Department of Radiation Oncology, University of Texas Medical Branch, Galveston, TX, USA.
Int J Radiat Oncol Biol Phys. 2012 May 1;83(1):235-42. doi: 10.1016/j.ijrobp.2011.06.2000. Epub 2011 Nov 19.
To define the roles of radiotherapy and chemotherapy on the risk of Grade 3+ mucositis during intensity-modulated radiation therapy (IMRT) for oropharyngeal cancer.
164 consecutive patients treated with IMRT at two institutions in nonoverlapping treatment eras were selected. All patients were treated with a dose painting approach, three dose levels, and comprehensive bilateral neck treatment under the supervision of the same radiation oncologist. Ninety-three patients received concomitant chemotherapy (cCHT) and 14 received induction chemotherapy (iCHT). Individual information of the dose received by the oral mucosa (OM) was extracted as absolute cumulative dose-volume histogram (DVH), corrected for the elapsed treatment days and reported as weekly (w) DVH. Patients were seen weekly during treatment, and peak acute toxicity equal to or greater than confluent mucositis at any point during the course of IMRT was considered the endpoint.
Overall, 129 patients (78.7%) reached the endpoint. The regions that best discriminated between patients with/without Grade 3+ mucositis were found at 10.1 Gy/w (V10.1) and 21 cc (D21), along the x-axis and y-axis of the OM-wDVH, respectively. On multivariate analysis, D21 (odds ratio [OR] = 1.016, 95% confidence interval [CI], 1.009-1.023, p < 0.001) and cCHT (OR = 4.118, 95% CI, 1.659-10.217, p = 0.002) were the only independent predictors. However, V10.1 and D21 were highly correlated (rho = 0.954, p < 0.001) and mutually interchangeable. cCHT would correspond to 88.4 cGy/w to at least 21 cc of OM.
Radiotherapy and chemotherapy act independently in determining acute mucosal toxicity; cCHT increases the risk of mucosal Grade 3 toxicity ≈4 times over radiation therapy alone, and it is equivalent to an extra ≈6.2 Gy to 21 cc of OM over a 7-week course.
定义放化疗在调强放疗（IMRT）治疗口咽癌中 3 级以上黏膜炎风险中的作用。
选择两个机构在非重叠治疗时期的 164 例连续接受 IMRT 治疗的患者。所有患者均接受剂量绘制方法、三个剂量水平和全面双侧颈部治疗，由同一位放射肿瘤学家监督。93 例患者接受同期化疗（cCHT），14 例患者接受诱导化疗（iCHT）。提取口腔黏膜（OM）接受的个体剂量信息作为绝对累积剂量-体积直方图（DVH），并根据治疗天数进行校正，以每周（w）DVH 报告。患者在治疗期间每周接受检查，在 IMRT 过程中的任何时间点出现等于或大于融合性黏膜炎的急性毒性峰值即视为终点。
总体而言，有 129 例患者（78.7%）达到终点。在 OM-wDVH 的 x 轴和 y 轴上，分别在 10.1 Gy/w（V10.1）和 21cc（D21）处发现了区分有/无 3 级以上黏膜炎患者的最佳区域。多变量分析显示，D21（比值比[OR] = 1.016，95%置信区间[CI]，1.009-1.023，p < 0.001）和 cCHT（OR = 4.118，95%CI，1.659-10.217，p = 0.002）是唯一的独立预测因素。然而，V10.1 和 D21 高度相关（rho = 0.954，p < 0.001）且可相互替换。cCHT 相当于 OM 至少 21cc 时增加 88.4cGy/w 的放射治疗。
放化疗独立作用于确定急性黏膜毒性；与单纯放疗相比，cCHT 使黏膜 3 级毒性的风险增加约 4 倍，在 7 周的治疗过程中，相当于 OM 增加约 6.2Gy 至 21cc。
