Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
Radiother Oncol. 2014 Nov;113(2):188-92. doi: 10.1016/j.radonc.2014.10.016. Epub 2014 Nov 29.
The aim of this prospective study was to determine the proportion of locoregional recurrences (LRRs) that could have been prevented if radiotherapy treatment planning for oesophageal cancer was based on PET/CT instead of CT.
Ninety oesophageal cancer patients, eligible for high dose (neo-adjuvant) (chemo)radiotherapy, were included. All patients underwent a planning FDG-PET/CT-scan. Radiotherapy target volumes (TVs) were delineated on CT and patients were treated according to the CT-based treatment plans. The PET images remained blinded. After treatment, TVs were adjusted based on PET/CT, when appropriate. Follow up included CT-thorax/abdomen every 6months. If LRR was suspected, a PET/CT was conducted and the site of recurrence was compared to the original TVs. If the LRR was located outside the CT-based clinical TV (CTV) and inside the PET/CT-based CTV, we considered this LRR possibly preventable.
Based on PET/CT, the gross tumour volume (GTV) was larger in 23% and smaller in 27% of the cases. In 32 patients (36%), >5% of the PET/CT-based GTV would be missed if the treatment planning was based on CT. The median follow up was 29months. LRRs were seen in 10 patients (11%). There were 3 in-field recurrences, 4 regional recurrences outside both CT-based and PET/CT-based CTV and 3 recurrences at the anastomosis without changes in TV by PET/CT; none of these recurrences were considered preventable by PET/CT.
No LRR was found after CT-based radiotherapy that could have been prevented by PET/CT. The value of PET/CT for radiotherapy seems limited.
本前瞻性研究旨在确定如果食管癌的放射治疗计划基于 PET/CT 而不是 CT，有多少局部区域复发（LRR）可以预防。
纳入 90 例适合高剂量（新辅助）（放化疗）的食管癌患者。所有患者均行 FDG-PET/CT 扫描。在 CT 上勾画放射治疗靶区（TV），并根据 CT 制定的治疗计划进行治疗。PET 图像保持盲法。治疗后，根据 PET/CT 调整 TV，如有必要。随访包括每 6 个月进行一次胸部/腹部 CT。如果怀疑有 LRR，进行 PET/CT 检查，并将复发部位与原始 TV 进行比较。如果 LRR 位于 CT 基临床靶区（CTV）内且位于 PET/CT 基 CTV 内，我们认为这是可能预防的 LRR。
基于 PET/CT，23%的病例肿瘤总体积（GTV）增大，27%的病例 GTV 减小。在 32 例（36%）患者中，如果治疗计划基于 CT，将错过>5%的基于 PET/CT 的 GTV。中位随访时间为 29 个月。10 例患者（11%）出现 LRR。3 例为场内复发，4 例为 CT 基和 PET/CT 基 CTV 以外的区域复发，3 例为吻合口复发，PET/CT 无 TV 改变；这些复发均未被认为可通过 PET/CT 预防。
基于 CT 的放射治疗后未发现可通过 PET/CT 预防的 LRR。PET/CT 对放射治疗的价值似乎有限。
