Li Yucheng, Zhan Wenming, Jia Yongshi, Xiong Hanchu, Lin Baihua, Li Qiang, Liu Huaxin, Qiu Lingyun, Zhang Yinghao, Ding Jieni, Fu Chao, Chen Weijun
Cancer Center, Department of Radiation Oncology, Zhejiang Provincial People's Hospital, Affiliated People's Hospital, Hangzhou Medical College, Hangzhou, Zhejiang, China.
Department of Tumor Radiochemotherapy, Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
Front Oncol. 2023 Aug 18;13:1145332. doi: 10.3389/fonc.2023.1145332. eCollection 2023.
To explore the advantages of dosimetry and the treatment efficiency of tangent-arc technology in deep inspiration breath-hold radiotherapy for breast cancer.
Forty patients with left-sided breast cancer who were treated in our hospital from May 2020 to June 2021 were randomly selected and divided into two groups. The first group's plan was a continuous semi-arc that started at 145° ( ± 5°) and stopped at 325° ( ± 5°). The other group's plan, defined as the tangent-arc plan, had two arcs: the first arc started at 145° ( ± 5°) and stopped at 85° ( ± 5°), and the second arc started at 25° ( ± 5°) and stopped at 325° ( ± 5°). We compared the target dose, dose in organs at risk (OARs), and treatment time between the two groups.
The target dose was similar between the continuous semiarc and tangent-arc groups. The V of the right lung was significantly different between the two groups (Dif 5.52, 95% confidence interval 1.92-9.13, =3.10, =0.004), with the patients in the continuous semi-arc and tangent-arc groups having lung V values of (9.16 ± 1.62)%, and (3.64 ± 0.73)%, respectively. The maximum dose to the spinal cord was (1835.88 ± 222.17) cGy in the continuous semi-arc group and (599.42 ± 153.91) cGy in the tangent-arc group, yielding a significant difference between the two groups (Dif 1236.46, 95% confidence interval 689.32-1783.6, =4.57, <0.001). The treatment times was (311.70 ± 60.45) s for patients in the continuous semi-arc group and (254.66 ± 40.73) s for patients in the tangent-arc group, and there was a significant difference in the mean number of treatment times between the two groups (Dif 57.04, 95% confidence interval 24.05-90.03, =3.5, =0.001).
Both the continuous semi-arc and tangent-arc plans met the clinical prescription dose requirements. The OARs received less radiation with the tangent-arc plan than the continuous semi-arc plan, especially for the lung (measured as V) and the spinal cord (measured as the maximum dose). Tangent-arc plan took significantly less time than the continuous semi-arc, which can greatly improve treatment efficiency. Therefore, tangent-arc plans are superior continuous semi-arc plans for all cases.
探讨剂量测定的优势以及切线弧技术在乳腺癌深吸气屏气放疗中的治疗效率。
随机选取2020年5月至2021年6月在我院接受治疗的40例左侧乳腺癌患者，分为两组。第一组计划为连续半弧，起始角度为145°（±5°），终止角度为325°（±5°）。另一组计划为切线弧计划，有两个弧段：第一个弧段起始角度为145°（±5°），终止角度为85°（±5°），第二个弧段起始角度为25°（±5°），终止角度为325°（±5°）。比较两组的靶区剂量、危及器官（OARs）剂量和治疗时间。
连续半弧组和切线弧组的靶区剂量相似。两组右肺的V值有显著差异（差异为5.52，95%置信区间为1.92 - 9.13，t = 3.10，P = 0.004），连续半弧组和切线弧组患者的肺V值分别为（9.16 ± 1.62）%和（3.64 ± 0.73）%。连续半弧组脊髓的最大剂量为（1835.88 ± 222.17）cGy，切线弧组为（599.42 ± 153.91）cGy，两组间有显著差异（差异为1236.46，95%置信区间为689.32 - 1783.6，t = 4.57，P < 0.001）。连续半弧组患者的治疗时间为（311.70 ± 60.45）秒，切线弧组患者为（254.66 ± 40.73）秒，两组平均治疗次数有显著差异（差异为57.04，95%置信区间为24.05 - 90.03，t = 3.5，P = 0.001）。
连续半弧计划和切线弧计划均满足临床处方剂量要求。与连续半弧计划相比，切线弧计划使危及器官接受的辐射更少，尤其是肺（以V值衡量）和脊髓（以最大剂量衡量）。切线弧计划的治疗时间明显短于连续半弧计划，可大大提高治疗效率。因此，在所有情况下，切线弧计划优于连续半弧计划。
