20 Gy in five fractions versus 8 Gy in one fraction in palliative radiotherapy of bone metastases : a multicenter randomized study

ntroduction. Bone is the most common site of cancer dissemination and 70% of patients with bone lesions present with pain requiring therapy. Radiotherapy plays a major role in the treatment of painful bone metastases, but optimal dose and fractionation regime remain debatable. Material and methods. To address this issue a randomized trial comparing a single dose of 8 Gy vs. 20 Gy in 5 fractions was performed and enrolled 115 patients with 146 metastatic lesions. Pain relief was assessed longitudinally based on a pain questionnaire, in which patients were supposed to record their pain intensity using a 4-point scale (none, mild, moderate, severe), as well as doses and types of analgesic drugs taken. Questionnaires were collected prior to treatment, 2, 4 and 8 weeks after treatment completion and every 4 weeks thereafter Results. Complete pain relief was achieved in 23 patients (36%) treated with one fraction of 8 Gy and in 24 patients (39%) who received 20 Gy in 5 fractions (p=0.96). Remarkable pain relief after one fraction and 5 fractions was achieved in 21 patients (33%) and 18 patients (29%), respectively (p=0.89) and moderate pain relief in 9 patients (14%) and 10 patients (16%), respectively (p=0.94). There was also no difference between the two treatment regimes according to duration of pain relief (medians of 8 and 10 months, respectively). Conclusions. Single fraction of 8 Gy is equally effective to a fractionated schedule in the treatment of painful bone metastases, and should be recommended as standard care in the majority of patients.