Avkshtol Vladimir, Meng Boyu, Shen Chenyang, Choi Byong Su, Okoroafor Chikasirimobi, Moon Dominic, Sher David, Lin Mu-Han
Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas.
Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, South Korea.
Adv Radiat Oncol. 2023 Apr 26;8(5):101256. doi: 10.1016/j.adro.2023.101256. eCollection 2023 Sep-Oct.
The advent of cone beam computed tomography-based online adaptive radiation therapy (oART) has dramatically reduced the barriers of adaptation. We present the first prospective oART experience data in radiation of head and neck cancers (HNC).
Patients with HNC receiving definitive standard fractionation (chemo)radiation who underwent at least 1 oART session were enrolled in a prospective registry study. The frequency of adaptations was at the discretion of the treating physician. Physicians were given the option of delivering 1 of 2 plans during adaptation: the original radiation plan transposed onto the cone beam computed tomography with adapted contours (scheduled), and a new adapted plan generated from the updated contours (adapted). A paired test was used to compare the mean doses between scheduled and adapted plans.
Twenty-one patients (15 oropharynx, 4 larynx/hypopharynx, 2 other) underwent 43 adaptation sessions (median, 2). The median ART process time was 23 minutes, median physician time at the console was 27 minutes, and median patient time in the vault was 43.5 minutes. The adapted plan was chosen 93% of the time. The mean volume in each planned target volume (PTV) receiving 100% of the prescription dose for the scheduled versus adapted plan for high-risk PTVs was 87.8% versus 95% ( < .01), intermediate-risk PTVs was 87.3% versus 97.9% ( < .01), and low-risk PTVs was 94% versus 97.8% ( < .01), respectively. The mean hotspot was also lower with adaptation: 108.8% versus 106.4% ( < .01). All but 1 organ at risk (11/12) saw a decrease in their dose with the adapted plans, with the mean ipsilateral parotid ( = .013), mean larynx ( < .01), maximum point spinal cord ( < .01), and maximum point brain stem ( = .035) reaching statistical significance.
Online ART is feasible for HNC, with significant improvement in target coverage and homogeneity and a modest decrease in doses to several organs at risk.
基于锥形束计算机断层扫描的在线自适应放射治疗（oART）的出现极大地降低了适应性障碍。我们展示了头颈部癌（HNC）放射治疗中首个前瞻性oART经验数据。
接受确定性标准分割（化疗）放疗且至少进行过1次oART治疗的HNC患者被纳入一项前瞻性登记研究。适应性治疗的频率由治疗医生自行决定。医生在适应性治疗期间可选择提供2种计划中的1种：将原始放射治疗计划与适应后的轮廓一起转置到锥形束计算机断层扫描图像上（预定计划），以及根据更新后的轮廓生成的新的适应计划（适应计划）。采用配对t检验比较预定计划和适应计划之间的平均剂量。
21例患者（15例口咽癌、4例喉/下咽癌、2例其他癌症）进行了43次适应性治疗（中位数为2次）。ART过程的中位时间为23分钟，医生在控制台的中位时间为27分钟，患者在治疗室的中位时间为43.5分钟。93%的情况下选择了适应计划。对于高风险计划靶体积（PTV），预定计划与适应计划中接受100%处方剂量的每个PTV的平均体积分别为87.8%和95%（P<0.01）；中风险PTV分别为87.3%和97.9%（P<0.01）；低风险PTV分别为94%和97.8%（P<0.01）。适应后平均热点也更低：108.8%和106.4%（P<0.01）。除1个危及器官（12个中的11个）外，所有危及器官的剂量在适应计划中均有所降低，同侧腮腺平均剂量（P=0.013）、喉平均剂量（P<0.01）、脊髓最大点剂量（P<0.01）和脑干最大点剂量（P=0.035）达到统计学显著差异。
在线ART对HNC是可行的，在靶区覆盖和均匀性方面有显著改善，对多个危及器官的剂量有适度降低。
