Department of Radiotherapy, Taizhou Central Hospital (Taizhou University Hospital), No.999 Donghai Road, Taizhou, 318000, Zhejiang, People's Republic of China.
World J Surg Oncol. 2023 Feb 23;21(1):59. doi: 10.1186/s12957-023-02936-8.
The purpose of this study was to explore the influence of individual patient factors, such as volume of the planning target volume (PTV) (V), cardiothoracic ratio (CTR), central lung distance (CLD), and maximal heart distance (MHD), on the design of treatment plans in terms of target dose coverage, integral dose, and dose to organs at risk (OAR) in early breast cancer.
Ninety-six patients were selected for this study. Radiation doses of 50 Gy and a simultaneous dose of 60 Gy in 25 fractions were administered to the whole breast and tumor bed, respectively. The intensity modulation plan (IMRT) of each patient uses both physical parameters and an equivalent uniform dose (EUD) to optimize the target function. Univariate and multivariate linear regression were used to analyze the relationship between predictive impact factors and OAR percent dose volume, conformity index (CI), and homogeneity index (HI).
The average CI and HI values of the left breast cancer plan were 0.595 ± 0.071 (0.3-0.72) and 1.095 ± 0.023 (1.06-1.18), respectively. The CTR (B = 0.21, P = 0.045), V (B = 0.63, P = 0.000), volume of the lung (V) (B = - 0.29, P = 0.005), and MHD (B = 0.22, P = 0.041) were identified as factors influencing the CI index of the left breast cancer intensity modulation plan. V (B = 1.087, P = 0.022) was identified as the influencing factor of the HI index of the left breast cancer intensity modulation plan. volume of the heart (V) (B = - 0.43, P = 0.001) and CLD (B = 0.28, P = 0.008) were influencing factors of the volume of lung (V) of the lung. The prediction formulas for left-sided breast cancer are noted as follows: CI = 0.459 + 0.19CTR-0.16CLD, V10 = 35.5-0.02V; and V20 = 21.48 + 2.8CLD-0.018V.
CTR, CLD, and MHD can predict the rationality of the parameters of the left breast cancer IMRT. The calculation formula generated based on this information can help the physicist choose the optimal radiation field setting method and improve the quality of the treatment plan.
本研究旨在探讨个体患者因素（如计划靶区（PTV）体积（V）、心胸比（CTR）、中央肺距离（CLD）和最大心脏距离（MHD））对早期乳腺癌治疗计划靶区剂量覆盖、整体剂量和危及器官（OAR）剂量的影响。
本研究共纳入 96 例患者。50Gy 的全乳腺照射和 60Gy 的肿瘤床同步照射，分割 25 次。每位患者的调强计划（IMRT）都使用物理参数和等效均匀剂量（EUD）来优化靶区函数。采用单因素和多因素线性回归分析预测影响因素与 OAR 百分剂量体积、适形指数（CI）和均匀性指数（HI）的关系。
左侧乳腺癌计划的平均 CI 和 HI 值分别为 0.595±0.071（0.3-0.72）和 1.095±0.023（1.06-1.18）。CTR（B=0.21，P=0.045）、V（B=0.63，P=0.000）、肺体积（V）（B= -0.29，P=0.005）和 MHD（B=0.22，P=0.041）被确定为影响左侧乳腺癌调强计划 CI 指数的因素。V（B=1.087，P=0.022）被确定为影响左侧乳腺癌调强计划 HI 指数的因素。心脏体积（V）（B= -0.43，P=0.001）和 CLD（B=0.28，P=0.008）是肺体积（V）的影响因素。左侧乳腺癌的预测公式如下：CI=0.459+0.19CTR-0.16CLD，V10=35.5-0.02V；V20=21.48+2.8CLD-0.018V。
CTR、CLD 和 MHD 可预测左侧乳腺癌 IMRT 参数的合理性。基于这些信息生成的计算公式可以帮助物理学家选择最佳的辐射场设置方法，提高治疗计划的质量。
