the greatest improvement in rib total treatment (21.6-13.4 minutes; P = 1.16 × 10-17) and beam time (7.9-3.2 minutes; P = 7.32 × 10-27). Significant reductions in CBCT-related radiation were also observed for several NSB sites. These process improvements were associated with OSMS adoption.

CONCLUSIONS

Adoption of a novel NSB SBRT workflow incorporating OSMS/TI for bone intrafraction motion monitoring reduced treatment time and CBCT-related radiation exposure while also allowing for more continuous intrafraction motion monitoring for NSB SBRT. OSMS/TI enabled the transition to a tattoo-less workflow.

Lymphocyte-to-C Reactive Protein Ratio is an Independent Predictor of Survival Benefits for Hepatocellular Carcinoma Patients Receiving Radiotherapy

Background

Stereotactic body radiotherapy (SBRT) has emerged as an alternative approach for patients with hepatocellular carcinoma (HCC), and we aim to find potential prognostic biomarkers for HCC patients who received SBRT.

Methods

In this study, we retrospectively analyzed HCC patients who underwent SBRT in our institution from January 2018 to December 2022. The inflammatory parameters, along with baseline patients' characteristics were collected to elucidate the potential relationship with survival benefits and liver toxicities.

Results

Overall, 35 patients were enrolled in our study. For the efficacy population (25 patients who underwent SBRT for primary liver lesions), the objective response rate (ORR) and disease control rate (DCR) were 60% and 100%, respectively. The median progression-free survival (PFS) was 9.9 months [95% confidence interval (CI) 5.6-14.1 months], and the median overall survival (OS) was 18.5 months (95% CI 14.2-22.8 months). We further confirmed that higher baseline lymphocyte-C-reactive protein ratio (LCR) (≥2361.11) was positively related to both longer PFS (12.0 vs 4.3 months, P = 0.002) and OS (21.9 vs 11.4 months, P = 0.022). Moreover, patients with diabetes and higher alpha-fetoprotein (AFP) (≥400 ng/mL) were also found to be associated with worse OS. The most common hepatotoxicity was elevated gamma-glutamyl transferase (GGT) (84.0%).

Conclusion

In conclusion, for patients with inoperable HCC, SBRT resulted in satisfactory local control, survival benefits, and acceptable liver toxicity. Pre-radiotherapy LCR might be an independent and readily available predictor for survival, which facilitates us to find the most appropriate treatment options.

Quality of Decision Making in Radiation Oncology

High-quality decision making in radiation oncology requires the careful consideration of multiple factors. In addition to the evidence-based indications for curative or palliative radiotherapy, this article explores how, in routine clinical practice, we also need to account for many other factors when making high-quality decisions. Foremost are patient-related factors, including preference, and the complex interplay between age, frailty and comorbidities, especially with an ageing cancer population. Whilst clinical practice guidelines inform our decisions, we need to account for their applicability in different patient groups and different resource settings. With particular reference to curative-intent radiotherapy, we explore decisions regarding dose fractionation schedules, use of newer radiotherapy technologies and multimodality treatment considerations that contribute to personalised patient-centred care.

Stereotactic Body and Conventional Radiotherapy for Painful Bone Metastases: A Systematic Review and Meta-Analysis

Importance

Conventional external beam radiotherapy (cEBRT) and stereotactic body radiotherapy (SBRT) are commonly used treatment options for relieving metastatic bone pain. The effectiveness of SBRT compared with cEBRT in pain relief has been a subject of debate, and conflicting results have been reported.

Objective

To compare the effectiveness associated with SBRT vs cEBRT for relieving metastatic bone pain.

Data Sources

A structured search was performed in the PubMed, Embase, and Cochrane databases on June 5, 2023. Additionally, results were added from a new randomized clinical trial (RCT) and additional unpublished data from an already published RCT.

Study Selection

Comparative studies reporting pain response after SBRT vs cEBRT in patients with painful bone metastases.

Data Extraction and Synthesis

Two independent reviewers extracted data from eligible studies. Data were extracted for the intention-to-treat (ITT) and per-protocol (PP) populations. The study is reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

Main Outcomes and Measures

Overall and complete pain response at 1, 3, and 6 months after radiotherapy, according to the study's definition. Relative risk ratios (RRs) with 95% CIs were calculated for each study. A random-effects model using a restricted maximum likelihood estimator was applied for meta-analysis.

Results

There were 18 studies with 1685 patients included in the systematic review and 8 RCTs with 1090 patients were included in the meta-analysis. In 7 RCTs, overall pain response was defined according to the International Consensus on Palliative Radiotherapy Endpoints in clinical trials (ICPRE). The complete pain response was reported in 6 RCTs, all defined according to the ICPRE. The ITT meta-analyses showed that the overall pain response rates did not differ between cEBRT and SBRT at 1 (RR, 1.14; 95% CI, 0.99-1.30), 3 (RR, 1.19; 95% CI, 0.96-1.47), or 6 (RR, 1.22; 95% CI, 0.96-1.54) months. However, SBRT was associated with a higher complete pain response at 1 (RR, 1.43; 95% CI, 1.02-2.01), 3 (RR, 1.80; 95% CI, 1.16-2.78), and 6 (RR, 2.47; 95% CI, 1.24-4.91) months after radiotherapy. The PP meta-analyses showed comparable results.

Conclusions and Relevance

In this systematic review and meta-analysis, patients with painful bone metastases experienced similar overall pain response after SBRT compared with cEBRT. More patients had complete pain alleviation after SBRT, suggesting that selected subgroups will benefit from SBRT.

Clinical Outcomes After Stereotactic Body Radiation Therapy for Nonspinal Bone Metastases: A Systematic Review and Meta-analysis

There are limited data available on clinical outcomes after stereotactic body radiation therapy (SBRT) for nonspinal bone metastases. We performed a systematic review and meta-analysis to characterize local control (LC), overall survival (OS), pain response rates, and toxicity after SBRT. The primary outcomes were 1-year LC, incidence of acute and late grade 3 to 5 toxicities, and overall pain response rate at 3 months. The secondary outcome was 1-year OS. The Newcastle-Ottawa scale was used for assessment of study bias, with a median score of 5 for included studies (range, 4-8). Weighted random-effects meta-analyses were conducted to estimate effect sizes. We identified 528 patients with 597 nonspinal bone lesions in 9 studies (1 prospective study and 8 retrospective observational studies) treated with SBRT. The estimated 1-year LC rate was 94.6% (95% CI, 87.0%-99.0%). The estimated 3-month combined partial and complete pain response rate after SBRT was 87.7% (95% CI, 55.1%-100.0%). The estimated combined acute and late grade 3 to 5 toxicity rate was 0.5% (95% CI, 0%-5.0%), with an estimated pathologic fracture rate of 3.1% (95% CI, 0.2%-9.1%). The estimated 1-year OS rate was 71.0% (95% CI, 51.7%-87.0%). SBRT results in excellent LC and palliation of symptoms with minimal related toxicity. Prospective investigations are warranted to further characterize long-term outcomes of SBRT for patients with nonspinal bone metastases.

