肿瘤控制概率模型研究外照射分次剂量与治疗的关系

目的：研究在给定治疗剂量和治疗时间的情况下，使用不等分次剂量（UEFD）治疗方案是否能治疗效果。方法：参考细胞存活率的计算公式，推导出分次治疗时的肿瘤控制概率（TCP）的计算模型，然后在假设的全序程或1周1内分次剂量以等比数列，等差数列递增或递减等4种分次剂量方案及肿瘤生物学参数的情况下，计算给定总治疗剂量D所能获得的TCP值，能作TCP与D的关系曲线及TCD50与等比或等差之间的关系曲。结果：上述4种UEFD方案所得到的TCP－D曲线治疗好于递增分次剂量治疗，但分次剂量间变化幅度小时两者间的差异不明显。结论：从理论上讲，在给定治疗剂量及治疗的情况下用UEFD治疗能获比EFD治疗更好的结果。

Research on relationship between dose per fraction and therapeutic effect in fractionated radiotherapy with a tumor control probability model

Objective\ To study whether the effect can be improved by using unequal dose per fraction in fractionated radiotherapy with the given overall treatment dose and time. Methods\ Referring to the calculating formula of cell surviving probability,a new tumor control probability(TCP) calculating model following the fractionated radiotherapy has been set up.Then with four assumed fractionated dose protocols(fractionated dose increase or decrease in a week or in the whole treatment time),the TCP value will be calculated with the calculation model to get the relationship curves of some interested variables. Results\ The calculation results show that the four assumed unequal fractionated dose(UEFD) protocols were better than the conventional equal fractionated dose(EFD)protocol.The more uneven fractionated dose distribution was the better TCP results would be. Conclusion\ Given the overall treatment dose and time,treatment with UFED protocols can get better therapeutic effect than treatment with EFD protocol theoretically.