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.
Randomized trial
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.
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.