Recommendation on the technical and dosimetric data to be included in stereotactic body radiation therapy clinical trial publications based on a systematic review

The results of phase II and III trials on Stereotactic Body Radiation Therapy (SBRT) increased adoption of SBRT worldwide. The ability to replicate clinical trial outcomes in routine practice depends on the capability to reproduce technical and dosimetric procedures used in the clinical trial. In this systematic review, we evaluated if peer-reviewed publications of clinical trials in SBRT reported sufficient technical data to ensure safe and robust implementation in real world clinics. Twenty papers were selected for inclusion, and data was extracted by a working group of medical physicists created following the ESTRO 2021 physics workshop. A large variability in technical and dosimetric data were observed, with frequent lack of required information for reproducing trial procedures. None of the evaluated studies were judged completely reproducible from a technical perspective. A list of recommendations has been provided by the group, based on the analysis and consensus process, to ensure an adequate reproducibility of technical parameters in primary SBRT clinical trials. Future publications should consider these recommendations to assist transferability of the clinical trial in real world practice.

Short-term pain control after palliative radiotherapy for uncomplicated bone metastases: a prospective cohort study

This study aimed at evaluating the efficacy of different radiotherapy (RT) fractionation regimens in managing uncomplicated painful bone metastases (BM) and identifying predictive factors for pain control. Patients with 1 to 4 symptomatic BM from any primary solid tumors and a life expectancy exceeding 3 months were included in the study and received palliative RT, with SBRT restricted in the context of oligometastatic disease or in patients with good prognosis. Pain analysis using the Brief Pain Inventory (BPI) tool was conducted at baseline, 1 and 3 months after RT. Analgesic intake was recorded as morphine-equivalent doses (OME). Pain response was assessed using the International Consensus on Palliative Radiotherapy Endpoint (ICPRE). Multivariate logistic regression analyzed patient-related, tumor-related, and treatment-related factors predicting BM pain control at 3 months post-RT. From Feb 2022 to Feb 2023, 44 patients with 65 symptomatic BM were investigated. Breast (32%) and lung (24%) tumors were the most common primary tumors. Treatment plans included 3DCRT (60%) and VMAT (40%), with a median biological effective dose for tumors (BED) of 29 Gy [14-108]. All patients completed the 3-month follow-up. Pain response rates were 62% at 1 month and 60% at 3 months. Responders had better PS ECOG scores (67%; P = 0.008) and received active systemic therapies (67%: P = 0.036). Non-responders had lower pretreatment BPI (mean: 13.7 vs. 58.2; P = 0.032), with significantly higher values after 1 month (mean: 9.1 vs. 5.3, P = 0.033). Baseline BPI (OR: 1.17; 95% CI: 1.032-1.327; P = 0.014) and BPI at 1 month (OR: 0.83; 95% CI: 0.698-0.976; P = 0.025) were independent predictors of pain response at 3 months. Our findings show that palliative RT ensured short-term pain control in patients with BM, regardless of tumor type and dose-fractionation regimen. A larger sample size and a longer follow-up could potentially identify which patients are likely to benefit most from RT, and which fractionation might be indicated for achieving a durable pain relief. A multidisciplinary approach is paramount to provide a better care to BM patients.

Stereotactic body radiation therapy (SBRT) for spinal metastases: 12 years of a single center experience

OBJECTIVE

To assess the clinical outcomes of patients with spine metastases treated with SBRT at our institution.

MATERIALS AND METHODS

Patients with spine metastases treated with SBRT (1 fraction/18 Gy or 5 fractions/7 Gy) during the last 12 years have been analyzed. All patients were simulated supine in a vacuum cushion or with a shoulder mask. CT scans and MRI image registration were performed. Contouring was based on International Spine-Radiosurgery-Consortium-Consensus-Guidelines. Highly conformal-techniques (IMRT/VMAT) were used for treatment planning. Intra and interfraction (CBCT or X-Ray-ExacTrac) verification were mandatory.

RESULTS

From February 2010 to January 2022, 129 patients with spinal metastases were treated with SBRT [1 fraction/18 Gy (75%) or 5 fractions/7 Gy] (25%). For patients with painful metastases (74/129:57%), 100% experienced an improvement in pain after SBRT. With a median follow-up of 14.2 months (average 22.9; range 0.5-140) 6 patients (4.6%) experienced local relapse. Local progression-free survival was different, considering metastases's location (p < 0.04). The 1, 2 and 3 years overall survival (OS) were 91.2%, 85.1% and 83.2%, respectively. Overall survival was significantly better for patients with spine metastases of breast and prostate cancers compared to other tumors (p < 0.05) and significantly worse when visceral metastases were present (p < 0.05), when patients were metastatic de novo (p < 0.05), and in those patients receiving single fraction SBRT (p: 0.01).

CONCLUSIONS

According to our experience, SBRT for patients with spinal metastases was effective in terms of local control and useful to reach pain relief. Regarding the intent of the treatment, an adequate selection of patients is essential to propose this ablative approach.

Artificial intelligence-aided lytic spinal bone metastasis classification on CT scans

PURPOSE

Spinal bone metastases directly affect quality of life, and patients with lytic-dominant lesions are at high risk for neurological symptoms and fractures. To detect and classify lytic spinal bone metastasis using routine computed tomography (CT) scans, we developed a deep learning (DL)-based computer-aided detection (CAD) system.

METHODS

We retrospectively analyzed 2125 diagnostic and radiotherapeutic CT images of 79 patients. Images annotated as tumor (positive) or not (negative) were randomized into training (1782 images) and test (343 images) datasets. YOLOv5m architecture was used to detect vertebra on whole CT scans. InceptionV3 architecture with the transfer-learning technique was used to classify the presence/absence of lytic lesions on CT images showing the presence of vertebra. The DL models were evaluated via fivefold cross-validation. For vertebra detection, bounding box accuracy was estimated using intersection over union (IoU). We evaluated the area under the curve (AUC) of a receiver operating characteristic curve to classify lesions. Moreover, we determined the accuracy, precision, recall, and F1 score. We used the gradient-weighted class activation mapping (Grad-CAM) technique for visual interpretation.

RESULTS

The computation time was 0.44 s per image. The average IoU value of the predicted vertebra was 0.923 ± 0.052 (0.684-1.000) for test datasets. In the binary classification task, the accuracy, precision, recall, F1-score, and AUC value for test datasets were 0.872, 0.948, 0.741, 0.832, and 0.941, respectively. Heat maps constructed using the Grad-CAM technique were consistent with the location of lytic lesions.

CONCLUSION

Our artificial intelligence-aided CAD system using two DL models could rapidly identify vertebra bone from whole CT images and detect lytic spinal bone metastasis, although further evaluation of diagnostic accuracy is required with a larger sample size.

Optimal timing for local ablative treatment of bone oligometastases in non-small cell lung cancer

Oligometastases is a term commonly used to describe a disease state characterized by a limited number of distant metastases, and represents a transient phase between localized and widespread systemic diseases. This subgroup of stage IV cancer has increased in clinical importance due to the possibility of curative rather than palliative treatment. Among advanced lung cancer patients, 30-40% show bone metastases, and can show complications such as pathological fractures. Many prospective studies have shown efficacy of localized treatment in oligometastatic non-small cell lung cancer (NSCLC) in improving progression-free survival and overall survival. Compared to metastases in other organs, bone metastases are unique in terms of tumor microenvironment and clinical outcomes. Radiotherapy is the most frequently used treatment modality for local ablative treatment for both primary and metastatic lesions. Stereotactic body radiation therapy demonstrated more rapid and effective pain control compared to conventional 3D conformal radiotherapy. Radiotherapy improved outcomes in terms of time-to-skeletal related events skeletal-related events (SRE), hospitalization for SRE, pain relief, and overall survival in patients with bone metastases. Decision on timing of local ablative treatment depends on patient's overall clinical status, treatment goals, potential side effects of each approach, and expected initial responses to systemic anti-cancer treatment.

