Treatment data from 50 fractions of HDR brachytherapy of cervical cancer were reviewed, the pelvic lymph nodes were contoured, and dose-volume histogram parameters were obtained. Dose-volume histogram parameters for each contour were normalized as a percentage of the corresponding Point A dose. All nodal groups were divided into left and right sides, except the presacral nodal group.
Mean Point A doses were bilateral (Bil) 5.92 Gy ± 0.58, left (L) 5.93 ± 0.59, and right (R) 5.92 ± 0.59. Mean normalized D90 values for the various lymph node groups were as follows-obturator: Bil 20.3% ± 4.5, L 20.5% ± 4.4, and R 20.2% ± 5.2; external iliac: Bil 9.5% ± 2.9, L 10.0% ± 3.1, and R 9.5% ± 3.0; internal iliac: Bil 12.2% ± 3.5, L 12.1% ± 3.4, and R 12.9% ± 4.7; common iliac: Bil 4.3% ± 1.6, L 4.3% ± 1.6, and R 4.3% ± 1.7; and presacral: 8.7% ± 3.4. These relationships can serve as a useful tool for evaluating lymph node doses during HDR brachytherapy of cervical cancer in facilities performing two-dimensional treatment planning and those with limited resources.
回顾了50次HDR近距离放射治疗宫颈癌的治疗数据,盆腔淋巴结轮廓,并获得剂量-体积直方图参数。将每个轮廓的剂量-体积直方图参数标准化为相应的A点剂量的百分比。所有的节点组被分为左侧和右侧,除了骶前结节组。
平均A点剂量为双侧(Bil)5.92Gy±0.58,左(L)5.93±0.59和右(R)5.92±0.59。各个淋巴结组的平均归一化D90值如下:闭孔:Bil20.3%±4.5,L20.5%±4.4和R20.2%±5.2;外髂关节:Bil9.5%±2.9,L10.0%±3.1和R9.5%±3.0;内髂关节:Bil12.2%±3.5,L12.1%±3.4和R12.9%的平均D9L:1.6%±4.3%和4.7%的Bil±这些关系可以作为在执行二维治疗计划的设施和资源有限的设施中评估宫颈癌的HDR近距离放射治疗期间的淋巴结剂量的有用工具。