Effectiveness of reirradiation for painful bone metastases: a systematic review and meta-analysis

The cost-effectiveness of external beam radiation therapy in bone metastases

PURPOSE OF REVIEW

Bone is the third common organ affected by metastases, and about 70% of patients with breast cancer or prostate cancer will develop bone metastases. External beam radiation therapy (EBRT) is a mainstay of treatment for patients with bone metastases. However, the effectiveness and cost-effectiveness of EBRT in patients with bone metastases have not been adequately understood. The current work aims at reviewing recent cost-effectiveness literature of EBRT on patients with bone metastases.

RECENT FINDINGS

Studies have consistently shown that EBRT is associated with significant pain relief, and existing cost-effectiveness studies have suggested that single fraction radiation therapy is more cost effective than multiple fraction radiation therapy in pain palliation. However, due to the high dependence of the data among these studies and the absence of significant amount of information, the current findings may require supports from further research in validating the results.

SUMMARY

This work sheds the light on future economic models in applying individual preference to survey questionnaires, such as, contingent valuation/conjoint choice, to carefully measure utility improvements from a treatment. In addition, research with focus on patient-centered outcome is encouraged to help clinician better understand patients' perceived outcomes of EBRT.

Single versus multiple fractions of repeat radiation for painful bone metastases: a randomised, controlled, non-inferiority trial

BACKGROUND

Although repeat radiation treatment has been shown to palliate pain in patients with bone metastases from multiple primary origin sites, data for the best possible dose fractionation schedules are lacking. We aimed to assess two dose fractionation schedules in patients with painful bone metastases needing repeat radiation therapy.

METHODS

We did a multicentre, non-blinded, randomised, controlled trial in nine countries worldwide. We enrolled patients 18 years or older who had radiologically confirmed, painful (ie, pain measured as ≥2 points using the Brief Pain Inventory) bone metastases, had received previous radiation therapy, and were taking a stable dose and schedule of pain-relieving drugs (if prescribed). Patients were randomly assigned (1:1) to receive either 8 Gy in a single fraction or 20 Gy in multiple fractions by a central computer-generated allocation sequence using dynamic minimisation to conceal assignment, stratified by previous radiation fraction schedule, response to initial radiation, and treatment centre. Patients, caregivers, and investigators were not masked to treatment allocation. The primary endpoint was overall pain response at 2 months, which was defined as the sum of complete and partial pain responses to treatment, assessed using both Brief Pain Inventory scores and changes in analgesic consumption. Analysis was done by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00080912.

FINDINGS

Between Jan 7, 2004, and May 24, 2012, we randomly assigned 425 patients to each treatment group. 19 (4%) patients in the 8 Gy group and 12 (3%) in the 20 Gy group were found to be ineligible after randomisation, and 140 (33%) and 132 (31%) patients, respectively, were not assessable at 2 months and were counted as missing data in the intention-to-treat analysis. In the intention-to-treat population, 118 (28%) patients allocated to 8 Gy treatment and 135 (32%) allocated to 20 Gy treatment had an overall pain response to treatment (p=0·21; response difference of 4·00% [upper limit of the 95% CI 9·2, less than the prespecified non-inferiority margin of 10%]). In the per-protocol population, 116 (45%) of 258 patients and 134 (51%) of 263 patients, respectively, had an overall pain response to treatment (p=0·17; response difference 6·00% [upper limit of the 95% CI 13·2, greater than the prespecified non-inferiority margin of 10%]). The most frequently reported acute radiation-related toxicities at 14 days were lack of appetite (201 [56%] of 358 assessable patients who received 8 Gy vs 229 [66%] of 349 assessable patients who received 20 Gy; p=0·011) and diarrhoea (81 [23%] of 357 vs 108 [31%] of 349; p=0·018). Pathological fractures occurred in 30 (7%) of 425 patients assigned to 8 Gy and 20 (5%) of 425 assigned to 20 Gy (odds ratio [OR] 1·54, 95% CI 0·85-2·75; p=0·15), and spinal cord or cauda equina compressions were reported in seven (2%) of 425 versus two (<1%) of 425, respectively (OR 3·54, 95% CI 0·73-17·15; p=0·094).

INTERPRETATION

In patients with painful bone metastases requiring repeat radiation therapy, treatment with 8 Gy in a single fraction seems to be non-inferior and less toxic than 20 Gy in multiple fractions; however, as findings were not robust in a per-protocol analysis, trade-offs between efficacy and toxicity might exist.

FUNDING

Canadian Cancer Society Research Institute, US National Cancer Institute, Cancer Council Australia, Royal Adelaide Hospital, Dutch Cancer Society, and Assistance Publique-Hôpitaux de Paris.

[Advances in radiation oncology for metastatic bone disease]

INTRODUCTION

Irradiation of bone metastases primarily aims at alleviating pain, preventing fracture in the short term. The higher doses and more conformal dose distribution achievable while saving healthy tissue with new irradiation techniques have induced a paradigm shift in the management of bone metastases in a growing number of clinical situations.