Comparison of Tumor Control After Stereotactic Radiosurgery or Pencil Beam Proton Therapy for Newly Diagnosed Clival Chordomas: A Single-Center Retrospective Study

OBJECTIVE

To compare outcomes of proton radiation therapy (PRT), stereotactic radiosurgery (SRS), and x-ray-based radiation with an SRS boost (XRT + SRS) for newly diagnosed clival chordoma.

METHODS

Consecutive patients who underwent PRT or SRS in our facility were retrospectively reviewed.

RESULTS

A total of 59 patients were identified (PRT, 36; SRS, 11; XRT + SRS, 12). The mean age (± standard deviation) was 46 ± 20 years, with 54% being male. The mean tumor diameter (± standard deviation) was 3.7 ± 1.5 cm, and 21 (36%) involved the lower clivus. Gross total or near-total resection was attained in 27 patients (46%), all of whom received PRT. PRT was administered with a median prescribed dose of 70.8 Gy (range, 66.0-76.0). SRS involved a median marginal dose of 16 Gy (range, 14-20) and a median maximal dose of 36 Gy (range, 30-45). The XRT + SRS group was treated with an SRS marginal dose of 12.5 Gy (range, 10-20), a maximal dose of 27 Gy (range, 20-40), and an XRT prescription dose of 50.4 Gy (range, 45.0-59.4). Fifteen recurrences were observed (PRT, 6; SRS, 5; XRT + SRS, 4). For the entire cohort (n = 59), recurrence was associated with the degree of resection (P = 0.042), but not with radiation groups (P = 0.98). For patients after subtotal resection or biopsy (n = 32), the SRS ± XRT group was associated with few recurrences (hazard ratio, 0.260; 95% confidence interval, 0.069-0.98; P = 0.046).

CONCLUSIONS

Patients after subtotal resection or biopsy may benefit from the incorporation of SRS.

Stressed target cancer cells drive nongenetic reprogramming of CAR T cells and solid tumor microenvironment

The poor efficacy of chimeric antigen receptor T-cell therapy (CAR T) for solid tumors is due to insufficient CAR T cell tumor infiltration, in vivo expansion, persistence, and effector function, as well as exhaustion, intrinsic target antigen heterogeneity or antigen loss of target cancer cells, and immunosuppressive tumor microenvironment (TME). Here we describe a broadly applicable nongenetic approach that simultaneously addresses the multiple challenges of CAR T as a therapy for solid tumors. The approach reprograms CAR T cells by exposing them to stressed target cancer cells which have been exposed to the cell stress inducer disulfiram (DSF) and copper (Cu)(DSF/Cu) plus ionizing irradiation (IR). The reprogrammed CAR T cells acquire early memory-like characteristics, potent cytotoxicity, enhanced in vivo expansion, persistence, and decreased exhaustion. Tumors stressed by DSF/Cu and IR also reprogram and reverse the immunosuppressive TME in humanized mice. The reprogrammed CAR T cells, derived from peripheral blood mononuclear cells of healthy donors or metastatic female breast cancer patients, induce robust, sustained memory and curative anti-solid tumor responses in multiple xenograft mouse models, establishing proof of concept for empowering CAR T by stressing tumor as a promising therapy for solid tumors.

Predictors of pathologic fracture and local recurrence following stereotactic body radiation therapy to 505 non-spine bone metastases

PURPOSE

Stereotactic Body Radiation Therapy (SBRT) is increasingly applied to treat non-spine bone metastases (NSBM) though data remains limited on this approach. In this retrospective study, we report outcomes and predictors of local failure (LF) and pathological fracture (PF) post-SBRT for NSBM using a mature single-institution database.

METHODS

Patients with NSBM treated with SBRT between 2011 and 2021 were identified. The primary objective was to assess the rates of radiographic LF. Secondary objectives were to assess the rates of in-field PF, overall survival (OS), and late grade ≥ 3 toxicity. Competing risks analysis was used to assess rates of LF and PF. Univariable regression and multivariable regression (MVR) were performed to investigate predictors of LF and PF.

RESULTS

A total of 373 patients with 505 NSBM were included in this study. Median follow-up was 26.5 months. The cumulative incidence of LF at 6, 12, and 24 months were 5.7%, 7.9%, and 12.6%, respectively. The cumulative incidence of PF at 6, 12, and 24 months were 3.8%, 6.1%, and 10.9%, respectively. Lytic NSBM (HR = 2.18; p < 0.01), a lower biologically effective dose (HR = 1.11 per 5 Gy10 decrease; p = 0.04), and a PTV ≥ 54 cc (HR = 4.32; p < 0.01) predicted for a higher risk of LF on MVR. Lytic NSBM (HR = 3.43; p < 0.01), mixed (lytic/sclerotic) lesions (HR = 2.70; p = 0.04), and rib metastases (HR = 2.68; p < 0.01) predicted for a higher risk of PF on MVR.

CONCLUSION

SBRT is an effective modality to treat NSBM with high rates of radiographic local control with an acceptable rate of PF. We identify predictors of both LF and PF that can serve to inform practice and trial design.

Deep learning-based detection of patients with bone metastasis from Japanese radiology reports

PURPOSE

Deep learning (DL) is a state-of-the-art technique for developing artificial intelligence in various domains and it improves the performance of natural language processing (NLP). Therefore, we aimed to develop a DL-based NLP model that classifies the status of bone metastasis (BM) in radiology reports to detect patients with BM.

MATERIALS AND METHODS

The DL-based NLP model was developed by training long short-term memory using 1,749 free-text radiology reports written in Japanese. We adopted five-fold cross-validation and used 200 reports for testing the five models. The accuracy, sensitivity, specificity, precision, and area under the receiver operating characteristics curve (AUROC) were used for the model evaluation.

RESULTS

The developed model demonstrated classification performance with mean ± standard deviation of 0.912 ± 0.012, 0.924 ± 0.029, 0.901 ± 0.014, 0.898 ± 0.012, and 0.968 ± 0.004 for accuracy, sensitivity, specificity, precision, and AUROC, respectively.

CONCLUSION

The proposed DL-based NLP model may help in the early and efficient detection of patients with BM.

Whole-body low-dose CT can be of value in prostate cancer decision-making: a retrospective study on 601 patients

OBJECTIVES

To evaluate the diagnostic value of whole-body low-dose computed tomography (CT) to detect bone metastasis in prostate cancer (PCa) patients and its possible utility in therapeutic decision-making. Also, to determine the valuable CT features for lesion characterisation.

METHODS

This IRB-approved retrospective study reviewed PCa patients who underwent ⁶⁸Ga-PSMA PET/CT in our centre from March 2017 to August 2022. Two board-certified radiologists and one nuclear medicine specialist reported all whole-body low-dose CT scans separately, unaware of the ⁶⁸Ga-PSMA-PET results. The per-lesion and per-patient diagnostic performances were calculated. Also, the significance of CT features was evaluated. Moreover, the inter-observer agreement was analysed. A two-tailed p value < 0.05 was considered significant.

