1424P - Comparison of 8GY Single Fraction Radiotherapy Versus 20GY in Five Fractions or 30GY in 10 Fractions for the Treatment of Metastatic Bone Pain

Abstract

ABSTRACT Introduction In 1974 the Radiation Therapy Oncology Group (RTOG) initiated a randomized clinical trial comparing various dose-fractionation schedules in the palliation of cancer metastatic to bone. The trial was closed in February of 1980 and results have been published in 1982, with the conclusion that: “low-dose short schedules are as effective as more aggressive protracted programs. Since that time, different radiotherapy schedules had been employed for palliation of bone metastasis: 40 Gy in 20 fractions, 30 Gy in 10 fractions and single fractions of 8 Gy, 6 Gy or 4 Gy. Several randomized prospective trials and meta-analyses have been reported showing the same results in pain relief when comparing single doses vs protracted treatments. Objectives The aim of this study was to compare the most common fractionation used in oncology to treat bone metastases which are 8Gy single fraction, 20Gy in five fractions and 30Gy in 10 fractions. Method A total dose of 120 patients who is known to have stage VI cancer with bone metastasis at King Hussein Medical Center between January 2007 and December 2009, were allocated to receive either 8Gy single fraction, 20Gy in five fractions or 30Gy in 10 fractions for the treatment of their pain. Patient recorded pain severity and analgesic requirements on questionnaire which was filled by the main investigator before treatment, at 2 weeks and at 1,2,3,4,5,6,8,10, and 12 months after radiotherapy. Pain relief was the primary endpoint of treatment benefit. Results There was no difference in the time to first improvement in pain, time to complete pain relief or in time to first increase in pain at any time up to 12 months after randomization, nor in the class of analgesic used. Retreatment was twice as common after 8Gy than after multifraction radiotherapy, although retreatment for residual or recurrent pain did not reflect a difference between the three groups in the probability of pain relief. Conclusion A single fraction of 8 Gy when used for the treatment of bone metastasis is as safe and effective as a multifraction regimen for the palliation of metastatic bone pain for at least 12 months. This may make it suitable alternative to the multifraction radiotherapy regimens. Keywords: Bone metastases; Radiotherapy; Pain relief; Palliation Disclosure All authors have declared no conflicts of interest.