Griem Katherine L, Fetherston Pam, Kuznetsova Marina, Foster Gregory S, Shott Susan, Chu James
Department of Radiation Oncology, Rush-Presbyterian-St. Luke's Medical Center, Chicago, IL 60612, USA.
Int J Radiat Oncol Biol Phys. 2003 Nov 1;57(3):891-9. doi: 10.1016/s0360-3016(03)00723-5.
To compare the adequacy of target coverage, dose homogeneity, and volume of normal tissue irradiated in treatment of the intact breast in the supine and prone position.
Fifteen patients with early breast cancer who presented for treatment to the intact breast after excisional biopsy were studied. A specially designed device was used for the prone setup to displace the contralateral breast away from the tangential field borders. Treatment planning computed tomography was performed for each patient in both the supine and prone positions. Dosimetric data were obtained in both positions and isodose distributions were calculated for each patient in both positions.
The volume of breast receiving greater than 5% of the prescribed dose was significantly less in the prone position. Medial wedges were either not used or their angles were reduced for all patients in the prone position compared with the supine position. The average volume of lung receiving >10 Gy and >20 Gy was significantly less in the prone positions. The volume of heart irradiated at critical dose levels did not vary consistently in the prone and supine positions. The integral dose delivered to the contralateral breast was not significantly different.
Treatment of the intact breast in the prone position may result in improved dose homogeneity within the target volume as well as sparing of normal lung compared with treatment in the conventional supine position.
比较仰卧位和俯卧位治疗完整乳腺时靶区覆盖的充分性、剂量均匀性以及正常组织受照射体积。
对15例在切除活检后前来接受完整乳腺治疗的早期乳腺癌患者进行研究。使用专门设计的装置进行俯卧位设置，以使对侧乳腺远离切线野边界。对每位患者在仰卧位和俯卧位均进行治疗计划计算机断层扫描。在两个体位均获取剂量学数据，并计算每位患者在两个体位的等剂量分布。
俯卧位时接受大于规定剂量5%的乳腺体积显著更小。与仰卧位相比，俯卧位所有患者内侧楔形板要么未使用，要么其角度减小。俯卧位时接受>10 Gy和>20 Gy照射的肺平均体积显著更小。在俯卧位和仰卧位，关键剂量水平照射的心脏体积变化不一致。对侧乳腺的积分剂量无显著差异。
与传统仰卧位治疗相比，俯卧位治疗完整乳腺可能会使靶区内剂量均匀性得到改善，同时减少正常肺组织受照。