RESULTS

From 727 reviewed PCa patients, 601 (mean age = 68.7 ± 8.1) were found to be eligible, including 211 (35.1%) referrals for initial staging and 390 (64.9%) for evaluating the extent of the disease after biochemical recurrence. Per-patient diagnostic analysis for three reviewers showed 81.0-89.4% sensitivity and 96.6-98.5% specificity in detecting osteo-metastasis. It was able to correctly detect high-burden disease based on both CHAARTED and LATITUDE criteria. Regarding the value of underlying CT features, size > 1 cm, ill-defined borders, presence of soft-tissue component, and cortical destruction were statistically in favour of metastasis. Also, Hu > 900 was in favour of benign entities with 93% specificity.

CONCLUSIONS

Although not as accurate as ⁶⁸Ga-PSMA PET/CT, whole-body low-dose CT might precisely classify PCa patients considering therapeutic decision-making. Additionally, we proposed diagnostic CT features that could help radiologists with better characterisation of the detected lesions.

CRITICAL RELEVANCE STATEMENT

The whole-body low-dose CT can be considered valuable in the clinical decision-making of prostate cancer patients. This modality may obviate performing multiple imaging sessions and high-cost scans in patients diagnosed with the high-burden disease.

Radiation combined with immune checkpoint inhibitors for unresectable locally advanced non-small cell lung cancer: synergistic mechanisms, current state, challenges, and orientations

Until the advent of immune checkpoint inhibitors (ICIs), definitive radiotherapy (RT) concurrently with chemotherapy was recommended for unresectable, locally advanced non-small cell lung cancer (LA-NSCLC). The trimodality paradigm with consolidation ICIs following definitive concurrent chemoradiotherapy has been the standard of care since the PACIFIC trial. Preclinical evidence has demonstrated the role of RT in the cancer-immune cycle and the synergistic effect of RT combined with ICIs (iRT). However, RT exerts a double-edged effect on immunity and the combination strategy still could be optimized in many areas. In the context of LA-NSCLC, optimized RT modality, choice, timing, and duration of ICIs, care for oncogenic addicted tumors, patient selection, and novel combination strategies require further investigation. Targeting these blind spots, novel approaches are being investigated to cross the borders of PACIFIC. We discussed the development history of iRT and summarized the updated rationale for the synergistic effect. We then summarized the available research data on the efficacy and toxicity of iRT in LA-NSCLC for cross-trial comparisons to eliminate barriers. Progression during and after ICIs consolidation therapy has been regarded as a distinct resistance scenario from primary or secondary resistance to ICIs, the subsequent management of which has also been discussed. Finally, based on unmet needs, we probed into the challenges, strategies, and auspicious orientations to optimize iRT in LA-NSCLC. In this review, we focus on the underlying mechanisms and recent advances of iRT with an emphasis on future challenges and directions that warrant further investigation. Taken together, iRT is a proven and potential strategy in LA-NSCLC, with multiple promising approaches to further improve the efficacy. Video Abstract.

Efficacy of ketamine mouthwash in the management of oral and pharyngeal toxicity associated with head and neck chemoradiotherapy: protocol for a phase II, Simon's two-stage trial

INTRODUCTION

Curative intent treatment of head and neck cancer (HNC) is frequently radiation therapy over 7 weeks with concurrent chemotherapy. This regimen is effective but carries a burden of toxicity leading to severe pain and treatment breaks portending inferior outcomes. Conventional palliation methods include opioids, anticonvulsants and local anaesthetics. Breakthrough toxicities are nevertheless ubiquitous and present an urgent unmet need. Ketamine is an inexpensive drug with mechanisms of analgesia outside the opioid pathway including N-methyl-D-aspartate (NMDA) receptor antagonism and a pharmacologically unique property of opioid desensitisation. Systemic ketamine is validated in randomised controlled trials for efficacy in reducing pain and/or opioid burden in the oncologic setting. Literature supports peripherally administered ketamine for pain control without systemic toxicity. These data support our rationale of using ketamine mouthwash to decrease acute toxicity of curative treatment of HNC, the efficacy of which is our aim to elucidate.

METHODS AND ANALYSIS

This is a phase II, Simon's two-stage trial. Patients have pathologically confirmed HNC and an intended regimen of 70 Gy of radiation with concurrent cisplatin. The protocol is initiated on diagnosis of grade 3 mucositis and consists of 2 weeks of 4 times daily (QID) ketamine mouthwash use. The primary endpoint is pain response defined as a combination of pain score and opioid use. 23 subjects will be enrolled in stage 1. If statistical criteria are met, 33 subjects will be enrolled in stage 2. Secondary endpoints include daily pain, daily opioid use, dysphagia at baseline and completion, nightly sleep quality, feeding tube placement and any unscheduled treatment breaks.

ETHICS AND DISSEMINATION

All trial data will be stored in an Institutional Review Board (IRB) approved database. The protocol is registered under Northwell IRB registration number #22-0292 and U.S. Food and Drug Administration (FDA) Investigational New Drug (IND) approval has been granted under IND number 161609. Results are intended to be published in an open-source journal and further data, statistics and source documents are available on request.

TRIAL REGISTRATION NUMBER

NCT05331131.

Radiation Therapy for Painful Bone Metastases: Fractionation, Recalcification, and Symptom Control

Bone is a common site for metastases, which may cause pain and other skeletal-related events (SRE) in patients with advanced cancer. Since the 1980s, prospective clinical trials have demonstrated the high efficacy of external beam radiotherapy (EBRT) for pain relief from focal, symptomatic lesions. In uncomplicated bone metastases, which include those without pathologic fracture, evidence of cord compression, or prior surgical intervention, improvement or complete pain relief with radiotherapy is as high as 60%, with no difference in efficacy when radiotherapy is delivered in a single or multiple fractions. The ability to treat with a single fraction makes EBRT an attractive therapy even for patients with poor performance status and/or life expectancy. Even in patients with complicated bone metastases (eg cord compression), several randomized trials have demonstrated similar rates of pain relief in addition to improved functional outcomes such as ambulation. In this review, we summarize the role of EBRT for alleviating painful bone metastases and explore its role for other endpoints including functional outcomes, recalcification, and prevention of SREs.

Radiation Therapy at the End of-Life: Quality of Life and Financial Toxicity Considerations

In patients with advanced cancer, radiation therapy is considered at various time points in the patient's clinical course from diagnosis to death. As some patients are living longer with metastatic cancer on novel therapeutics, radiation oncologists are increasingly using radiation therapy as an ablative therapy in appropriately selected patients. However, most patients with metastatic cancer still eventually die of their disease. For those without effective targeted therapy options or those who are not candidates for immunotherapy, the time frame from diagnosis to death is still relatively short. Given this evolving landscape, prognostication has become increasingly challenging. Thus, radiation oncologists must be diligent about defining the goals of therapy and considering all treatment options from ablative radiation to medical management and hospice care. The risks and benefits of radiation therapy vary based on an individual patient's prognosis, goals of care, and the ability of radiation to help with their cancer symptoms without undue toxicity over the course of their expected lifetime. When considering recommending a course of radiation, physicians must broaden their understanding of risks and benefits to include not only physical symptoms, but also various psychosocial burdens. These include financial burdens to the patient, to their caregiver and to the healthcare system. The burden of time spent at the end-of-life receiving radiation therapy must also be considered. Thus, the consideration of radiation therapy at the end-of-life can be complex and requires careful attention to the whole patient and their goals of care.

