Palliative Radiotherapy For Bone Metastases Research Articles

The role of FDG uptake to predict the need for re-irradiation in patients treated with 8 Gy (X-ray) single fraction palliative radiotherapy for bone metastases

The role of FDG uptake to predict the need for re-irradiation in patients treated with 8 Gy (X-ray) single fraction palliative radiotherapy for bone metastases

Comparison of pain-relieving effects by number of irradiations, through propensity score matching and the international consensus endpoint.

Palliative radiotherapy for bone metastases utilizes various dose fractionation schedules. The pain-relieving effects of a single fraction (SF) and multiple fractions (MF) are largely debated due to the difficulty in matching patients' backgrounds and in assessing the effectiveness of pain relief. This study aimed to compare the pain-relieving effects of SF and MF palliative radiotherapy for bone metastases using propensity score matching and the international consensus endpoint (ICE). Our study included 195 patients irradiated for bone metastasis. The primary endpoint was the pain-relieving effects used by ICE. In addition, the evaluation was performed by using responder (complete response/partial response) and non-responder (pain progression/indeterminate response) categorization. The secondary endpoints were the discharge or transfer rate at one month after irradiation and postirradiation pathological fracture rate. Propensity score matching was used to adjust patient's characteristics and reduce selection bias. After adapting propensity score matching, the total number of patients was 74. There was no significant difference in the pain-relieving effects between SF and MF (p = 0.184). There were no significant differences in them between SF and MF when using responder and non-responder categorization (p = 0.163). Furthermore, there were no differences in the discharge or transfer rates (p = 0.693) and pathological fracture rates (p = 1.00). The combination of propensity score matching and ICE revealed no significant difference in the pain-relieving effects between SF and MF for bone metastases, thus, SF has no significant disadvantage compared to MF in pain-relieving effects.

Factors Associated with Long-Term Prostate Cancer Survival after Palliative Radiotherapy to a Bone Metastasis and Contemporary Palliative Systemic Therapy: A Retrospective, Population-Based Study

Background: Radiation therapy (RT) is an established palliative treatment for bone metastases; however, little is known about post-radiation survival and factors which impact it. The aim of this study was to assess a population-based sample of metastatic prostate cancer patients receiving palliative radiation therapy to bone metastases and contemporary palliative systemic therapy and identify factors that impact long-term survival. Materials/methods: This retrospective, population-based, cohort study assessed all prostate cancer patients receiving palliative RT for bone metastases at a Canadian provincial Cancer program during a contemporary time period. Baseline patient, disease, and treatment characteristics were extracted from the provincial medical physics databases and the electronic medical record. Post-RT Survival intervals were defined as the time interval from the first fraction of palliative RT to death from any cause or date of the last known follow-up. The median survival of the cohort was used to dichotomize the cohort into short- and long-term survivors following RT. Univariable and multivariable hazard regression analyses were performed to identify variables associated with post-RT survival. Results: From 1 January 2018 until 31 December 2019, 545 palliative RT courses for bone metastases were delivered to n = 274 metastatic prostate cancer patients with a median age of 76 yrs (Interquartile range (IQR) 39–83) and a median follow-up of 10.6 months (range 0.2 to 47.9). The median survival of the cohort was 10.6 months (IQR 3.5–25 months). The ECOG performance status of the whole cohort was ≤2 in n = 200 (73%) and 3–4 in n = 67 (24.5%). The most commonly treated sites of bone metastasis were the pelvis and lower extremities n = 130 (47.4%), skull and spine n = 114 (41.6%), and chest and upper extremities n = 30 (10.9%). Most patients had CHAARTED high volume disease n = 239 (87.2%). On multivariable hazard regression analysis, an ECOG performance status of 3–4 (p = 0.02), CHAARTED high volume disease burden (p = 0.023), and non-receipt of systemic therapy (p = 0.006) were significantly associated with worse post-RT survival. Conclusion: Amongst metastatic prostate cancer patients treated with palliative radiotherapy to bone metastases and modern palliative systemic therapies, ECOG performance status, CHAARTED metastatic disease burden, and type of first-line palliative systemic therapy were significantly associated with post-RT survival durations.

