Woods Kaley, Chin Robert K, Cook Kiri A, Sheng Ke, Kishan Amar U, Hegde John V, Tenn Stephen, Steinberg Michael L, Cao Minsong
Department of Radiation Oncology, University of California, Los Angeles, CA 90095, USA.
Department of Radiation Oncology, Oregon Health & Science University, Portland, OR 97239, USA.
Cancers (Basel). 2021 Apr 15;13(8):1910. doi: 10.3390/cancers13081910.
This study evaluates the potential for tumor dose escalation in recurrent head and neck cancer (rHNC) patients with automated non-coplanar volumetric modulated arc therapy (VMAT) stereotactic body radiation therapy (SBRT) planning (HyperArc). Twenty rHNC patients are planned with conventional VMAT SBRT to 40 Gy while minimizing organ-at-risk (OAR) doses. They are then re-planned with the HyperArc technique to match these minimal OAR doses while escalating the target dose as high as possible. Then, we compare the dosimetry, tumor control probability (TCP), and normal tissue complication probability (NTCP) for the two plan types. Our results show that the HyperArc technique significantly increases the mean planning target volume (PTV) and gross tumor volume (GTV) doses by 10.8 ± 4.4 Gy (25%) and 11.5 ± 5.1 Gy (26%) on average, respectively. There are no clinically significant differences in OAR doses, with maximum dose differences of <2 Gy on average. The average TCP is 23% (± 21%) higher for HyperArc than conventional plans, with no significant differences in NTCP for the brainstem, cord, mandible, or larynx. HyperArc can achieve significant tumor dose escalation while maintaining minimal OAR doses in the head and neck-potentially enabling improved local control for rHNC SBRT patients without increased risk of treatment-related toxicities.
本研究评估了采用自动非共面容积调强弧形治疗(VMAT)立体定向体部放射治疗(SBRT)计划(HyperArc)对复发性头颈癌(rHNC)患者进行肿瘤剂量递增的潜力。20例rHNC患者采用传统VMAT SBRT计划照射至40 Gy,同时尽量降低危及器官(OAR)剂量。然后采用HyperArc技术重新计划,以匹配这些最低OAR剂量,同时尽可能提高靶区剂量。然后,我们比较两种计划类型的剂量学、肿瘤控制概率(TCP)和正常组织并发症概率(NTCP)。我们的结果表明,HyperArc技术平均显著提高了平均计划靶体积(PTV)和大体肿瘤体积(GTV)剂量,分别提高了10.8±4.4 Gy(25%)和11.5±5.1 Gy(26%)。OAR剂量没有临床显著差异,平均最大剂量差异<2 Gy。HyperArc的平均TCP比传统计划高23%(±21%),脑干、脊髓、下颌骨或喉部的NTCP没有显著差异。HyperArc可以在保持头颈最低OAR剂量的同时实现显著的肿瘤剂量递增,这可能使rHNC SBRT患者的局部控制得到改善,而不会增加与治疗相关的毒性风险。