摘要目的 探讨多目标优化(MCO)算法在调强放疗计划优化中的应用.方法 随机抽取已接受治疗的10例前列腺癌和10例肺癌患者的调强治疗计划,这些计划都是基于直接子野优化算法进行优化的.在射野方向等设置条件不变前提下,改用MCO算法重新优化治疗计划.比较两种优化算法得到的剂量体积直方图参数、计划优化时间和机器跳数,并行配对t检验.结果 两种优化算法得到的调强计划均满足临床要求.与DMPO算法相比,在靶区剂量分布无差别下MCO算法使得前列腺癌计划中的直肠、膀胱及小肠受量均有不同程度降低,计划优化时间减少58％,机器跳数平均增加32％；在肺癌计划中肺、心脏和脊髓受量均有不同程度降低,计划优化时间减少59％,机器跳数平均增加11％.结论 与DMPO算法相比,MCO算法可显著降低危及器官受照剂量、缩短计划优化时间.

abstractsObjective The aim of this study was to evaluate the role of multicriteria optimization (MCO) in planning of intensity-modulated radiotherapy (IMRT).Methods Twenty IMRT patients (ten with prostate and ten with lung cancers) were randomly selected.For these patients,the treatment plans were designed with direct machine parameter optimization (DMPO).Based on these plans,new plans were designed with MCO,while keeping the setting conditions unchanged.Comparison was made between the two plans including the dose distribution,the dose volume histogram,the time of optimization and number of monitor unit (MU),but were play by pairing-t test.Results The plan designed in both optimizations satisfied all clinical requirements.For the same or better target coverage,rectum,bladder and small bowel were better with MCO compared with DMPO,MCO reduced 58％ of the time for optimization by average while MU increased 32％ by average for prostate cancer.For lung cancer,the whole lung,heart and spinal cord were better with MCO compared with DMPO,MCO reduced 59％ of the time for optimization by average while MU increased 11％ by average.Conclusions In comparison with DMPO,MCO reduces the dose of organs at risk,shorten the time of optimization.