Alberts A S, Smit B J, Louw W K, van Rensburg A J, van Beek A, Kritzinger V, Nel J S
Department of Radiation Oncology, H.F. Verwoerd Hospital and University of Pretoria, Arcadia, South Africa.
Radiother Oncol. 1997 May;43(2):175-9. doi: 10.1016/s0167-8140(97)01912-9.
The optimal dose of samarium-153-EDTMP (153Sm-EDTMP) for effective palliation of painful metastases to bone is under investigation. It is not known whether increased doses of 153Sm EDTMP will lead to better and longer pain and tumour control and survival. Multiple dose efficacy and toxicity is of importance as most Patients will require prolonged support for pain.
Twenty-eight (28) patients were treated with 0.75 mCi/kg, 35 patients with 1.5 mCi/kg and 19 patients with 3 mCi/kg in three sequential Phase I-II trials. Multiple doses were given to patients on the 0.75 mCi/kg and 1.5 mCi/kg dose levels.
At all dose levels adequate pain control was achieved in 78-95% of patients. The duration of pain control was 40-56 days with the best results in the 1.5 mCi/kg group (56 days). There is no evidence that increasing dose leads to better and longer pain control, tumour response and survival, but toxicity is increased. Multiple doses can be given with acceptable toxicity and pain control, however, only 38% of patients will qualify for multiple treatments.
153Sm-EDTMP provides adequate and safe palliation but multiple doses can only be given in 38% of patients. There is not a clear dose-response relationship. The length of pain control is satisfactory but not ideal and hospitalisation for 4 days every 6-8 weeks is a disadvantage. Further research is required to combine 153Sm-EDTMP with cytostatics and to administer it on an out patient basis.
用于有效缓解骨转移疼痛的钐-153-乙二胺四甲撑膦酸（153Sm-EDTMP）的最佳剂量正在研究中。尚不清楚增加153Sm EDTMP的剂量是否会带来更好、更持久的疼痛及肿瘤控制和生存效果。由于大多数患者需要长期的疼痛支持，多次给药的疗效和毒性至关重要。
在三项连续的I-II期试验中，28例患者接受了0.75毫居里/千克的治疗，35例患者接受了1.5毫居里/千克的治疗，19例患者接受了3毫居里/千克的治疗。0.75毫居里/千克和1.5毫居里/千克剂量水平的患者接受了多次给药。
在所有剂量水平下，78%-95%的患者实现了充分的疼痛控制。疼痛控制的持续时间为40-56天，1.5毫居里/千克组效果最佳（56天）。没有证据表明增加剂量会带来更好、更持久的疼痛控制、肿瘤反应和生存效果，但毒性会增加。多次给药的毒性和疼痛控制可接受，然而，只有38%的患者符合多次治疗的条件。
153Sm-EDTMP提供了充分且安全的缓解，但只有38%的患者可以接受多次给药。不存在明确的剂量反应关系。疼痛控制的时长令人满意但并不理想，每6-8周住院4天是一个不利因素。需要进一步研究将153Sm-EDTMP与细胞抑制剂联合使用，并在门诊给药。