Multidisciplinary Approach to Spinal Metastases and Metastatic Spinal Cord Compression—A New Integrative Flowchart for Patient Management

Metastatic spine disease (MSD) and metastatic spinal cord compression (MSCC) are major causes of permanent neurological damage and long-term disability for cancer patients. The development of MSD is pathophysiologically framed by a cooperative interaction between general mechanisms of bone growth and specific mechanisms of spinal metastases (SM) expansion. SM most commonly affects the thoracic spine, even though multiple segments may be affected concomitantly. The great majority of SM are extradural, while intradural-extramedullary and intramedullary metastases are less frequently seen. The management of patients with SM is particularly complex and challenging, with multiple factors—such as the spinal stability status, primary tumor radio and chemosensitivity, cancer biological burden, patient performance status and comorbidities, and patient’s oncological prognosis—influencing the clinical decision-making process. Different frameworks were developed in order to systematize and support this process. A multidisciplinary, personalized approach, enriched by the expertise of each involved specialty, is crucial. We reviewed the most recent evidence and proposed an updated algorithmic approach to patients with MSD according to the clinical scenario of each patient. A flowchart-based approach offers an evidence-based management of MSD, providing a valuable clinical decision tool in a context of high uncertainty and quick-acting need.

Stereotactic Body Radiation Therapy Versus Conventional Radiation Therapy in Pain Relief for Bone Metastases: A Systematic Review and Meta-Analysis

PURPOSE

This study aimed to investigate the difference in pain relief between stereotactic body radiation therapy (SBRT) and conventional radiation therapy (cRT) for patients with bone metastases.

METHODS AND MATERIALS

Clinical trials and observational studies comparing SBRT versus cRT for bone metastases were retrieved. The main endpoint was pain relief after radiation therapy; the secondary endpoints were pain score change, local progression-free survival, reirradiation rate, and toxic events. When there was a significant heterogeneity, the random-effects model was applied. Otherwise, the fixed-effects model was used. Analyses of all included studies were performed first, followed by analyses of randomized controlled trials (RCTs) only.

RESULTS

Six RCTs, 1 prospective cohort study, and 3 retrospective observational studies were enrolled. Between 2004 and 2019, 448 patients received SBRT, and 445 patients received cRT. All prospective studies defined the lesions as oligometastatic. Pooled results based on all included studies indicated that SBRT was generally associated with a higher overall relief rate (P < .001 at 3 months; P = .015 at 6 months) and complete relief rate (P = .029 at 1 month; P < .001 at 6 months). Pooled results based on RCTs indicated that at 3 and 6 months, SBRT was associated with a higher overall relief rate (P < .001 and P = .017, respectively) and complete relief rate (P < .001 and P < .00, respectively). Subgroup analyses indicated that in more cases, the analgesic advantage of SBRT was more obvious when spinal lesions were irradiated, when the difference in the mean biological effective dose (BED) was less, or when intensity modulated radiation therapy was used to deliver SBRT.

CONCLUSIONS

Excessive elevation of BED introduces the risk of diminishing the analgesic effect of SBRT. SBRT delivered using intensity modulated radiation therapy is preferred for pain relief in spinal oligometastases. More RCTs are required to determine the most appropriate BED or dose regimen for SBRT.

Pain Response Rates After Conventional Radiation Therapy for Bone Metastases Assessed Using International Consensus Pain Response Endpoints: A Systematic Review and Meta-Analysis of Initial Radiation Therapy and Reirradiation

Previous meta-analysis of conventional radiation therapy for painful bone metastases showed overall response (OR) rates of 72% to 75% (evaluable patients), 61% to 62% (intent-to-treat patients) for initial radiation therapy, and 68% for reirradiation (evaluable patients). However, the definition of pain response differed among the studies included. Hence, we conducted a systematic review and meta-analysis to determine the pain response rates assessed by the International Consensus Pain Response Endpoints (ICPRE) for both initial radiation therapy and reirradiation. The PubMed and Scopus databases were searched for articles published between 2002 and 2021. The inclusion criteria were (1) prospective studies or studies based on prospectively collected data and (2) studies in which pain response was assessed using ICPRE. Our primary outcomes of interest were the OR rates (sum of the complete and partial response rates) for both initial radiation therapy and reirradiation. Of the 6470 articles identified in our database search, 32 and 3 met the inclusion criteria for the analysis of initial radiation therapy and reirradiation, respectively. The OR rates of initial radiation therapy in evaluable patients (n = 4775) and intent-to-treat patients (n = 6775) were 60.4% (95% confidence interval [CI], 55.2-65.4) and 45.4% (95% CI, 38.7-52.4), respectively. The OR rates of reirradiation in evaluable patients (n = 733) and intent-to-treat patients (n = 1085) were 70.8% (95% CI, 15.7-96.9) and 62.2% (95% CI, 5.3-98.0), respectively. Subgroup analyses of initial radiation therapy including the comparison of randomized and nonrandomized studies showed no significant differences in any comparison, indicating similar response rates across different study designs. For initial radiation therapy, we determined the ICPRE-assessed response rates, which were lower than previously reported. The OR and complete response rates should be benchmarks for future randomized and nonrandomized studies. For reirradiation, the wide CIs demonstrate that the response rates based on ICPRE require further investigation.

Effect of histology on stereotactic body radiotherapy for non-small cell lung cancer oligometastatic pulmonary lesions

Background

Stereotactic body radiotherapy (SBRT) is commonly used to provide targeted treatment to metastatic lung disease. Investigation is needed to understand the influence of histology on treatment outcomes. We report how tumor histology affects local control (LC) in a cohort of patients with non-small cell lung cancer (NSCLC) receiving SBRT for oligometastatic and recurrent pulmonary lesions.

Methods

Patients who received SBRT to recurrent or oligometastatic NSCLC pulmonary lesions from 2015-2019 at our institution were included in this retrospective cohort study. Minimum follow-up was 2 months. Kaplan-Meier (KM) analysis was performed to assess local progression-free survival (LPFS). Local failure cumulative incidence curves using death as a competing risk factor were also generated.

Results

A total of 147 treated lesions from 83 patients were included: 95 lesions from 51 patients with lung adenocarcinoma and 52 lesions from 32 patients with lung squamous cell carcinoma (SqCC). Median follow-up was 23 [interquartile range (IQR): 9.5-44.5] months for adenocarcinoma, and 11.5 (6-32.25) months for SqCC. Two-year LC was 89% for adenocarcinoma and 77% for SqCC (P=0.04). Median overall survival (OS) was 24.5 (10-46.25) months for adenocarcinoma and 14.5 (7.75-23.25) months for SqCC. Adenocarcinoma had improved LPFS over SqCC (P=0.014). SqCC was associated with increased local failure risk that approached statistical significance (P=0.061) with death as a competing risk. Overall toxicity incidence was 8.2% with no G3+ toxicities.

Conclusions

For SBRT-treated oligometastatic or recurrent NSCLC pulmonary lesions, adenocarcinoma histology is associated with improved 2-year LC and LPFS compared to SqCC and reduced incidence of local recurrence (LR) with death as a competing risk.

Palliative extracranial radiotherapy in patients receiving immunotherapy for non-small cell lung cancer: a narrative review

Background and Objective

Role of radiotherapy (RT) in the era of immuno-oncology (IO) in advanced non-small cell lung cancer (NSCLC) is rapidly changing. RT is not only intended for addressing palliation symptoms but also is considered as a potential tool potentializing an immunogenic effect of given drugs. However, the best timing, techniques, doses, volumes, and its use for asymptomatic patients is a subject of research. We performed a review on the role of palliative RT schedules in combination with IO for advanced NSCLC. Indications in symptomatic and asymptomatic patients, outcomes, toxicity, and possible developments are discussed.