Time to Pain Relapse After Palliative Radiotherapy for Bone Metastasis: A Prospective Multi-institutional Study.

Low risk asymptomatic bone metastasis (LRABM) without gross osteolytic changes tends to be out of indication for radiotherapy. The aim of this study was to evaluate the time between the end of palliative radiotherapy of bone metastasis (BM) until the start of new pain, in patients with painful BM. Patients with BM were prospectively assessed for location and strength of pain every month for one year after radiotherapy. The correlation of pain relapse at irradiated site, and pain onset outside the irradiated site was evaluated with sex, age, primary tumor, pathology of tumor, visceral metastases, baseline scores for Eastern Cooperative Oncology Group performance status (PS), and baseline verbal rating scale (VRS). A hundred and thirty-two patients were included (79 males and 53 females). Median age was 66 years. Primary sites were lung (n=60), breast (n=17), colon (n=12), prostate (n=11), and others (n=33) (one patient had two primary sites). Median follow-up was 185 days. Pain relief was observed in 92 patients (86.0%). Out of them, pain progression was observed in 69.6%. Median time to pain progression was 75.5 days. Pain onset outside the irradiated site was observed in 57 patients (43.2%). Median time to pain onset was 109 days. Out of the 57 patients, 13 (22.8%) had LRABM which existed before the start of radiotherapy. There were 54 patients with LRABM in this study and because many patients had more than one LRABM, the total LRABM sites were 123. Out of them, pain onset was observed within one year after irradiation in 44 (36%) lesions. Median time to pain onset was 67 days, which was the shortest of the three: irradiated site, out of the irradiated site, and LRABM site. Risk factors for high probability of pain onset within one year in LRABM lesions were female sex (showing a trend in univariate analysis), and pelvic, skull and spine metastasis (significant in multivariate analysis). Time to pain onsets in LRABM are relatively short, especially in female patients with pelvic, skull and spine metastasis. In these patients, prophylactic radiotherapy could be an option to consider.

Independent Validation of a Risk Stratification Model Predicting Survival in Elderly Patients Irradiated for Bone Metastases.

Many patients with bone metastases receive palliative radiotherapy. However, treatment personalization tools are needed, due to heterogeneous survival. The aim of this study was to analyze the validity of the prognostic survival model, originally developed by Rades et al., because international variations in clinical practice and survival outcomes may impact on the performance of predictive tools. Data from a single institution were retrospectively analyzed. The study included 305 patients managed with palliative radiotherapy for bone metastases. The Rades et al. score was assigned and the resulting 3 prognostic strata were compared. The median overall survival for the 3 strata was 48, 248, and 1065 days, respectively (p<0.001). However, the original break-down (17 points versus 18-25 points versus >25 points) was not in accordance with the overlapping survival curves in some of the subgroups, leading us to propose slight adjustments. The modified model also performed satisfactorily in older patients (age ≥80 years; median survival 26, 192 and 489 days, respectively, p<0.001). The original Rades et al. survival score was a valid prognostic model in our Norwegian validation database. However, inclusion of patients with 18 points into the poor prognosis group is suggested as a modification to enhance the score's performance.

Phase Ib/II study of nivolumab combined with palliative radiation therapy for bone metastasis in patients with HER2-negative metastatic breast cancer

