On the other hand it was also shown that

On the other hand, it was also shown that multi-fraction long-course radiotherapy results in better re-calcification and fewer recurrences of spinal cord GW9508 within the irradiated spinal region [24,25]. In case of recurrence, Nieder et al. [10] reviewed that re-irradiation of the spinal cord to a cumulative biological equivalent dose (BED) of 130 to 135Gy2 was safe when the initial dose did not exceed 90Gy2. Therefore, for patients with spinal cord compression or who are at risk of spinal cord compression, a more protracted initial course of radiotherapy is recommended in order to avoid unsalvageable recurrence and complicated calculation during retreatment in patients with good performance status. ‘When’ to give re-irradiation? It is also generally recommended to consider re-irradiation after at least 4 weeks in patients not responding to initial radiation [26], and definitely at the time when pain recurs. When organs at risk are in-field of re-treatment portal, tissue tolerance has to be taken into consideration. However, as the time for recovery is still unknown, exact tolerance of organs at risk during retreatment is uncertain and more studies are warranted in this aspect. ‘How’ to give re-irradiation? Jeremic et al. [4] found that there was no difference in efficacy for 4, 6 or 8Gy in single fraction after an initial 4Gy single-fraction treatment. Mithal et al. [27] reported the outcomes of 105 patients with 57 out of 280 individual painful sites retreated. The pain response was 87%, in which 74% [17–23] responded with SF treatment and 91% [31–34] responded with MF treatment. The number of patients was small to draw a conclusion if MF was superior compared with SF treatment for re-irradiation. However, in cases when organs at risk are in field, careful calculation to tissue tolerance for the dose fractionation has to be taken into account. The most optimal situations and the best way to give re-irradiation to bone metastases are still unknown. The results of an ongoing study phase III study NCIC CTG SC20 [28] should be able to answer more on ‘how’ to deliver re-irradiation. The study included patients with initial radiation dose to the extremities/ribs/ pelvis with either single or multi-fractionation and only excluded patients with initial dose of 24Gy in 6 fractions, 27Gy in 8 fractions or 30Gy in 10 fractions to the spine or any part of the pelvis encompassing small or large bowel and/or the rectum.
Conclusion
Acknowledgments We thank the generous support of the Bratty Family Fund, the Michael and Karyn Goldstein Cancer Research Fund, the Joseph and Silvana Melara Cancer Research Fund, and the Ofelia Cancer Research Fund.
Background Few drugs have revolutionised the care of metastatic cancer patients as much as the bisphosphonates. These inhibitors of osteoclast function have undergone extensive clinical development over the last 20 years and have been shown to reduce hypercalcemia, bone pain, fractures, radiotherapy use, spinal cord compression and bone surgery in patients with bone metastases from a range of malignancies. They have also been shown to improve patient quality of life [1]. In addition, oncology patients will frequently receive bisphosphonates for osteoporosis, cancer treatment related bone loss and sometimes as an adjuvant therapy [2]. From an oncologist\'s standpoint these therapeutic benefits have been achieved with very few side effects when compared with most other systemic agents used in clinical practice. However, what has become evident is that as these increasingly potent bone-targeted agents are used for longer durations of time, less common side effects such as osteonecrosis of the jaw (ONJ) are presenting challenges not only to oncologists but also to the dental professionals who care for these patients.
Definition, diagnosis, incidence and risk factors for osteonecrosis of the jaw
Preventive and prophylactic measures for patients about to start and those already established on bone-targeted therapies