Methods

A literature search was conducted in MEDLINE and PubMed databases and clinicaltrials.gov using the keywords 'lung cancer' AND "immunotherapy" AND 'radiotherapy' OR "palliative radiotherapy".

Key Content and Findings

Body of evidence indicate that palliative RT used in combination with IO is effective in terms of symptom management and safe; does not increase the risk of serious side effects, including serious pulmonary toxicity. We have limited data evidencing improvement of survival by addition of short ablative RT dose to one site of the disease to IO in oligometastatic NSCLC. Some data indicate that short ablative doses of stereotactic body radiation therapy (SBRT) are more effective with regard to treatment response and survival than protracted RT schedule with lower fractional doses. However, this may be a selection bias of better prognostic patients who underwent SBRT. The use of steroids being a potential concern during IO should not be prohibited if clinically indicated during palliative RT. Its detrimental effect shown in some studies may also be a result of selection bias, because steroids given for not cancer-related causes during IO did not decrease survival.

Conclusions

RT for symptom management may be used during, directly before or after IO. This has a potential to ease symptom burdens and improve performance status (PS). However, still more studies are needed to establish optimal guidelines in asymptomatic patients for appropriate timing, volumes, dose, and fractionation schedules of palliative RT use in combination with IO.

Ductal prostate cancer: Clinical features and outcomes from a multicenter retrospective analysis and overview of the current literature

Objective

The aim of the study is to evaluate clinical features and outcomes after different therapeutic strategies for ductal prostate adenocarcinoma (DPC), a rare but aggressive subtype of invasive prostate cancer (PCa) accounting for, in the pure and mixed form, 1% or less and 5% or less, respectively, of all the newly diagnosed PCa.

Materials and methods

Patients with a proven diagnosis of DPC undergoing surgery, radiotherapy, and androgen deprivation therapy, alone or in combination, were considered for this multicenter, retrospective study. The study assessed overall survival (OS), disease-free survival (DFS), and age-related disease-specific survival.

Results

Eighty-one patients met the study inclusion criteria. Pure DPC was found in 29 patients (36%) and mixed ductal-acinar-PCa in 52 patients (64%). After a median follow-up of 63 months (range, 3-206 months), 3- and 5-year OS rates were 84% and 67%, respectively, and 3- and 5-year DFS rates were 54% and 34%, respectively. There were no significant differences in OS or DFS between the pure and mixed DPC groups. Pure DPC was associated with a higher rate of metastatic disease at onset. Patients 74 years or younger had better disease-specific survival (p=0.0019). A subgroup analysis favored radiotherapy as the primary treatment for nonmetastatic, organ-confined DPC (3- and 5-year DFS of 80% and 50%, respectively, compared with 5-year DFS of 35% for surgical patients; p = 0.023).

Conclusions

Our study found DPC to be rarer, more aggressive, more likely to metastasize, and have a worse prognosis than the common acinar variant, especially in its pure form. Multicenter series are encouraged to obtain large data sets, or propensity score matching analyses with patients with conventional PCa are desirable to understand the best therapeutic approach and improve outcomes.

Efficacy and safety of stereotactic body radiotherapy for painful bone metastases: Evidence from randomized controlled trials

Background

Pain relief is one of the main objectives of radiotherapy for cancer patients with bone metastases. Stereotactic body radiotherapy (SBRT) enables precise delivery of a higher dosage to the target area. Several trials have reported comparisons between SBRT and conventional radiotherapy (cRT) in patients with painful bone metastasis. However, the results of those investigations were inconsistent, and no systematic review or meta-analysis has been done till now.

Methods

We systematically searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and Clinicaltrials.gov up to May 1, 2022 for relevant studies. Patients with painful bone metastasis who received SBRT or cRT were included. The primary outcome was the patients’ pain response rate at three months. The secondary outcomes included the rate of pain responders at one month and six months, oral morphine equivalent dose (OMED) use, and any adverse events. STATA software 12.0 was used for the statistical analysis.

Results

We collected 533 patients’ data from 4 randomized controlled trials (RCTs), there was a significant difference of pain response rate at 3 months between two groups (RR = 1.41, 95% CI: 1.12-1.77, I2 = 0.0%, P = 0.003). However, no significant difference was found in pain response rate at 1 month (RR = 1.19, 95% CI: 0.91-1.54, I2 = 31.5%, P = 0.201) and 6 months (RR = 1.25, 95% CI: 0.93-1.69, I2 = 0.0%, P = 0.140). OMED consumption was not significantly different in patients treated with SBRT compared with control group (WMD = -1.11, 95% CI: -17.51-15.28, I2 = 0.0%, P = 0.894). For safety outcome, no statistical difference was found between SBRT and cRT (RR = 0.72, 95% CI: 0.46-1.14, I2=20.1%, P = 0.162).

Conclusion

This study shows that for painful bone metastases, patients with SBRT experienced better pain relief 3 months after radiation than patients with cRT, and SBRT did not increase the incidence of adverse events.

Systematic review registration

https://inplasy.com/inplasy-2022-6-0099/, identifier INPLASY202260099.

Stereotactic body radiotherapy versus conventional radiotherapy for painful bone metastases: a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Stereotactic body radiotherapy (SBRT) is a promising approach in treating painful bone metastases. However, the superiority of SBRT over conventional external beam radiotherapy (cEBRT) remains controversial. Therefore, this systematic review and meta-analysis of randomised controlled trials was conducted to compare SBRT and cEBRT for the treatment of bone metastases.

METHODS

A search was conducted using PubMed on January 22, 2022, with the following inclusion criteria: (i) randomised controlled trials comparing SBRT with cEBRT for bone metastases and (ii) endpoint including pain response. Effect sizes across studies were pooled using random-effects models in a meta-analysis of risk ratios.

RESULTS

A total of 1246 articles were screened, with 7 articles comprising 964 patients (522 and 442 patients in the SBRT and cEBRT arms, respectively) meeting the inclusion criteria. The overall pain response (OR) rates of bone metastases at 3 months were 45% and 36% in the SBRT and cEBRT arms, respectively. The present analyses showed no significant difference between the two groups. In four studies included for the calculation of OR rates of spinal metastases at three months, the OR rates were 40% and 35% in the SBRT and cEBRT arms, respectively, with no significant difference between the two groups. The incidence of severe adverse effects and health-related quality of life outcomes were comparable between the two arms.

CONCLUSIONS

The superiority of SBRT over cEBRT for pain palliation in bone metastases was not confirmed in this meta-analysis. Although SBRT is a standard of care for bone metastases, patients receiving SBRT should be selected appropriately.

