Department of Heavy Particles & Radiation Oncology, Taipei Veterans General Hospital, Taipei, Taiwan, R.O.C; School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C; Institute of Public Health, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C.
Department of Heavy Particles & Radiation Oncology, Taipei Veterans General Hospital, Taipei, Taiwan, R.O.C; School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, R.O.C.
Breast. 2024 Oct;77:103788. doi: 10.1016/j.breast.2024.103788. Epub 2024 Aug 12.
We introduced an adapted Lyman normal-tissue complication probability (NTCP) model, incorporating clinical risk factors and censored time-to-event data, to estimate the risk of major adverse cardiac events (MACE) following left breast cancer radiotherapy (RT).
Clinical characteristics and MACE data of 1100 women with left-side breast cancer receiving postoperative RT from 2005 to 2017 were retrospectively collected. A modified generalized Lyman NTCP model based on the individual left ventricle (LV) equivalent uniform dose (EUD), accounting for clinical risk factors and censored data, was developed using maximum likelihood estimation. Subgroup analysis was performed for low-comorbidity and high-comorbidity groups.
Over a median follow-up 7.8 years, 64 patients experienced MACE, with higher mean LV dose in affected individuals (4.1 Gy vs. 2.9 Gy). The full model accounting for clinical factors identified D = 43.3 Gy, m = 0.59, and n = 0.78 as the best-fit parameters. The threshold dose causing a 50 % probability of MACE was lower in the high-comorbidity group (D = 30 Gy) compared to the low-comorbidity group (D = 45 Gy). Predictions indicated that restricting LV EUD below 5 Gy yielded a 10-year relative MACE risk less than 1.3 and 1.5 for high-comorbidity and low-comorbidity groups, respectively.
Patients with comorbidities are more susceptible to cardiac events following breast RT. The proposed modified generalized Lyman model considers nondosimetric risk factors and addresses incomplete follow-up for late complications, offering comprehensive and individualized MACE risk estimates post-RT.
我们引入了一种改良的 Lyman 正常组织并发症概率（NTCP）模型，纳入了临床风险因素和删失时间事件数据，以估计左侧乳腺癌放疗（RT）后主要不良心脏事件（MACE）的风险。
回顾性收集了 2005 年至 2017 年间 1100 例接受术后 RT 的左侧乳腺癌女性的临床特征和 MACE 数据。采用最大似然估计法，基于个体左心室（LV）等效均匀剂量（EUD），建立了一种改良的广义 Lyman NTCP 模型，考虑了临床风险因素和删失数据。对低合并症和高合并症组进行了亚组分析。
在中位随访 7.8 年期间，64 例患者发生 MACE，受影响个体的 LV 平均剂量较高（4.1 Gy 比 2.9 Gy）。全模型考虑了临床因素，确定 D = 43.3 Gy，m = 0.59，n = 0.78 为最佳拟合参数。高合并症组的阈值剂量（D = 30 Gy）低于低合并症组（D = 45 Gy），可导致 MACE 概率为 50%。预测表明，将 LV EUD 限制在 5 Gy 以下，高合并症和低合并症组的 10 年相对 MACE 风险分别小于 1.3 和 1.5。
合并症患者在接受乳腺癌 RT 后更容易发生心脏事件。所提出的改良广义 Lyman 模型考虑了非剂量学风险因素，并解决了晚期并发症的不完全随访问题，为 RT 后提供了全面和个体化的 MACE 风险估计。
