State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou, People's Republic of China.
State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou, People's Republic of China.
Radiother Oncol. 2021 Apr;157:99-105. doi: 10.1016/j.radonc.2021.01.008. Epub 2021 Jan 21.
To develop predictive models with dosimetric and clinical variables for temporal lobe injury (TLI) in nasopharyngeal carcinoma (NPC) after intensity-modulated radiotherapy (IMRT).
Data of 8194 NPC patients who received IMRT-based treatment were retrospectively reviewed. TLI was diagnosed by magnetic resonance imaging. Dosimetric factors were selected by penalized regression and machine learning, with area under the receiver operating curve (AUC) calculated. Cox proportional hazards models containing the most predictive dosimetric factor with/without clinical variables were performed. A nomogram was generated as a visualization of Cox regression for predicting TLI-free survival.
During median follow-up of 66.8 months (interquartile range [IQR] 54.2-82.2 months), 12.1% of patients (989/8194) developed TLI. Median latency from IMRT to TLI was 36 months (IQR 28-47 months). D (dose delivered to 0.5-cm temporal-lobe volume) was the most predictive dosimetric factor (AUC: 0.799). Tolerance dose for 5% and 50% probabilities to develop TLI in 5 years were 65.06 Gy (95% confidence interval [CI]: 64.19-65.92) and 89.75 Gy (95% CI: 87.39-92.11), respectively. A nomogram comprising age, T stage, and D significantly outperformed the model with only D in predicting TLI (C-index: 0.78 vs. 0.737 in train set; 0.775 vs. 0.73 in test set; both P < 0.001). The nomogram-defined high-risk group had worse 5-year TLI-free survival.
D of 65.06 Gy was the tolerance dose of the temporal lobe. Reducing D decreased risk of TLI, especially in older patients with advanced T stage. The nomogram could predict TLI precisely and allow individualized follow-up management.
利用剂量学和临床变量为接受调强放疗（IMRT）的鼻咽癌（NPC）患者建立预测颞叶损伤（TLI）的模型。
回顾性分析了 8194 例接受基于调强放疗的 NPC 患者的数据。TLI 通过磁共振成像诊断。通过惩罚回归和机器学习选择剂量学因素，并计算受试者工作特征曲线下面积（AUC）。对包含最具预测性剂量学因素和/或临床变量的 Cox 比例风险模型进行分析。生成列线图作为 Cox 回归预测 TLI 无复发生存率的可视化。
中位随访 66.8 个月（四分位间距 [IQR]：54.2-82.2 个月）期间，12.1%（989/8194）的患者发生 TLI。从 IMRT 到 TLI 的中位潜伏期为 36 个月（IQR：28-47 个月）。剂量（0.5cm 颞叶体积所接受的剂量）是最具预测性的剂量学因素（AUC：0.799）。5 年内发生 TLI 的 5%和 50%概率的耐受剂量分别为 65.06Gy（95%置信区间 [CI]：64.19-65.92）和 89.75Gy（95% CI：87.39-92.11）。包含年龄、T 分期和 D 的列线图在预测 TLI 方面明显优于仅包含 D 的模型（训练集中的 C 指数：0.78 比 0.737；测试集中的 C 指数：0.775 比 0.73；均 P<0.001）。列线图定义的高危组 5 年 TLI 无复发生存率较差。
D 为 65.06Gy 是颞叶的耐受剂量。降低 D 可降低 TLI 的风险，尤其是在晚期 T 分期的老年患者中。该列线图可以准确预测 TLI，并允许个体化的随访管理。