Palliative Efficacy of High-Dose Stereotactic Body Radiotherapy Versus Conventional Radiotherapy for Painful Non-Spine Bone Metastases: A Propensity Score-Matched Analysis

(1) Background: The superiority of stereotactic body radiotherapy (SBRT) over conventional external beam radiotherapy (cEBRT) in terms of pain palliation for bone metastases remains controversial. (2) Methods: This propensity score-matched study compared the overall pain response (OR) 3 months after radiotherapy among patients with painful (≥2 points on a 0-to-10 scale) non-spine bone metastases. Patients with lesions that were treated with SBRT or cEBRT and whose pain scores were evaluated 3 months after radiotherapy were included in this study. Pain response was evaluated according to the International Consensus Criteria. (3) Results: A total of 234 lesions (SBRT, n = 129; cEBRT, n = 105) were identified in our institutional database. To reduce the confounding effects, 162 patients were selected using a propensity score-matched analysis (n = 81 for each treatment). The OR rate at 3 months after SBRT was significantly higher than that after cEBRT (76.5% vs. 56.8%; p = 0.012). A noteworthy finding of our study is that the same trend was observed even after 6 months (75.9% vs. 50.0%; p = 0.011). The 1-year local failure rates after SBRT and cEBRT were 10.2% and 33.3% (p < 0.001), respectively. (4) Conclusions: Our findings suggest that SBRT is superior to cEBRT for pain palliation in patients with non-spine bone metastases.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with prostate cancer

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of prostate cancer was published in 2020. It was therefore decided, by both the ESMO and the Singapore Society of Oncology (SSO), to convene a special, virtual guidelines meeting in November 2021 to adapt the ESMO 2020 guidelines to take into account the differences associated with the treatment of prostate cancer in Asia. These guidelines represent the consensus opinions reached by experts in the treatment of patients with prostate cancer representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with prostate cancer across the different regions of Asia.

Stereotactic Body Radiation Therapy versus Conventional External Beam Radiation Therapy for Painful Bone Metastases: A Systematic Review and Meta-analysis of Randomized Trials

PURPOSE

To compare the efficacy and safety of stereotactic body radiation therapy (SBRT) and conventional external beam radiation therapy (cEBRT) in patients with previously unirradiated painful bone metastases (BM).

METHODS

We searched biomedical databases for eligible randomized trials (RCTs). The outcomes of interest were pain response, local progression, overall survival (OS) and adverse events. We used established tools to assess the quality of the individual trials and certainty of the pooled evidence. We performed meta-analyses using random effects models.

RESULTS

Six RCTs were identified. SBRT improved complete pain response rates at 3 months (OR, 3.38; 95% CI, 1.88-6.07; high certainty), reduced local progression rates (OR, 0.19; 95% CI, 0.06-0.62; high certainty) and increase pain flare rates. There were no differences for other outcomes.

CONCLUSION

Among patients with previously unirradiated painful BM, SBRT significantly improved complete pain response rates at 3 months, delayed local progression and increase pain flare rates.

STEREOTACTIC BODY RADIATION THERAPY FOR METASTASES IN LONG BONES

OBJECTIVE

To evaluate the cumulative incidence of fracture and local failure and associated risk factors after stereotactic body radiotherapy (SBRT) for long bone metastases.

MATERIAL AND METHODS

Data from 111 patients with 114 metastases in the femur, humerus and tibia treated with SBRT in 7 international centers between October 2011 and February 2021 were retrospectively reviewed and analyzed using a competing risk regression model.

RESULTS

The median follow-up was 21 months (range 6-91 months). All but one patient had a Karnofsky performance status ≥70. There were 84 femur (73.7%), 26 humerus (22.8%) and 4 tibia (3.5%) metastases from prostate (45 [39.5%]), breast (22 [19.3%]), lung (15 [13.2%]), kidney (13 [11.4%]) and other (19 [16.6%]) malignancies. Oligometastases accounted for 74.8% of metastases and 28.1% were osteolytic. The most common total doses were 30-50 Gy in 5 daily fractions (50.9%). Eight fractures (5 in the femur, 2 in the tibia and 1 in the humerus) were observed with a median time to fracture of 12 months (range 0.8-33 months). In 6/8 patients, fracture was not associated with local failure. The cumulative incidence of fracture was 3.5%, 6.1% and 9.8% at 1, 2 and 3 years, respectively. The cumulative incidence of local failure (9/110 metastases with imaging follow-up) was 5.7%, 7.2% and 13.5% at 1, 2 and 3 years, respectively. On multivariate analysis, extraosseous disease extension was significantly associated with fracture (P=0.001; subhazard ratio [SHR] 10.8; 95% CI 2.8-41.9) and local failure (P=0.02; SHR 7.9; 95% CI 1.4-44.7).

CONCLUSION

SBRT for metastases in long bones achieved high rates of durable local metastasis control without an increased risk of fracture. Similar to spine SBRT, patients with extraosseous disease extension are at higher risk of local failure and fracture.

Patient and Treatment Factors Associated with Improved Local Control and Survival in Oligometastatic Bone Disease: Results from a Large Single-Institution Experience Using Stereotactic Body Radiation Therapy

PURPOSE

Limited data exists to guide optimal patient selection and treatment of bone metastases with curative intent despite the increasing application of stereotactic body radiation therapy (SBRT) for oligometastatic (OM) disease control and re-irradiation(ReRT).

METHODS

Clinical characteristics for 434 patients consecutively treated with bone SBRT at a single institution from 3/2011-6/2020 were analyzed by OM, spine, and non-spine bone using Cox regression to determine association with local control (LC), progression-free survival (PFS), and overall survival (OS), and the Kaplan-Meier method to estimate PFS and OS.

RESULTS

Most patients had prostate (39%) or breast/lung (21%) cancer and 1-3 lesions (96%), with 651 lesions (spine 63%) treated for ReRT (12%) or OMD (88%), including synchronous (10%), metachronous (28%), repeat (27%), or induced (23%) states as defined by ESTRO/EORTC criteria. Biologically effective dose (BED₁₀) ≥50 (HR 0.68, CI 0.48-0.96, p<0.03) predicted improved LC among OM lesions and planning target volume (PTV)≥150 cc (HR 1.94, CI 1.02 to 3.70, p<0.04) predicted worse LC for non-spine bone. Prostate histology, performance status (PS) 0-1, and MFI ≥2 year predicted improved PFS and OS (p<0.05). Metachronous, synchronous, or repeat OM had higher PFS and OS (p≤0.001) than induced OM. With median follow-up 25.7 months, 1 and 2-year PFS was 63% and 47% for OM and 36% and 25% for ReRT;1 and 2-yr OS was 87% and 73% for OM, 58% and 43% for ReRT. Acute toxicities included grade 1-2 pain flare (9%) and fatigue (14%). Late toxicities included fracture (1%) for OM and myelopathy (2.5%) or nerve pain (1.2%) for ReRT.

CONCLUSIONS

BED₁₀ ≥ 50 for OM and PTV<150cc for non-spine bone lesions was associated with improved LC. Prostate histology, PS 0-1, MFI≥2 years, and metachronous, synchronous, or repeat presentations per EORTC/ESTRO OM criteria predicted improved PFS and OS among OM patients treated with bone SBRT.

Practice changing data and emerging concepts from recent radiation therapy randomised clinical trials

INTRODUCTION

Oncology treatments are constantly and rapidly evolving. We aimed at highlighting the latest radiation therapy practice changing trials and emerging concepts, through an overview of recent randomised clinical trials (RCTs).

MATERIALS AND METHODS

Requests were performed in the Medline database to identify all publications reporting radiation therapy RCTs from 2018 to 2021.

