Department of Radiation Oncology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin Key Laboratory of Cancer Prevention and Therapy, Tianjin's Clinical Research Center for Cancer, Tianjin, China; Department of Radiation Oncology, First Medical Center of Chinese PLA General Hospital, Beijing, China; Department of Radiology, Characteristic Medical Center of Chinese People's Armed Police Force, Tianjin, China.
Department of Radiation Oncology, China-Japan Friendship Hospital, Beijing, China.
Radiother Oncol. 2023 Jul;184:109683. doi: 10.1016/j.radonc.2023.109683. Epub 2023 Apr 28.
Aim to create and validate a comprehensive nomogram capable of accurately predicting the transition from moderate-severe to normal-mild xerostomia post-radiotherapy (postRT) in patients with nasopharyngeal carcinoma (NPC).
We constructed and internally verified a prediction model using a primary cohort comprising 223 patients who were pathologically diagnosed with NPC from February 2016 to December 2019. LASSO regression model was used to identify the clinical factors and relevant variables (the pre-radiotherapy (XQ-preRT) and immediate post-radiotherapy (XQ-postRT) xerostomia questionnaire scores, as well as the mean dose (D) delivered to the parotid gland (PG), submandibular gland (SMG), sublingual gland (SLG), tubarial gland (TG), and oral cavity). Cox proportional hazards regression analysis was performed to develop the prediction model, which was presented as a nomogram. The models' performance with regard to calibration, discrimination, and clinical usefulness was evaluated. The external validation cohort comprised 78 patients.
Due to better discrimination and calibration in the training cohort, age, gender, XQ-postRT, and D of PG, SMG, and TG were included in the individualized prediction model (C-index of 0.741 (95% CI:0.717 to 0.765). Verification of the nomogram's performance in internal and external validation cohorts revealed good discrimination (C-index of 0.729 (0.692 to 0.766) and 0.736 (0.702 to 0.770), respectively) and calibration. Decision curve analysis revealed that the nomogram was clinically useful. The 12-month and 24-month moderate-severe xerostomia rate was statistically lower in the SMG-spared arm (28.4% (0.230 to 35.2) and 5.2% (0.029 to 0.093), respectively) than that in SMG-unspared arm (56.8% (0.474 to 0.672) and 12.5% (0.070 to 0.223), respectively), with an HR of 1.84 (95%CI: 1.412 to 2.397, p = 0.000). The difference in restricted mean survival time for remaining moderate-severe xerostomia between the two arms at 24 months was 5.757 months (95% CI, 3.863 to 7.651; p = 0.000).
The developed nomogram, incorporating age, gender, XQ-postRT, and D to PG, SMG, and TG, can be used for predicting recovery from moderate-severe xerostomia post-radiotherapy in NPC patients. Sparing SMG is highly important for the patient's recovery.
旨在创建并验证一个全面的列线图，以准确预测鼻咽癌（NPC）患者放疗后从中度至轻度口干（postRT）的转变。
我们使用包含 223 名经病理诊断为 NPC 的患者的主要队列构建并内部验证了预测模型，这些患者来自 2016 年 2 月至 2019 年 12 月。LASSO 回归模型用于识别临床因素和相关变量（放疗前（XQ-preRT）和放疗后即刻（XQ-postRT）口干问卷评分，以及腮腺（PG）、颌下腺（SMG）、舌下腺（SLG）、管腺（TG）和口腔的平均剂量（D））。Cox 比例风险回归分析用于开发预测模型，该模型以列线图的形式呈现。评估了模型在校准、区分和临床实用性方面的性能。外部验证队列包含 78 名患者。
由于在训练队列中具有更好的区分度和校准度，因此将年龄、性别、XQ-postRT 以及 PG、SMG 和 TG 的 D 纳入到个体化预测模型中（C 指数为 0.741（95%CI：0.717 至 0.765）。在内部和外部验证队列中验证列线图的性能显示出良好的区分度（C 指数分别为 0.729（0.692 至 0.766）和 0.736（0.702 至 0.770））和校准度。决策曲线分析表明该列线图具有临床实用性。在 SMG 保留臂中，12 个月和 24 个月的中度至重度口干发生率明显低于 SMG 未保留臂（28.4%（0.230 至 35.2）和 5.2%（0.029 至 0.093）），而在 SMG 未保留臂中，12 个月和 24 个月的中度至重度口干发生率分别为 56.8%（0.474 至 0.672）和 12.5%（0.070 至 0.223），HR 为 1.84（95%CI：1.412 至 2.397，p=0.000）。在 24 个月时，两个臂之间剩余的中度至重度口干的受限平均生存时间差异为 5.757 个月（95%CI，3.863 至 7.651；p=0.000）。
该列线图纳入了年龄、性别、XQ-postRT 和 PG、SMG 和 TG 的 D，可以用于预测 NPC 患者放疗后从中度至重度口干的恢复情况。保留 SMG 对患者的恢复非常重要。
