Customized double-shell immobilization device combined with VMAT radiation treatment of basosquamous cell carcinoma of the scalp
Customized double-shell immobilization device combined with VMAT radiation treatment of basosquamous cell carcinoma of the scalp
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DOI：
10.1002/acm2.12536
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发表时间：
2019-02-01
影响因子：
2.1
通讯作者：
Saoudi, Abdelhamid
中科院分区：
文献类型：
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作者：
Mail, Noor;Al-Ghamdi, Suliman M.;Saoudi, Abdelhamid
头皮/颅骨浅表受累的恶性肿瘤对放射治疗计划提出了技术挑战，例如用处方剂量实现皮肤覆盖，并具有理想的一致性、均匀性和较低的脑剂量。我们报告一个放射治疗技术的病人诊断为弥漫性基底鳞状细胞癌的头皮和邻近的头骨。这项研究提出了计划的质量参数，病人的剂量测定，和病人的结果。患者接受了容量调制弧治疗（VMAT）和双壳团注全头装置（DSBFD）治疗，旨在固定患者并改善皮肤覆盖。使用Eclipse治疗计划系统生成VMAT计划，处方剂量为60戈伊，分30次。分析治疗计划以确定符合性指数（CI）、均匀性指数（HI）、靶区覆盖率和危及器官剂量（OAR）。皮肤剂量使用光激发光（OSL）剂量计测量。在放疗过程中和放疗后，由放射肿瘤学家进行临床随访。关于计划靶体积（PTV）覆盖率，V-95为99%。测量和计算的皮肤剂量在处方剂量的100-108%范围内。平均脑PTV剂量为711 cGy。CI和HI分别为1.09和1.08。在整个治疗过程中，患者的平均定位精度在2 mm以内。测量的累积皮肤剂量和计划剂量在2%以内。放射治疗后6个月的临床检查显示，患者对治疗反应良好，疤痕减少了90%。DSBFD技术结合RapidArc治疗在靶区剂量分布和覆盖方面是有用的。发现每日患者对准非常精确、可重复且耗时较少。
Malignancies with a superficial involvement of the scalp/skull present technical challenges for radiation-treatment-planning, such as achieving skin coverage with the prescribed dose and with the desirable conformity, homogeneity, and lower brain dose. We report a radiotherapy treatment technique for a patient diagnosed with diffuse basosquamous cell carcinoma of the scalp and adjacent skull-bone. This study presents the plan's quality parameters, patient's dosimetry, and patient's outcome. The patient was treated using volume-modulated-arc therapy (VMAT) and a double-shell-bolus full-head device (DSBFD) designed for patient immobilization and better skin coverage. A VMAT plan was generated using an Eclipse treatment-planning system for a prescribed dose of 60 Gy in 30 fractions. The treatment plan was analyzed to determine the conformity index (CI), the homogeneity index (HI), the target-coverage, and the dose to the organs-at-risk (OARs). Skin-doses were measured using optically stimulated luminescence (OSL) dosimeters. Clinical follow-up was performed by the radiation oncologist during and after the course of radiotherapy. With regard to planning target volume (PTV) coverage, the V-95 was 99%. The measured and calculated dose to the skin was in the range 100-108% of the prescribed dose. The mean brain-PTV dose was 711 cGy. The CI and HI were 1.09 and 1.08, respectively. The mean positioning accuracy for the patient over the course of treatment was within 2 mm. The measured accumulated skin dose and planning dose was agreed within 2%. Clinical examination of the patient 6 months after radiotherapy showed good response to the treatment and a 90% reduction in scarring. The DSBFD technique combined with RapidArc treatment was useful in terms of the target dose distribution and coverage. Daily patient alignment was found very precise, reproducible and less time-consuming.