Radiation therapy (RT) can enhance the abscopal effect of immune checkpoint blockade. This phase I/II study investigated the efficacy and safety of nivolumab plus RT in HER2-negative metastatic breast cancer requiring palliative RT for bone metastases. Cohort A included luminal-like disease, and cohort B included both luminal-like and triple-negative disease refractory to standard systemic therapy. Patients received 8 Gy single fraction RT for bone metastasis on day 0. Nivolumab was administered on day 1 for each 14-day cycle. In cohort A, endocrine therapy was administered. The primary endpoint was the objective response rate (ORR) of the unirradiated lesions. Cohorts A and B consisted of 18 and 10 patients, respectively. The ORR was 11% (90% CI 4–29%) in cohort A and 0% in cohort B. Disease control rates were 39% (90% CI 23–58%) and 0%. Median progression-free survival was 4.1 months (95% CI 2.1–6.1 months) and 2.0 months (95% CI 1.2–3.7 months). One patient in cohort B experienced a grade 3 adverse event. Palliative RT combined with nivolumab was safe and showed modest anti-tumor activity in cohort A. Further investigations to enhance the anti-tumor effect of endocrine therapy combined with RT plus immune checkpoint blockade are warranted.Trial registration number and date of registration UMIN: UMIN000026046, February 8, 2017; ClinicalTrials.gov: NCT03430479, February 13, 2018; Date of the first registration: June 22, 2017.

Evaluation of a workflow for cone-beam CT-guided online adaptive palliative radiotherapy planned using diagnostic CT scans.

Single-visit radiotherapy (RT) is beneficial for patients requiring pain control and can limit interruptions to systemic treatments. However, the requirement for a dedicated planning CT (pCT)-scan can result in treatment delays. We developed a workflow involving preplanning on available diagnostic CT (dCT) imaging, followed by online plan adaption using a cone-beam CT (CBCT)-scan prior to RT-delivery, in order to account for any changes in anatomy and target position. Patients previously treated with palliative RT for bone metastases were selected from our hospital database. Patient dCT-images were deformed to treatment CBCTs in the Ethos platform (Varian Medical Systems) and a synthetic CT (sCT) generated. Treatment quality was analyzed by comparing a coverage of the V95% of the planning/clinical target volume and different organ-at-risk (OAR) doses between adapted and initial clinical treatment plans. Doses were recalculated on the CBCT and sCT in a separate treatment planning system. Adapted plan doses were measured on-couch using an anthropomorphic phantom with a Gafchromic EBT3 dosimetric film and compared to dose calculations. All adapted treatment plans met the clinical goals for target and OARs and outperformed the original treatment plans calculated on the (daily) sCT. Differences in V95% of the target volume coverage between the initial and adapted treatments were <0.2%. Dose recalculations on CBCT and sCT were comparable, and the average gamma pass rate (3%/2mm) of dosimetric measurements was 98.8%. Online daily adaptive RT using dCTs instead of a dedicated pCT is feasible using the Ethos platform. This workflow has now been implemented clinically.

Dexamethasone Coanalgesic Administration in Steroid Naïve and Steroid Non-Naïve Patients for the Prevention of Pain Flares after Palliative Radiotherapy for Bone Metastases.

Dexamethasone could be an effective prophylactic agent for the prevention of pain flares after palliative radiotherapy (RT) for uncomplicated bone metastases. To date, there are no data on its prophylactic coanalgesic (opioid-sparing) effect after RT in patients with complicated bone metastases compared to uncomplicated ones, which is the aim of our study. Twenty-nine American Society of Anaesthesiologists (ASA) III-IV patients, aged ≥18, treated with single-fraction 8 Gy/1 or multi-fraction 20 Gy/5 RT for painful uncomplicated bone metastases (steroid naïve patients, n = 14) or complicated ones (steroid non-naïve patients, n = 15), were examined retrospectively. All patients received parenteral dexamethasone (4 mg or 8 mg daily, 1 hour before RT, followed by the same dose for the next 4 days) along with their background and breakthrough pain opioid intake (morphine equivalents) during their 5-day in-hospital stay. Pain severity (numeric rating scale) and analgesic consumption were recorded at admission, daily during the hospital stay, and for 10 days following treatment. Binary logistic regression was used to determine predictive factors for pain flare occurrence. A higher ASA score is the only determinant positively influencing opioid consumption (P = 0.018) and pain flare as well (OR = 15.00; 95% CI: 2, 24-100, 48; P = 0.005). Lower dose 4 mg dexamethasone was revealed as a moderate analgesic agent in steroid naïve patients with no side effects, whereas in steroid non-naïve patients the predominantly higher dose 8 mg dexamethasone had minimal impact on pain flares prevention at the expense of more pronounced immunosuppression (P = 0.039). Irrespective of the supporting evidence of dexamethasone potential for prevention of RT-induced pain flare, our data failed to reveal its efficacy in the real practice world (a case mix of uncomplicated and complicated bone metastases). Further dose-effect bigger studies are needed, identifying optimal doses of dexamethasone intake and its optimal duration in high-risk patients.

