RESUMO
To evaluate prospectively the outcome in terms of palliation, prognostic factors for pain relief and side effects of the local-field reirradiation for painful bone metastases. Between April 2005 and Feb. 2006, 32 cancer patients in Assiut University Hospital, Oncology Department were reirradiated for painful bone metastases. All patients were previously treated with the same regimen 30 Gy/10 Fr/2 wk for the same bone metastases. Reirradiation doses were 10 Gy in 5 fractions in one week to vertebra lesions related to the spinal cord [from C1 to L1] [regimen A] and 20 Gy in 10 fractions in two weeks to other lesions [regimen B]. For regimen A, accumulated biological effective dose [BED] for acute and late effects = 42.5 Gy10 and 43.67 Gy3 respectively. For regimen B, accumulated BED for acute and late effects = 52.5 Gy10 and 53.67 Gy3 respectively. At initial treatment of palliative irradiation: 7 [21.88%] had complete pain relief [CR], 22 [68.65%] had partial relief [PR] and 3 [9.38%] had no response. After reirradiation: 5 patients [15.6%] had CR and 12 [37.5%] had PR. The remaining 15 patients [46.9%] did not benefit from retreatment. 7 patients in first palliative irradiation in CR had obtained either CR in [5] and PR [2]. The response rate of patients with CR at initial treatment was 100% [7/7], and that of patients with previous PR was 45.4% [10/22, p<0.01]. The median duration of pain relief was five months. The median duration of response was 8.5 months and four months with initial CR and initial PR, respectively, [p<0.01]. The factors associated with pain relief were the status of bone metastases [solitary bone metastases], PS [KPS >/= 70%], and duration after initial treatment [>4 months]. All patients tolerated retreatment very well. During treatment and follow-up, no serious side effects were seen. The presented study shows usefulness of the re-radiotherapy with the prescribed doses as a safe and effective method of palliative treatment in cases of painful bone metastases