Department of Nuclear Medicine, Oncology Institute of Southern Switzerland, Bellinzona, Switzerland.
Clin Nucl Med. 2012 Oct;37(10):949-52. doi: 10.1097/RLU.0b013e318263831d.
The main objective of this study was to assess the intrasubject and intersubjects variability of 18F-FDG uptake in liver (LIV) and mediastinum (MBP) among patients with diffuse large B-cell lymphoma (DLBCL), treated with different chemotherapy regimens.
Fifty patients with DLBCL who underwent 18F-FDG PET/CT scan at baseline, after a few cycles of therapy (interim PET) and on completion of therapy (final PET), were enrolled retrospectively. SUVmean and SUVmax values for LIV and MBP, their differences (LIV - MBP SUVmean and LIV - MBP SUVmax), and their changes were calculated, respectively.
Liver uptake significantly increased in the interim in comparison with baseline and final PET, respectively, whereas MBP activity remained stable during chemotherapy. The intersubject variability of 18F-FDG uptake in LIV and MBP ranged from 20.2% to 25.4%.
The variability of the LIV uptake during chemotherapy should be taken into account when this parameter is used to score the interim PET scan and to make decisions in defining response-adapted therapeutic strategies. Vice versa, the stability of MBP activity during therapy provides a more reliable benchmark for the response assessment.Finally, the intersubjects variability of both parameters should be considered when the visual evaluation of the interim PET is performed by point score models.
本研究的主要目的是评估接受不同化疗方案治疗的弥漫性大 B 细胞淋巴瘤（DLBCL）患者中肝脏（LIV）和纵隔（MBP）18F-FDG 摄取的个体内和个体间变异性。
回顾性纳入 50 例基线、几个疗程后（中期 PET）和治疗结束时（最终 PET）行 18F-FDG PET/CT 扫描的 DLBCL 患者。分别计算 LIV 和 MBP 的 SUVmean 和 SUVmax 值、两者之间的差异（LIV-MBP SUVmean 和 LIV-MBP SUVmax）以及变化值。
与基线和最终 PET 相比，中期 PET 时肝脏摄取明显增加，而 MBP 活性在化疗期间保持稳定。LIV 和 MBP 中 18F-FDG 摄取的个体间变异性范围为 20.2%-25.4%。
在使用该参数对中期 PET 扫描进行评分并制定反应适应性治疗策略时，应考虑化疗期间 LIV 摄取的变异性。相反，治疗期间 MBP 活性的稳定性为反应评估提供了更可靠的基准。最后，当使用点评分模型进行中期 PET 的视觉评估时，应考虑这两个参数的个体间变异性。
