Mesina C F, Sharma R, Rissman L S, Geering L, He T, Forman J D
Department of Radiation Oncology, Wayne State University, Detroit, MI.
Int J Radiat Oncol Biol Phys. 1994 Sep 30;30(2):427-30. doi: 10.1016/0360-3016(94)90024-8.
A comparative study of a standard four-field boost technique and a customized nonaxial external beam technique for the treatment of adenocarcinoma of the prostate was performed to quantify rectal and bladder sparing.
Sixteen patients with localized carcinoma of the prostate who underwent simulation and treatment planning computed tomography formed the basis of this study. The prostate, seminal vesicles, lymph node, pelvic bones, rectum, bladder, and skin volumes were contoured from the CT slices to the three-dimensional treatment planning system. Each patient was planned for both standard four-field and nonaxial techniques to a boost treatment dose of 24 Gy to the prostate. Isodose plans were chosen on the basis of adequate tumor coverage and normal tissue sparing.
The volumes of the prostate, rectum, and bladder ranged from 46-148 cc, 25-196 cc, and 50-378 cc, respectively. Data analysis demonstrated a statistically significant reduction (p < 0.01) in normal tissue irradiation with the nonaxial external beam technique at dose levels of 15 and 20 Gy.
The nonaxial four-field external beam technique appears to be superior to the standard four-field approach in reducing the volume of high dose irradiation to the adjacent rectum and bladder.
对标准四野加量技术和定制非轴向外照射技术治疗前列腺腺癌进行比较研究，以量化直肠和膀胱的受量。
16例接受模拟和治疗计划CT扫描的局限性前列腺癌患者构成了本研究的基础。从CT图像上勾画出前列腺、精囊、淋巴结、骨盆、直肠、膀胱和皮肤的体积，并输入三维治疗计划系统。每位患者均采用标准四野技术和非轴向技术进行计划，前列腺加量治疗剂量为24 Gy。根据肿瘤充分覆盖和正常组织受量情况选择等剂量计划。
前列腺、直肠和膀胱的体积分别为46 - 148 cc、25 - 196 cc和50 - 378 cc。数据分析表明，在15 Gy和20 Gy剂量水平下，非轴向外照射技术可使正常组织受量显著减少（p < 0.01）。
在减少对相邻直肠和膀胱的高剂量照射体积方面，非轴向四野外照射技术似乎优于标准四野技术。
