Mohamed Abdallah S R, Cardenas Carlos E, Garden Adam S, Awan Musaddiq J, Rock Crosby D, Westergaard Sarah A, Brandon Gunn G, Belal Abdelaziz M, El-Gowily Ahmed G, Lai Stephen Y, Rosenthal David I, Fuller Clifton D, Aristophanous Michalis
Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA; Department of Clinical Oncology and Nuclear Medicine, Faculty of Medicine, University of Alexandria, Egypt.
Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, USA.
Radiother Oncol. 2017 Aug;124(2):248-255. doi: 10.1016/j.radonc.2017.07.017. Epub 2017 Jul 31.
To identify the radio-resistant subvolumes in pretreatment FDG-PET by mapping the spatial location of the origin of tumor recurrence after IMRT for head-and-neck squamous cell cancer to the pretreatment FDG-PET/CT.
Patients with local/regional recurrence after IMRT with available FDG-PET/CT and post-failure CT were included. For each patient, both pre-therapy PET/CT and recurrence CT were co-registered with the planning CT (pCT). A 4-mm radius was added to the centroid of mapped recurrence growth target volumes (rGTV's) to create recurrence nidus-volumes (NVs). The overlap between boost-tumor-volumes (BTV) representing different SUV thresholds/margins combinations and NVs was measured.
Forty-seven patients were eligible. Forty-two (89.4%) had type A central high dose failure. Twenty-six (48%) of type A rGTVs were at the primary site and 28 (52%) were at the nodal site. The mean dose of type A rGTVs was 71Gy. BTV consisting of 50% of the maximum SUV plus 10mm margin was the best subvolume for dose boosting due to high coverage of primary site NVs (92.3%), low average relative volume to CTV1 (41%), and least average percent voxels outside CTV1 (19%).
The majority of loco-regional recurrences originate in the regions of central-high-dose. When correlated with pretreatment FDG-PET, the majority of recurrences originated in an area that would be covered by additional 10mm margin on the volume of 50% of the maximum FDG uptake.
通过将头颈部鳞状细胞癌调强放疗（IMRT）后肿瘤复发起源的空间位置映射到治疗前的氟代脱氧葡萄糖正电子发射断层扫描（FDG-PET），以识别治疗前FDG-PET中的放射抗拒子体积。
纳入IMRT后出现局部/区域复发且有可用的FDG-PET/CT和失败后CT的患者。对于每位患者，治疗前PET/CT和复发CT均与计划CT（pCT）进行配准。在映射的复发生长靶体积（rGTV）的质心处添加4毫米半径，以创建复发病灶体积（NV）。测量代表不同SUV阈值/边界组合的增强肿瘤体积（BTV）与NV之间的重叠。
47例患者符合条件。42例（89.4%）为A型中心高剂量失败。26例（48%）A型rGTV位于原发部位，28例（52%）位于淋巴结部位。A型rGTV的平均剂量为71Gy。由最大SUV的50%加10毫米边界组成的BTV是剂量增强的最佳子体积，因为其对原发部位NV的覆盖率高（92.3%），相对于CTV1的平均相对体积低（41%），且CTV1外的平均体素百分比最少（19%）。
大多数局部区域复发起源于中心高剂量区域。当与治疗前FDG-PET相关联时，大多数复发起源于最大FDG摄取量的50%体积上额外10毫米边界所覆盖的区域。
