前列腺癌调强放疗和三维适形放疗临床剂量学研究

目的]探讨前列腺癌调强放疗（IMRT）和三维适形放疗（3D-CRT）的剂量学差异。方法]随机选取13例局限期前列腺癌患者,采取CT定位和PHLIPSPinnacle38.0治疗计划系统对每例患者进行IMRT和3D-CRT放疗计划设计和剂量计算,分析剂量体积直方图,比较两种计划的靶区剂量分布及直肠、膀胱、股骨头等正常组织受量的差异。结果]IMRT计划中临床靶区的平均剂量（Mean）、D95、D100及CI值均高于3D-CRT计划（P〈0.01）。IMRT计划中,直肠D50、D25、V70、V45及膀胱D50、V60、V40均低于3D-CRT计划（P〈0.05）;股骨头D50显著性低于3D-CRT计划（P〈0.01）,而D5与3D-CRT计划比较无显著性差异（P〉0.05）。结论]前列腺癌放疗中,IMRT剂量分布优于3D-CRT。

A Study on Dosimetry of Intensity Modulated Radiation Therapy and Three-dimensional Conformal Radiotherapy for Prostate Cancer

Purpose] To investigate the dosimetry differences of intensity modulated radiation therapy（IMRT） and three-dimensional conformal radiotherapy（3D-CRT） for prostate cancer.Methods] Randomly selected 13 cases with locally advanced prostate cancer,planned radiation therapy program and dose calculation with IMRT and 3D-CRT for each patient by CT-taken and PHLIPS Pinnacle3 8.0 treatment planning system and dose-volume histogram were analyzed.The target dose distribution and dose difference in other normal tissues including rectum,bladder and femoral heads was analyzed.Results]The average dose in clinical target volume（Mean）,D95,D100,and CI values of IMRT were higher than those of 3D-CRT（P0.01）.D50,D25,V70,V45 in rectum and D50,V60,V40 in bladder of IMRT were lower than those of 3D-CRT（P0.05）;D50 in femoral heads was lower than that of 3D-CRT（P0.01）,while there was no difference between IMRT and 3D-CRT in D5 in femoral heads（P0.05）.Conclusions]The dose distribution of IMRT is better than that of 3D-CRT for prostate cancer.