Natural Language Processing of Symptoms Preceding Diagnosis and Palliative Radiotherapy for Bone Metastases

<h3>Purpose/Objective(s)</h3> In patients with bone metastases (BM), the goal of palliative radiotherapy (RT) is to ameliorate pain and other symptoms. We sought to apply natural language processing (NLP) techniques to routine clinical documentation to characterize symptoms associated with diagnosis of BM and initiation of palliative RT. We hypothesized that there may be disparities in symptom presentation for patients with BM receiving palliative RT. <h3>Materials/Methods</h3> We used International Classification of Diseases (ICD) codes along with Current Procedural Terminology (CPT) codes to create a de-identified, single tertiary-care institution cohort of patients with BM who received palliative external beam RT or stereotactic body RT between 2013 and 2021. Clinical data, clinical notes, and meta-data on clinical notes for the patient cohort were computationally extracted from an institutional electronic health record repository. We applied a previously validated clinical Text Analysis and Knowledge Extraction System (cTAKES) pipeline to extract Common Terminology Criteria for Adverse Events (CTCAE) encoded symptoms from all notes in the 30 days preceding BM diagnosis and in the 30 days preceding each course of palliative RT. Chi-squared tests were used to compare symptom distributions across groups. <h3>Results</h3> There were 1,021 patients who received 1,551 courses of palliative RT for BM. Median age at BM diagnosis was 63 years (IQR: 54-71). Median time from BM diagnosis to first course of palliative RT for BM was 2.3 months (IQR: 0.7-14.9). Most patients were male (57.5%), English-speaking (86.2%), and white (59.2%). The most common symptoms prior to BM diagnosis were pain (75.6%), nausea (44.9%), fatigue (41.6%), and palpation of a mass (38.4%). Across RT courses, the most common symptoms prior to palliative RT were pain (90.4%), nausea (67.9%), fatigue (67.6%), and constipation (54.2%). On subgroup analysis of symptoms prior to RT, there were increased NLP-derived reports of pain in clinical notes among patients who were female (94.9% vs male: 87.0%, p < 0.001), non-white (93.3% vs white: 88.8%, p = 0.007), and non-English speaking (97.0% vs English: 89.5%, p = 0.002). Compared to their respective counterparts, female (33.2% vs male: 24.6%, p < 0.001) and non-English speaking patients (36.5% vs English: 27.2%, p = 0.012) were more likely to have experienced pathologic fractures prior to RT. <h3>Conclusion</h3> Patients who were women, non-white, or non-English speaking were documented to have higher rates of pain and/or pathologic fracture prior to palliative RT. These findings may reflect disparities in patient presentation, clinical documentation, or decision-making for which patients are offered palliative RT sooner in the disease trajectory. Future research coupling NLP techniques with machine learning may be useful for predicting which patients would benefit most from earlier initiation of palliative RT.

Palliative radiotherapy of bone metastases in octogenarians: How do the oldest olds respond? Results from a tertiary cancer center with 288 treated patients

