Beriwal Sushil, Jain Sheena K, Heron Dwight E, de Andrade Regiane S, Lin Chyonghiou J, Kim Hayeon
Department of Radiation Oncology, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA.
Int J Radiat Oncol Biol Phys. 2007 Feb 1;67(2):485-9. doi: 10.1016/j.ijrobp.2006.08.067. Epub 2006 Nov 2.
To determine the dosimetric and toxicity differences between prone and supine position intensity-modulate radiotherapy in endometrial cancer patients treated with adjuvant radiotherapy.
Forty-seven consecutive endometrial cancer patients treated with adjuvant RT were analyzed. Of these, 21 were treated in prone position and 26 in the supine position. Dose-volume histograms for normal tissue structures and targets were compared between the two groups. Acute and chronic toxicity were also compared between the cohorts.
The percentage of volume receiving 10, 20, 30, 40, 45, and 50 Gy for small bowel was 89.5%, 69%, 33%, 12.2%, 5%, and 0% in the prone group and 87.5%, 62.7%, 26.4%, 8%, 4.3%, and 0% in the supine group, respectively. The difference was not statistically significant. The dose-volume histograms for bladder and rectum were also comparable, except for a slightly greater percentage of volume receiving 10 Gy (1.5%) and 20 Gy (5%) for the rectum in the prone group. Acute small bowel toxicities were Grade 1 in 7 patients and Grade 2 in 14 patients in the prone group vs. Grade 1 in 6 patients and Grade 2 in 19 patients in the supine group. Chronic toxicity was Grade 1 in 7 patients and Grade 3 in 1 patient in the prone group and Grade 1 in 5 patients in the supine group.
These preliminary results suggest that no difference exists in the dose to the normal tissue and toxicity between prone and supine intensity-modulated radiotherapy for endometrial cancer. Longer follow-up and more outcome studies are needed to determine whether any differences exist between the two approaches.
确定接受辅助放疗的子宫内膜癌患者俯卧位和仰卧位调强放疗之间的剂量学和毒性差异。
分析47例连续接受辅助放疗的子宫内膜癌患者。其中，21例采用俯卧位治疗，26例采用仰卧位治疗。比较两组正常组织结构和靶区的剂量体积直方图。同时比较两组患者的急性和慢性毒性反应。
俯卧位组小肠接受10、20、30、40、45和50 Gy剂量的体积百分比分别为89.5%、69%、33%、12.2%、5%和0%，仰卧位组分别为87.5%、62.7%、26.4%、8%、4.3%和0%。差异无统计学意义。膀胱和直肠的剂量体积直方图也具有可比性，但俯卧位组直肠接受10 Gy（1.5%）和20 Gy（5%）剂量的体积百分比略高。俯卧位组急性小肠毒性反应1级7例，2级14例；仰卧位组急性小肠毒性反应1级6例，2级19例。俯卧位组慢性毒性反应1级7例，3级1例；仰卧位组慢性毒性反应1级5例。
这些初步结果表明，子宫内膜癌俯卧位和仰卧位调强放疗对正常组织的剂量和毒性无差异。需要更长时间的随访和更多的结局研究来确定两种方法之间是否存在差异。
