Hoskin, P., Rojas, A., Fidarova, E., Jalali, R., Mena Merino, A., Poitevin, A., . . . Jeremic, B. (2015). IAEA randomised trial of optimal single dose radiotherapy in the treatment of painful bone metastases. Radiotherapy and Oncology, 116, 10–14. 

To determine the optimal single-dose radiotherapy schedule for pain related to bone metastases

Patients were randomly assigned to receive a single dose of 8 Gy, a single dose of 4 Gy, or 12 Gy in four fractions given over two consecutive days. Additional treatment with 8 Gy was given if moderate or severe pain persisted. Analgesic use was documented at baseline and at each follow-up. Patients were assessed at baseline and at four, eight, 12, 24, and 52 weeks.

• N = 545 at week 4  
• MEDIAN AGE = 57 years (range = 25–88 years)
• MALES: Not provided, FEMALES: Not provided
• KEY DISEASE CHARACTERISTICS: Multiple tumor types; metastasis sites were spine, pelvis, hip, femur, humerus, and other sites
• OTHER KEY SAMPLE CHARACTERISTICS: About 21% of patients were not receiving any analgesics at baseline, and 34% were receiving strong opioids.

• SITE: Multi-site  
• SETTING TYPE: Outpatient  
• LOCATION: International

• PHASE OF CARE: Late effects and survivorship
• APPLICATIONS: Palliative care

Randomized trial

• 10 cm Visual Analog Scale (VAS) for pain
• Four-point scale for pain (0 = none, and 4 = severe)
• Complete response (CR) was defined as no pain and a score of 0 on the VAS. Partial response (PR) was defined as a reduction of one point on the four-point scale or a VAS reduction of at least 10 mm.

Across all follow-up time points, the proportion of those with CR and PR was higher with radiotherapy at 8 Gy although the difference between the groups was only significant at eight weeks. More treatments were needed with 4 Gy radiotherapy (p = 0.01). The response rate with 8 Gy was 70%–80% at four weeks compared to 82% with 4 Gy.

A single dose of 8 Gy radiotherapy was associated with higher CR rates, and a dosage of 4 Gy was effective in a substantial number of patients.

• Risk of bias (no blinding)
• Measurement/methods not well described 
• Other limitations/explanation: How pain data was collected was not stated. No information was provided on any changes in analgesics or the use of bone modifying agents.

Both single-dose 4 Gy and 8 Gy radiotherapy were effective in reducing pain in the majority of patients. An 8 Gy dosing was beneficial in a higher proportion of patients, and fewer patients at this dose required additional treatment. Individual patient variables need to be considered in determining dosages based on tolerance and concerns about toxicity.