BackgroundAccompanied by the demographic change, the number of octogenarian cancer patients with bone metastases will increase in the future. Palliative radiotherapy constitutes an effective analgesic treatment; however, as pain perception and bone metabolism change with increasing age, the analgesic efficacy of radiotherapy may be altered in elderly patients. We therefore investigated the treatment outcomes of palliative radiotherapy for bone metastases in octogenarians.MethodsPatients between 80 and 89 years undergoing radiotherapy for bone metastases between 2009 and 2019 at a tertiary cancer center were analyzed for patterns-of-care, pain response and overall survival (OS). Logistic regression analyses were carried out to examine parameters associated with pain response, and Cox analyses were conducted to reveal prognostic parameters for OS.ResultsA total of 288 patients with 516 irradiated lesions were included in the analysis. The majority (n = 249, 86%) completed all courses of radiotherapy. Radiotherapy led to pain reduction in 176 patients (61%) at the end of treatment. Complete pain relief at the first follow-up was achieved in 84 patients (29%). Bisphosphonate administration was significantly associated with higher rates of pain response at the first follow-up (p < 0.05). Median OS amounted to 9 months, and 1-year, 2-year and 3-year OS were 43%, 28% and 17%. In the multivariate analysis, ECOG (p < 0.001), Mizumoto score (p < 0.01) and Spinal Instability Neoplastic Score (SINS) (p < 0.001) were independent prognosticators for OS.ConclusionPalliative radiotherapy for bone metastases constitutes a feasible and effective analgesic treatment in octogenarian patients. ECOG, Mizumoto score and SINS are prognosic variables for survival and may aid treatment decisions regarding radiotherapy fractionation in this patient group. Single-fraction radiotherapy with 8 Gy should be applied for patients with uncomplicated bone metastases and poor prognosis. Prospective trials focusing on quality of life of these very old cancer patients with bone metastases are warranted to reveal the optimal radiotherapeutic management for this vulnerable population.

Do Sustainable Palliative Single Fraction Radiotherapy Practices Proliferate or Perish 2 Years after a Knowledge Translation Campaign?

In early 2017, the Canadian Partnership Against Cancer and CancerCare Manitoba undertook a comprehensive knowledge translation (KT) campaign to improve the utilization of single fraction radiotherapy (SFRT) over multiple fraction radiotherapy (MFRT) for palliative management of bone metastases. The campaign significantly increased short-term SFRT utilization. We assess the time-dependent effects of KT-derived SFRT utilization 12–24 months removed from the KT campaign in a Provincial Cancer Program. This study identified patients receiving palliative radiotherapy for bone metastases in Manitoba in the 2018 calendar year using the provincial radiotherapy database. The proportion of patients treated with SFRT in 2018 was compared to 2017. Logistic regression analyses identified risk factors associated with MFRT receipt. In 2018, 1008 patients received palliative radiotherapy for bone metastasis, of which 63.3% received SFRT, a small overall increase in SFRT use over 2017 (59.1%). However, 41.1% of ROs demonstrated year-over-year decreases in SFRT utilization, indicative of a time-dependent loss of SFRT prescription habits derived from KT. Although SFRT use increased slightly overall in 2018, evidence of compliance fatigue was observed, suggestive of a time-perishing property of RO prescription behaviours derived from KT methodologies. Verification of the study’s findings in larger cohorts would be beneficial. These findings highlight the need for additional longitudinal KT reinforcement practices in the years following KT campaigns.

Association Between EGFR and ALK Mutation Status on Patient-Reported Symptoms After Palliative Radiation for Bone Pain in NSCLC

IntroductionAfter palliative radiotherapy for bone metastases from NSCLC, up to 30% of patients may derive no symptomatic benefit, and there are a lack of biological predictors for this. The purpose was to investigate whether EGFR and ALK genetic rearrangements were associated with greater rates of pain response to palliative radiotherapy. MethodsPatients were identified from a prospectively collected patient-reported outcomes database for all patients with lung cancer treated with conventional palliative radiotherapy for bone metastases from 2013 to 2016 in the province of British Columbia. Patients were divided on the basis of mutational status into the following: EGFR and ALK wild type (WT), EGFR mutation present (EGFR+), or ALK mutation present (ALK+). Patient-reported outcomes of global pain severity were collected before and after radiotherapy and on an ordinal scale of 0 to 4, with 0 representing no bone pain and 4 representing the maximal possible bone pain. The primary outcome was the rate of partial pain response (any improvement in score), and the secondary outcome was the rate of complete pain response (final pain score of 0). Stepwise, multivariable logistic analysis was used to compare response rates between treatment courses for different mutational statuses. ResultsThe final cohort consisted of 388 treatment courses for 329 unique patients. For the WT, EGFR+, and ALK+ groups, there were 180, 63, and nine treatment courses, respectively. There were 92 patients with no ALK and EGFR testing. The most common treatment fractionations were 8 Gy in one fraction (188 of 388) and 20 Gy in five fractions (160 of 388), and use of multifraction radiotherapy did not differ between mutation status groups (p = 0.3). Partial pain response rates were as follows: WT 63%, EGFR+ 75%, and ALK+ 78%. On multivariable analysis, rates of partial response were higher for EGFR+ (OR = 5.4, p < 0.001) and for ALK+ (OR = 12.8, p = 0.008) in comparison to WT. Complete response rates were as follows: WT 20.5%, EGFR+ 35%, and ALK+ 67%. On multivariable analysis, complete response was not significantly increased in EGFR+ compared with WT (OR = 1.6, p = 0.127). ALK+ mutation status was associated with a higher rate of complete response compared with WT (OR = 5.2, p = 0.031). ConclusionsThere was an association between EGFR+ and ALK+ tumors and increased rates of partial pain response to palliative radiotherapy.

