目的:放射治疗(RT)结果通常根据阶段报告,患者背景,和伴随的化疗。这项研究旨在研究规定剂量对总肿瘤体积(GTV)的影响以及计算算法在头颈部(H&N)癌症的最终RT中使用RT后的随访图像对局部控制的影响。
方法:本研究纳入了在神户市医疗中心总医院接受体积调节电弧治疗的154例H&N癌症患者。将患者分为接受明确RT(70Gy照射)和未接受RT的患者。使用随访图像将患者分为响应者和非响应者组。在非响应者组中,随访图像被导入治疗计划系统,提取残留或复发区域(局部失败)的轮廓,并将其与计算机断层扫描模拟图像融合以进行治疗计划。剂量评估参数包括最大剂量,给药剂量为体积的1%,给药剂量为50%的体积,给药剂量为99%的体积(D99%),和给予GTV的最小剂量(Dmin)。在应答者和非应答者之间比较GTV的剂量。
结果:D99%在局部故障和响应者之间以及局部故障和无响应者之间表现出显着差异。Dmin显示响应者和非响应者之间以及响应者和局部失败之间的显着差异。
结论:本研究强调了在所有治疗计划中验证剂量分布的重要性,强调需要精确评估头颈部癌症中GTV的剂量。
OBJECTIVE: Radiotherapy (RT) outcomes are generally reported based on stage, patient background, and concomitant chemotherapy. This study aimed to investigate the effects of the prescribed dose to gross tumor volume (GTV) and the calculation algorithm on local control in definitive RT for head and neck (H&N) cancers using follow-up images after RT.
METHODS: This study included 154 patients with H&N cancers treated by Volumetric Modulated Arc Therapy at the Kobe City Medical Center General Hospital. Patients were classified into those receiving definitive RT (70 Gy of irradiation) and those not receiving it. Follow-up images were used to categorize the patients into the responders and non-responders groups. In the non-responders group, follow-up images were imported into the treatment planning system, and the contours of the residual or recurrent areas (local failure) were extracted and fused with computed tomography-simulated images for treatment planning. Dose evaluation parameters included maximum dose, dose administered to 1% of the volume, dose administered to 50% of the volume, dose administered to 99% of the volume (D99%), and minimum dose (Dmin) administered to the GTV. The doses to the GTV were compared between responders and non-responders.
RESULTS: D99% exhibited significant differences between local failure and responders and between local failure and non-responders. Dmin showed significant differences between responders and non-responders and between responders and local failure.
CONCLUSIONS: This study emphasizes the importance of verifying dose distribution in all slices of treatment planning, highlighting the need for precise assessment of the dose to the GTV in head and neck cancers.