Zheng Xiao-Kang, Chen Long-Hua, Wang Quan-Shi, Wu Fu-Bing
Department of Radiation Oncology, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China.
Int J Radiat Oncol Biol Phys. 2006 Jul 15;65(4):1020-5. doi: 10.1016/j.ijrobp.2006.02.037. Epub 2006 May 26.
The purpose of this study was to evaluate the role of [18F] fluorodeoxyglucose positron emission tomography (FDG-PET) in influencing salvage treatment decision making for locally persistent nasopharyngeal carcinoma (NPC).
A total of 33 NPC patients with histologic persistence at nasopharynx 1 to 6 weeks after a full course of radiotherapy underwent both computed tomography (CT) and FDG-PET/CT simulation at the same treatment position. The salvage treatment decisions, with regard to the decision to offer salvage treatment and the definition of gross tumor volume (GTV), were made before knowledge of the FDG-PET findings. Subsequently the salvage treatment decisions were made again based on the FDG-PET findings and compared with the pre-FDG-PET decisions.
All 33 patients were referred for salvage treatment in the pre-FDG-PET decision. After knowledge of the FDG-PET results, the decision to offer salvage treatment was withdrawn in 4 of 33 patients (12.1%), as no abnormal uptake of FDG was found at nasopharynx. Spontaneous remission was observed in repeat biopsies and no local recurrence was found in these 4 cases. For the remaining 29 patients, GTV based on FDG-PET was smaller than GTV based on CT in 24 (82.8%) cases and was greater in 5 (17.2%) cases, respectively. The target volume had to be significantly modified in 9 of 29 patients (31%), as GTV based on FDG-PET images failed to be enclosed by the treated volume in the salvage treatment plan performed based on GTV based on CT simulation images.
Use of FDG-PET was found to influence the salvage treatment decision making for locally persistent NPC by identifying patients who were not likely to benefit from additional treatment and by improving accuracy of GTV definition in salvage treatment planning.
本研究旨在评估[18F]氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）在影响局部持续性鼻咽癌（NPC）挽救治疗决策中的作用。
33例NPC患者在完成一个疗程放疗后1至6周鼻咽部组织学呈持续性病变，在相同治疗部位接受了计算机断层扫描（CT）和FDG-PET/CT模拟。在知晓FDG-PET检查结果之前，做出关于是否提供挽救治疗的决策以及大体肿瘤体积（GTV）的定义。随后，根据FDG-PET检查结果再次做出挽救治疗决策，并与FDG-PET检查前的决策进行比较。
在FDG-PET检查前的决策中，所有33例患者均被推荐进行挽救治疗。在知晓FDG-PET结果后，33例患者中有4例（12.1%）撤回了提供挽救治疗的决策，因为在鼻咽部未发现FDG异常摄取。在重复活检中观察到自发缓解，这4例患者未发现局部复发。对于其余29例患者，基于FDG-PET的GTV在24例（82.8%）中小于基于CT的GTV，在5例（17.2%）中大于基于CT的GTV。29例患者中有9例（31%）的靶区体积必须进行显著修改，因为基于FDG-PET图像的GTV在基于CT模拟图像的GTV所制定的挽救治疗计划中未能被治疗体积所覆盖。
发现使用FDG-PET可通过识别不太可能从额外治疗中获益的患者以及提高挽救治疗计划中GTV定义的准确性，来影响局部持续性NPC的挽救治疗决策。