Palliative radiation for bone metastases from hepatocellular carcinoma: practice patterns and the amount of remaining life spent receiving treatment.

Palliative radiation therapy (RT) for bone metastases (BMs) is a common practice. Wide variation exists in clinically used dose schema despite numerous studies demonstrating palliative equipoise between single and multifraction courses. We hypothesize that fraction scheme for palliating BMs for hepatocellular carcinoma (HCC) significantly affects how patients spend their remaining time. Patients with osseous HCC metastases who received RT were identified from the National Cancer Database [2004-2013]. The percentage of remaining life spent receiving radiation therapy (PRLSRT) and the number of incomplete RT courses were calculated. Kaplan-Meier analysis and Cox proportional hazards models were used to evaluate trends and predictors. A total of 1,331 patients met the inclusion criteria. Median overall survival (OS) was 3.3 months. Just 49 (3.7%) of patients received single fraction RT and 34% received >10 fractions. The mean and median PRLSRT were as follows: 1 fraction (8.9% and 3.0%), 2-5 fractions (32.9% and 24.3%), 6-10 fractions (27.2% and 15.9%), and >10 fractions (24.1% and 14.4%). Of the patients with PRLSRT >50%, 99.6% received multifraction RT. The proportion of incomplete RT courses increased as fraction size decreased from 17.6% with 4 Gy to 34% with 2 Gy. Single fraction palliative RT is vastly underutilized despite no additional palliative benefit with multifraction RT. PRLSRT significantly increased with multifraction RT. In the palliative treatment of painful BMs from HCC, single fraction treatment reduces time spent receiving radiation treatments and maximizes the number of patients who complete the prescribed treatment.

Prediction of post-radiotherapy survival for bone metastases: a comparison of the 3-variable number of risk factors model with the new Katagiri scoring system.

We investigated patient survival after palliative radiotherapy for bone metastases while comparing the prognostic accuracies of the 3-variable number of risk factors (NRF) model and the new Katagiri scoring system (Katagiri score). Overall, 485 patients who received radiotherapy for bone metastases were grouped as per the NRF model (groups I, II and III) and Katagiri score (low-, intermediate- and high-risk). Survival was compared using the log-rank or log-rank trend test. Independent prognostic factors were identified using multivariate Cox regression analyses (MCRA). MCRA and receiver operating characteristic (ROC) curves were used to compare both models’ accuracy. For the 376 evaluable patients, the overall survival (OS) rates decreased significantly in the higher-tier groups of both models (P < 0.001). All evaluated factors except ‘previous chemotherapy status’ differed significantly between groups. Both models exhibited independent predictive power (P < 0.001). Per NRF model, hazard ratios (HRs) were 1.44 (P = 0.099) and 2.944 (P < 0.001), respectively, for groups II and III, relative to group I. Per Katagiri score, HRs for intermediate- and high-risk groups were 4.02 (P < 0.001) and 7.09 (P < 0.001), respectively, relative to the low-risk group. Areas under the curve (AUC) for predicting 6-, 18- and 24-month mortality were significantly higher when using the Katagiri score (P = 0.036, 0.039 and 0.022). Both models predict survival. Prognostic accuracy of the Katagiri score is superior, especially in patients with long-term survival potential; however, in patients with short prognosis, no difference occurred between both models; simplicity and patient burden should also be considered.