RESULTS

Recent RCTs sustained the role of newer combinatorial strategies through radioimmunotherapy for early stage or metastatic lung cancer, newer pro-apoptotic agents (e.g. debio 1143 in locoregionally advanced head and neck squamous cell carcinoma) or nanoparticles (e.g. NBTXR3 in locally advanced soft-tissue sarcoma). High-tech radiotherapy allows intensifying treatments and gaining ground in some indications through the development of stereotactic body radiotherapy for example. First randomised evidence on personalised radiation therapy through imaging-based (¹⁸FDG positron emission tomography-computed tomography for lung cancer or early stage unfavourable Hodgkin lymphoma, PMSA positron emission tomography-computed tomography or magnetic resonance imaging for high-risk prostate cancer) or biological biomarkers (PSA for prostate cancer, HPV for head and neck cancer, etc) were conducted to more tailored treatments, with more favourable outcomes. Patients' quality of life and satisfaction appeared to be increasing aims. RCTs have validated (ultra)hypofractionated schemes in many indications as for breast, prostate or rectal cancer, resulting in equivalent outcomes and toxicities, more convenient for patients and favouring shared decision making.

CONCLUSION

Radiation therapy is a dynamic field of research, and many RCTs have greatly impacted therapeutic standards over the last years. Investments in radiotherapy research should facilitate the transfer of innovation to clinic.

ESTRO ACROP guidelines for external beam radiotherapy of patients with uncomplicated bone metastases

After liver and lungs, bone is the third most common metastatic site (Nystrom et al., 1977). Almost all malignancies can metastasize to the skeleton but 80% of bone metastases originate from breast, prostate, lung, kidney and thyroid cancer (Mundy, 2002). Introduction of effective systemic treatment in many cancers has prolonged patients' survival, including those with bone metastases. Bone metastases may significantly reduce quality of life due to related symptoms and possible complications, such as pain and neurologic compromise. The most serious complications of bone metastases are skeletal-related events (SRE), defined as pathologic fracture, spinal cord compression, pain, or other symptoms requiring an urgent intervention such as surgery or radiotherapy. In turn, growing access to modern diagnostic tools allows early detection of asymptomatic bone metastases that could be successfully managed with local treatment avoiding development of SRE. The treatment for bone metastases should focus on relieving existing symptoms and preventing new ones. Radiotherapy is the standard of care for patients with symptomatic bone metastases, providing durable pain relief with minimal toxicity and reasonable cost-effectiveness. Historically, the dose was prescribed in one to five fractions and delivered using simple planning techniques. While 3D-conformal radiotherapy is still widely used for treating bone metastases, introduction of highlyconformal radiotherapy techniques such as stereotactic body radiotherapy (SBRT) have opened new therapeutic possibilities that should be considered in selected patients with bone metastases.

Local Therapies in Advanced Colorectal Cancer

Curative intent surgical resection of colorectal metastases to the liver and lungs in eligible patients results in improved disease control and prolonged overall survival with the potential for cure in a subset of patients. Additional ablative and local therapies for use in the liver, lungs, and other body sites have been developed with emerging data on the utility and toxicity of these treatments. Future studies should focus on identification of appropriate candidates for treatment and determining the optimal modality and timing of treatment accounting for both patient and disease factors.

Stereotactic Body Radiation Therapy (SBRT) for Spinal Metastases: Real-world Outcomes From an International Multi-institutional SBRT Registry

OBJECTIVE

The objective of this study was to compare clinical outcomes following single fraction versus fractionated stereotactic body radiotherapy (SBRT) for spinal metastases.

MATERIALS AND METHODS

A multi-institutional registry was queried for patients with spinal metastases treated with single-fraction or fractionated SBRT. Potential predictive factors of local control (LC) and overall survival were evaluated. Pretreatment and posttreatment Visual Analog Scale scores were analyzed to examine initial and durable pain responses and complete response (CR) rates. Logistic regression was utilized to assess potential correlations between pain response, biologically effective dose (BED), and fractionation.

RESULTS

Four hundred sixty-six patients with 514 lesions treated with SBRT were identified; 209 and 104 lesions had information on LC and pain, respectively. The median pain score of patients with symptoms was 6 (range: 3 to 10). The median follow-up was 8.9 months (range: 0.4 to 125.5 mo). Utilizing Karnofsky Performance Score, age, and primary site (lung and/or nonbreast), 1-year overall survival rates were 76.1%, 59.1%, 54.9%, 37.2%, and 23.5% for patients with 0 to 4 of these factors, respectively (P<0.0001). One- and 2-year LC rates were 79.9% and 73.6%, respectively. Eighty-six patients (82.7%) had an initial pain response with a median decline of 3.5 and a CR rate of 47.1%. Sixty-five patients (62.5%) had a durable pain response with a median decline of 2 and a CR rate of 20.2%. Higher initial CR rates were observed with BED10 ≥51 Gy10 (58.7% vs. 37.9%; P=0.04).

CONCLUSIONS

Following SBRT, encouraging palliative responses with >80% and 60% of patients having initial and durable pain responses, respectively. Dose escalation may result in improved initial CR rates. Performance status, age, and primary histology are factors to consider in the absence of pain.

A single arm phase II study of bone-targeted Sn-117 m-DTPA in symptomatic castration-resistant prostate cancer with skeletal metastases

BACKGROUND

Several bone-seeking radionuclides have been developed for palliation of metastatic bone pain since 1956, however, so far radium-223 dichloride is the first and only Food and Drug Administration (FDA) approved targeted alpha therapy for metastatic castration-resistant prostate cancer (mCRPC) based on ALSYMPCA phase 3 study. While radium-223 does improve pain and overall survival outcomes, the improvement can come at the expense of side effects such as bone marrow toxicity. The development of new and better treatment with long-standing pain relief is clearly an unmet medical need.

METHODS

The study is a non-randomized phase II study. The study population consists of 25 patients with CRPC who had progressed on any lines of prior therapies and whose serum testosterone level is less than 50 ng/dl and have metastatic lesions to at least two bone sites, with at least one site that has clinically meaningful pain at baseline (≥ 4 on an 11-point intensity scale). Eligible patients will be given two cycles of Sn-117 m-DTPA every 8 weeks or 56 days. Treatment will be administered by slow IV injection over 5-10 min. Retreatment after two cycles is allowed if patients meet the following retreatment criteria. The primary objective is to evaluate the efficacy of Sn-117 m-DTPA on sustained pain response in patients with CRPC metastatic to at least two bone sites and at least one with clinically meaningful pain at baseline (≥ 4 on an 11-point pain intensity scale). Sustained pain response is defined as: 1) achieving pain index ≤ 3 within a 12-week period and 2) maintaining pain index ≤ 3 over a 16-week period. The secondary objectives are: safety and tolerability, measurement of Sn-117 m-DTPA activity by gamma-camera dosimetry scans, therapeutic efficacy, time to the first symptomatic skeletal event, duration of pain response, changes in PSA and ALP levels, patient-reported outcomes and progression free survival and overall survival.

DISCUSSION

Sn-117 m-DTPA is a unique bone-targeting theranostic radiopharmaceutical agent that selectively binds most heavily to bone metastases sites. This study will be the first prospective phase II trial to assess the pain efficacy and anti-tumor activity of Sn-117 m-DTPA in mCRPC with at least one clinically meaningful pain at baseline.

TRIAL REGISTRATION

ClincialTrials.gov Identifier: NCT04616547.

Multidisciplinary Treatment of Non-Spine Bone Metastases: Results of a Modified Delphi Consensus Process

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Evidence is emerging for new paradigms in the management of non-spine bone metastases.

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Consensus was feasible amongst physicians in both academic and community-based practice settings.

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Topics deemed of highest importance for consensus included referral for surgical stabilization and approach to peri-operative radiation, preferred radiation fractionation and appropriate use of stereotactic techniques, and clinical scenarios classified as potentially “complex” warranting multidisciplinary discussion.

Purpose

Methods and Materials

Results

Conclusions