MATERIALS AND METHODS

A search of the English and French literature was conducted using the keywords: bone metastases, radiotherapy, interventional radiology, vertebroplasty, radiofrequency, chemoembolization. RESULTS-DISCUSSION: Stereotactic irradiation yields pain relief rates greater than 90% in Phase I/II and retrospective studies. IMRT (static, rotational, helical) and stereotactic irradiation yield local control rates of 75-90% at 2 years. Some situations previously evaluated as palliative are currently treated more aggressively with optimized radiation sometimes combined modality interventional radiology.

CONCLUSION

A recommendation can only be made for stereotactic irradiation in vertebral oligometastases or reirradiation. In the absence of a sufficient level of evidence, the increasing use of conformal irradiation techniques can only reflect the daily practice and the patient benefit while integrating economic logic care. The impact of these aggressive approaches on survival remains to be formally demonstrated by interventional prospective studies or observatories including quality of life items and minimal 2-year follow-up.

Re-irradiation for painful bone metastases - a systematic review

The purpose of this review was to determine the efficacy of re-irradiation in patients with bone metastases. A literature search was conducted in Ovid Medline, OldMedline, Embase, Embase Classic, and Cochrane Central Register of Controlled Trials using relevant subject headings and keywords such as bone metastases, radiotherapy and palliative care. The resulting articles were sorted for inclusion for palliative external beam radiation retreatment response rate data. The literature search produced 2164 references and 15 articles were included in the final selection. Complete, partial and overall response rates were calculated to be 20%, 50% and 68%, respectively. Information on treatment toxicities was scarce. The efficacy of re-irradiation is comparable to initial radiation treatment. However, aspects of re-irradiation treatment including dose fractionation, related adverse events and toxicities require further corroboration.

Prevention and Treatment of Bone Metastases in Breast Cancer

In breast cancer patients, bone is the most common site of metastases. Medical therapies are the basic therapy to prevent distant metastases and recurrence and to cure them. Radiotherapy has a primary role in pain relief, recalcification and stabilization of the bone, as well as the reduction of the risk of complications (e.g., bone fractures, spinal cord compression). Bisphosphonates, as potent inhibitors of osteoclastic-mediated bone resorption are a well-established, standard-of-care treatment option to reduce the frequency, severity and time of onset of the skeletal related events in breast cancer patients with bone metastases. Moreover bisphosphonates prevent cancer treatment-induced bone loss. Recent data shows the anti-tumor activity of bisphosphonates, in particular, in postmenopausal women and in older premenopausal women with hormone-sensitive disease treated with ovarian suppression. Pain is the most frequent symptom reported in patients with bone metastases, and its prevention and treatment must be considered at any stage of the disease. The prevention and treatment of bone metastases in breast cancer must consider an integrated multidisciplinary approach.

Painful boney metastases

Boney metastasis may lead to terrible suffering from debilitating pain. The most likely malignancies that spread to bone are prostate, breast, and lung. Painful osseous metastases are typically associated with multiple episodes of breakthrough pain which may occur with activities of daily living, weight bearing, lifting, coughing, and sneezing. Almost half of these breakthrough pain episodes are rapid in onset and short in duration and 44% of episodes are unpredictable. Treatment strategies include: analgesic approaches with "triple opioid therapy", bisphosphonates, chemotherapeutic agents, hormonal therapy, interventional and surgical approaches, steroids, radiation (external beam radiation, radiopharmaceuticals), ablative techniques (radiofrequency ablation, cryoablation), and intrathecal analgesics.

The role of palliative external beam radiation therapy in boney metastases pain management

Bone is the third most common organ affected by neoplastic metastases, and about 70% of patients with breast cancer or prostate cancer that develop metastases will have osseous involvement. As part of a multi-pronged approach to pain management in these patients, external beam radio therapy (EBRT) continues to be a mainstay of treatment for metastatic bone pain. This article reviews the role of radiation therapy in palliative management strategies for patients with bone metastases, including the clinical and cost-effectiveness of single fraction (SFRT) versus multiple fraction (MFRT) EBRT in pain relief. Studies indicate that SFRT is more cost-effective than MFRT, yet both are clinically effective in pain management. Therefore, EBRT use retains an important place among analgesia, bone modifying agents, chemotherapy, and hormone therapy in improving quality of life (QoL) and reducing morbidity from metastatic bone pain.

'Who', 'when' and 'how' in re-irradiation of recurrent painful bone metastases

Re-irradiation of painful bony metastases is increasingly performed since patients are receiving better systemic treatments and having longer life expectancy, and may also be due to the increase use of initial single fraction radiotherapy. However, randomized control trial on the efficacy of re-irradiation is lacking. A recent meta-analysis concluded with a 58% response rate for pain relief by re-irradiation of symptomatic bone metastases. In this review, the effectiveness of re-irradiation in terms of clinical and economical aspects, and clinical questions on who, when, and how to re-irradiate would be discussed. A brief review of other treatment options and comparison with re-irradiation of bone metastases would be performed.