Phase II Multi-Institutional Study of Low-Dose (2 Gy x 2) Palliative Radiotherapy for Symptomatic Bone Metastases From Multiple Myeloma

<h3>Purpose/Objective(s)</h3> Painful osteolytic bone lesions are common in patients with multiple myeloma (MM). Radiotherapy (RT) is effective in providing pain relief from MM bone lesions in over 80% of patients. There is no consensus as to the most effective dose or fractionation for palliation. Shorter courses of RT are not only more convenient for patients and their families, but they also have less impact on timing of systemic therapies. There is precedent for using 2 Gy x 2 for palliation of lymphomas, which have similar radiosensitivity to myeloma. The primary objective is to determine whether treatment with 2 Gy x 2 to painful myeloma bone lesions achieves patient-reported pain reduction comparable to historical controls at 4 weeks. Secondary objectives will assess QOL endpoints, use of analgesia and time to pain relief, and duration of pain relief. <h3>Materials/Methods</h3> Patients who consent to participation will complete quality of life and pain questionnaires (Brief Pain Index, EORTC QLQ-BM22, and EORTC QLQ-C30) prior to treatment and at 2,4,8 weeks and 6 months following treatment. Pain response, as defined by the international consensus on palliative RT for bone metastases, will be measured based on BPI and daily oral morphine equivalent. Reirradiation at standard dose can be considered at ≥4 weeks following initial treatment for indeterminate pain response or pain progression. Cytogenetics and International Myeloma Working Group risk stratification and response criteria are recorded, when available, but are not required for patient participation. <h3>Results</h3> This trial, supported by ILROG, has opened at 7 institutions with one more in process of opening. Prior to COVID, accrual was 1.5 patients per month. Since COVID, enrollment has been at 0.7 patients per month. A total of 18 patients have been accrued. The median age of patients accrued is 65.5 years with 7/18 female patients. Fourteen patients are Caucasian. Twelve patients have an ECOG performance score of 1-2. Thirteen patients had pain response captured at 4 weeks following RT. Of the 5 patients that did not complete questionnaires at 4 weeks post-RT, 2 expired, 1 was lost to follow-up, 1 had a missed evaluation and 1 had pain progression). The most common site of treatment was the shoulder (4/18). <h3>Conclusion</h3> This ongoing prospective trial in palliation of multiple myeloma bone lesions is feasible and able to accrue at multiple institutions and will provide valuable information as to the role of low-dose RT in this population.

The Effect of Breast Cancer Subtype on Symptom Improvement Following Palliative Radiotherapy for Bone Metastases

AimTo assess the relationship between breast cancer subtypes and patient-reported outcomes (PRO) following palliative radiotherapy for bone metastases. Materials and methodsProspectively collected PRO for all breast cancer patients treated with palliative, bone metastasis-directed radiotherapy from 2013 to 2016 in the province of British Columbia were analysed. The PRO questionnaire scored pain severity, level of function and symptom frustration at baseline and at 3–4 weeks following palliative radiotherapy using a 12-point scale. The primary outcome was the rate of overall response (any improvement in score); the secondary outcome was the rate of complete improvement in PRO (final PRO score of 0). Multivariate logistic analysis was used to compare response rates between molecular subgroup approximations of luminal A (LumA), luminal B (LumB), HER2-enriched (HER2) and triple negative (TN), as defined by grade and immunohistochemical staining. ResultsThere were 376 patients who underwent 464 courses of palliative radiation for bone metastases. Subtypes included: 243 LumA, 146 LumB, 46 HER2 and 29 TN. There were 216 multifraction radiotherapy courses (median dose 20 Gy) and 248 single-fraction radiotherapy courses (median dose 8 Gy). The overall response rate was 85% and the complete response rate was 25%. In comparison with LumA breast cancers, TN breast cancers were associated with a lower rate of overall response (69% versus 86%, P = 0.021) and a lower rate of complete response (10% versus 28.8%, P = 0.045) on multivariate analyses. ConclusionPatients with TN breast cancer have lower rates of pain, function and symptom frustration improvement following palliative radiation for bone metastases.

