张口固定联合唇剂量限制对鼻咽容积调强放疗患者口腔剂量及毒性影响:基于103例鼻咽癌分析

Comparison of Oral Dose and Toxicity Undergoing Volumetric Modulated Arc Therapy with or Without Mouth-opening Fixation Combined with Lips Dose Constraining: Based on 103 Patients of Nasopharyngeal Carcinoma

[目的]探讨张口固定联合唇剂量限制对减少鼻咽容积调强放疗患者口腔剂量及黏膜毒性的影响。[方法]回顾性分析103例鼻咽癌患者资料(实验组52例,对照组51例),对照组采用常规热塑膜固定体位,实验组加用口咬器固定及限制唇平均剂量小于25 Gy。收集两组患者口腔、舌根、舌体、颊黏膜、咬肌及颌下腺的体积剂量学参数,以及两组患者放疗开始后出现Ⅱ级及以上口腔黏膜损伤发生的时间。[结果]实验组颊黏膜、口腔、舌根及咬肌的平均剂量均低于对照组(30.45 Gy vs 34.09 Gy,34.72 Gy vs 37.58 Gy,40.76 Gy vs 42.90 Gy,37.63 Gy vs 38.71 Gy,P均<0.05)。实验组及对照组患者发生Ⅱ级及以上急性口腔黏膜炎的比例分别为48.08%和82.35%(P<0.001),平均发生时间为放疗开始后的(24.44±8.90) d和(18.07±9.43) d(P=0.01)。[结论]张口固定联合唇剂量限制能降低鼻咽癌容积调强放疗患者Ⅱ级及以上急性口腔黏膜损伤的发生比例,并推迟其发生时间。

[Objective] To investigate the mouth-opening fixation combined with lips dose constraining in reducing oral dose and mucositis for nasopharyngeal carcinoma patients receiving volumetric intensity modulated arc therapy. [Methods] One hundred and three cases with of nasopharyngeal carcinoma were retrospectively enrolled in the experimental group(n=52) and control group(n=51), respectively.The control group patients were fixed with thermoplastic while the experimental group patients were fixed with an additional oral bite device and adopted mean dose constraining of lips to less than 25 Gy in planning design. The volumetric dosimetry parameters of the oral cavity, tongue base, tongue body,buccal mucosa, masseter muscle and submandibular gland of the two groups of patients were collected,and the occurrence time of grade Ⅱ or above acute oral mucositis in the two groups after the start of radiotherapy were recorded. [Results] The mean dose of the buccal mucosa, oral cavity, tongue root and masseter in the experimental group were lower than those of the control group(30.45 Gy vs 34.09 Gy,34.72 Gy vs 37.58 Gy, 40.76 Gy vs 42.90 Gy, 37.63 Gy vs 38.71 Gy, all P<0.05). The proportion of patients in the experimental and control group presenting acute oral mucositis of grade Ⅱ and above were 48.08% and 82.35%(P<0.001), the average occurrence time was(24.44±8.90) d and(18.07±9.43) d after the start of radiotherapy(P=0.01). [Conclusion] Mouth-opening fixation combined with lip dose constraining can reduce the incidence of grade Ⅱ and above acute oral mucositis in patients with nasopharyngeal carcinoma undergoing volumetric modulated arc therapy, and delay its occurrence.