Department of Radiotherapy, University of "Piemonte Orientale", Via Solaroli 17, 28100 Novara, Italy.
Radiat Oncol. 2013 Oct 8;8:232. doi: 10.1186/1748-717X-8-232.
To analyze dosimetric parameters of patients receiving adjuvant breast radiotherapy (RT) in the prone versus supine position.
Forty-one out of 55 patients with pendulous breasts and candidates for adjuvant RT were enrolled in the study after informed consent. They underwent computed tomography (CT)-simulation in both prone and supine position. Target and non target volumes were outlined on CT images. Prescribed dose was 50 Gy delivered by two tangential photon fields followed by 10 Gy electron boost. Target coverage and dose homogeneity to clinical target volume (CTV) and planning target volume (PTV) were assessed by V95, V105 and V107 and dose to lung, heart and left anterior descending coronary artery (LAD) by V5, V10, V20, and mean and maximum dose. Data were analyzed by Student's t-test.
CTV and PTV coverage was significantly better in supine than in prone position. Lung V5, V10, and V20 were significantly lower in prone than in supine position. Heart V5, V10, V20, and LAD mean and maximum dose, in the 17 patients with left breast tumor, were lower in prone than in supine position, but without statistical significance. Based on treatment planning data and on treatment feasibility, 29/41 patients (70.7%) were treated in prone position. Acute and late toxicities of patients treated in prone and in supine position were not statistically different.
Prone position is a favorable alternative for irradiation of mammary gland in patients with pendulous breasts and in our series was adopted in 71% of the cases.
分析接受辅助乳房放疗（RT）的患者在俯卧位与仰卧位的剂量学参数。
在获得知情同意后，55 例乳房下垂且适合接受辅助 RT 的患者中有 41 例入组本研究。他们分别在俯卧位和仰卧位进行了计算机断层扫描（CT）模拟。在 CT 图像上勾画了靶区和非靶区。规定剂量为 50Gy，由两个切线光子野照射，随后进行 10Gy 电子束增强。通过 V95、V105 和 V107 评估靶区覆盖率和靶区（CTV）和计划靶区（PTV）的剂量均匀性，通过 V5、V10、V20 以及平均剂量和最大剂量评估肺、心脏和左前降支冠状动脉（LAD）的剂量。数据采用 Student's t 检验进行分析。
CTV 和 PTV 覆盖率在仰卧位显著优于俯卧位。肺 V5、V10 和 V20 在俯卧位显著低于仰卧位。在 17 例左侧乳腺癌患者中，心脏 V5、V10、V20、LAD 平均剂量和最大剂量在俯卧位显著低于仰卧位，但无统计学意义。基于治疗计划数据和治疗可行性，41 例患者中有 29 例（70.7%）采用俯卧位治疗。俯卧位和仰卧位治疗患者的急性和晚期毒性无统计学差异。
俯卧位是乳房下垂患者乳房照射的一种有利替代方法，在我们的研究中，71%的病例采用了俯卧位。