107: A Single Institution Retrospective Study of Palliative Radiotherapy for Bone Metastases: Comparing the First Six Months of the 2020 COVID-19 Pandemic with the Same Calendar Period During 2019

107: A Single Institution Retrospective Study of Palliative Radiotherapy for Bone Metastases: Comparing the First Six Months of the 2020 COVID-19 Pandemic with the Same Calendar Period During 2019

OC-0407 Quality of Life after Palliative Radiotherapy for Bone Metastases: Analysis of the PRESENT-cohort

OC-0407 Quality of Life after Palliative Radiotherapy for Bone Metastases: Analysis of the PRESENT-cohort

Independent Validation of a Comprehensive Machine Learning Approach Predicting Survival After Radiotherapy for Bone Metastases.

The aim of this study was to analyze the survival predictions obtained from a web platform allowing for computation of the so-called Bone Metastases Ensemble Trees for Survival (BMETS). This prediction model is based on a machine learning approach and considers 27 prognostic covariates. This was a retrospective single-institution analysis of 326 patients, managed with palliative radiotherapy for bone metastases. Deviations between model-predicted survival and observed survival were assessed. The median actuarial survival was 7.5 months. In total, 59% of patients survived for a period shorter than predicted. Twenty percent of the predictions of the median survival deviated from the observed survival by at least 6 months. Regarding actual survival <3 months (99 of 326 patients), the BMETS-predicted median survival was <3 months, i.e. correct in 67 of 99 cases (68%), whereas the model predicted a median of 4-6 months in 16 (16%) and of >6 months in another 16 cases. The model predicted survival with high accuracy in a large number of patients. Nevertheless, if the model predicts a low likelihood of 3-month survival, actual survival may be very poor (often 1 month or less). Also, in patients who died within 3 months from the start of radiotherapy, the model often predicted longer survival (16% had >6 months predicted median survival). It would, therefore, be interesting to feed the U.S. database utilized to develop the BMETS with additional poor-prognosis patients to optimize the predictions.

National Quality Measure Compliance for Palliative Bone Radiation Among Patients With Metastatic Non-Small Cell Lung Cancer.

There exists wide practice variability in palliative treatment schedules for bone metastases. In an effort to reduce variation and promote high-quality, cost-conscious care, the National Quality Forum (NQF) endorsed measure 1822 in 2012. This measure recommends the use of 30 Gy in 10 fractions, 24 Gy in 6 fractions, 20 Gy in 5 fractions, or 8 Gy in a single fraction for palliative radiation for bone metastases. We report on longitudinal compliance with this measure. Using the National Cancer Database, patients with metastatic thoracic non-small cell lung cancer diagnosed between 2004 and 2016 who received radiation therapy for bony sites of metastatic disease were identified. Treatment courses fitting 1 of the 4 recommended schedules under NQF 1822 were coded as compliant. Rates of compliance by patient, tumor, and treatment characteristics were analyzed. A total of 42,685 patients met the criteria for inclusion. Among all patients, 60.2% of treatment courses were compliant according to NQF 1822. Compliance increased over time and was highest for treatments to the extremity (69.8%), lowest for treatments to the skull or head (48.8%), and higher for academic practice (67.1%) compared with community (56.0%) or integrated network facilities (61.2%). On multivariable analysis, predictors of NQF 1822 compliance included year of diagnosis after 2011, treatment to an extremity, or treatment at an academic facility. Of noncompliant treatment courses, extended fractionation (≥11 fractions) occurred in 62.6% and was more common before 2012, in community practice, and for treatments of the skull or head. Among patients treated for metastatic non-small cell lung cancer, compliance with NQF 1822 increased over time. Although extended fractionation constituted a majority of noncompliant treatment courses, a substantial proportion also involved shorter courses.