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.

Influence of Dexamethasone Premedication on Acute Lung Toxicity in Lung SBRT

Introduction

The cooperative group experience of thoracic sterotactic body radiation therapy (SBRT) in medically inoperable patients with early stage non-small cell lung cancer (NSCLC) historically utilized corticosteroid premedication. Patterns of care have been mixed as to whether premedication adds benefit in terms of improved lung toxicity and treatment tolerance.

Methods

Patients treated for NSCLC from 2014 to 2017 with definitive thoracic SBRT (BED₁₀≥100) at a single institution, in a prospectively collected database were evaluated. Pretreatment clinicopathologic characteristics, including Eastern Cooperative Oncology Group (ECOG) performance status, PFT parameters of FEV1, and diffusing capacity for carbon monoxide (DLCO) were collected. Treatment and dosimetric characteristics were collected, and patients were scored as to whether dexamethasone was prescribed and utilized with each fraction. Toxicity was graded on multiple domains including lung as during and 30 days after completion of treatment using Common Terminology Criteria for Adverse Events Version 4. Univariate analysis was performed with Fisher’s exact test for categorical variables and two-tailed Student’s t-test for continuous variables. Multivariate analysis was performed with Cox proportional hazards model to adjust for age, pretreatment DLCO, ECOG, tumor size, central versus peripheral location, and biological effective dose.

Results

A total of 86 patients treated with thoracic SBRT with 54–60 Gy in 3–8 fractions met inclusion criteria, with the majority (70%) receiving 5 fractions. Of these patients, 45 (52%) received 4 mg dexamethasone premedication prior to each fraction of SBRT and 41 (48%) were treated without dexamethasone premedication. Overall acute lung toxicity was low in both groups. Between the two groups of patients, 5/45 (11%) developed grade 2 or higher lung toxicity including hospital admission in the dexamethasone premedication arm vs. 2/41 (5%) without premedication (p = 0.4370, Fisher’s exact test). Freedom from acute SBRT lung toxicity was no different between dexamethasone premedication arm and no premedication (Log rank, p = 0.45). On multivariate Cox proportional hazard modeling adjusting for age, ECOG, tumor size, central vs. peripheral location, pretreatment DLCO, and BED, there was no difference in freedom from acute lung toxicity without dexamethasone premedication (HR: 0.305; 95% CI: 0.033, 2.792; p = 0.293).

Conclusions

In this retrospective analysis, pretreatment steroid prophylaxis with dexamethasone confers a similar acute toxicity profile and no added clinical benefit to treatment without pretreatment steroid prophylaxis.

Prophylactic corticosteroid to prevent pain flare in bone metastases treated by radiotherapy

Background

The aim of this study was to evaluate the effectiveness of prophylactic corticosteroids to prevent pain flare (PF) in bone metastases treated with radiotherapy performing a meta-analysis of randomized clinical trials (RCT).

Materials and methods

RCTs were identified on Medline, Embase, the Cochrane Library, and the proceedings of annual meetings through June 2020. We followed the PRISMA and MOOSE guidelines. A meta-analysis was performed to assess if corticosteroids reduce the PF, pain progression, and the mean of days with PF compared with the placebo. A p-value < 0.05 was considered significant.

Results

Three RCTs with a total of 713 patients treated were included. The corticosteroids reduced the occurrence of early PF 20.5% (51/248) versus 32% (80/250) placebo, OR = 0.55 (95% CI: 0.36-0.82, p = 0.002). The mean days of PF were reduced to 1.6 days (95% CI: 1.3-1.9, p = 0.0001). Prophylactic corticosteroids had more patients with no PF and no pain progression, OR = 1.63 (95% CI: 1.14-2.32, p = 0.007). No significant corticosteroids effect was observed for pain progression (p = ns) and late PF occurrence (p = ns).

Conclusion

Prophylactic corticosteroids reduced the incidence of early PF, the days with PF, resulting in a superior rate of patients with no PF and no pain progression, but with no significant benefit for reducing pain progression or late PF occurrence.

Effect of an electronic quality checklist on prescription patterns of prophylactic antiemetic and pain flare medications in the context of palliative radiotherapy for bone metastases

PURPOSE

International guidelines are available to guide prescription of antiemetic and pain flare medications in patients receiving palliative radiotherapy for bone metastases, but prescription rates are quite variable. We hypothesized that a simple electronic quality checklist could increase the evidence-based use of these medications.

MATERIALS AND METHODS

We implemented an electronic quality checklist item in our center for all patients treated with palliative radiotherapy for lumbar spine bone metastases. We retrospectively reviewed patients in the 6-month pre- and post-intervention. Patients were stratified according to if they were treated within a dedicated rapid palliative (RPAL) radiotherapy program or not. Chi-square tests were used to compare rates of antiemetic and pain flare medications pre- and post-intervention and RPAL vs not.

RESULTS

A total of 375 patients were identified with 42 (11.2%) treated in dedicated RPAL program. The proportion of patients treated with prophylactic antiemetic and pain flare medications pre-intervention (n = 226) and post-intervention (n = 149) was respectively 34.1% vs 59.1% (p < 0.001) and 26.1% vs 43.0% (p = 0.01). Observed differences for antiemetic prescription rates were greater for patients who were not treated within a dedicated palliative radiotherapy program, but this was not the case for pain flare medications.

CONCLUSIONS

Our data shows that a simple quality checklist item can have a significant effect on the evidence-based use of prophylactic antiemetic and pain flare medications in patients treated with palliative radiotherapy for bone metastases. We believe such strategies should be routinely included in other clinical pathways to improve the use of symptom control medications.