Messerli Michael, Kotasidis Fotis, Burger Irene A, Ferraro Daniela A, Muehlematter Urs J, Weyermann Corina, Kenkel David, von Schulthess Gustav K, Kaufmann Philipp A, Huellner Martin W
1 Department of Nuclear Medicine, University Hospital Zurich / University of Zurich , Switzerland.
2 GE Healthcare , Waukesha, WI , USA.
Br J Radiol. 2019 Apr;92(1096):20180792. doi: 10.1259/bjr.20180792. Epub 2019 Feb 26.
: Positron emission tomography (PET) using F-fludeoxyglucose (F-FDG) is an established imaging modality for tumor staging in patients with non-small cell lung cancer (NSCLC). There is a growing interest in using F-FDG PET for therapy response assessment in NSCLC which relies on quantitative PET parameters such as standardized uptake values (SUV). Different reconstruction algorithms in PET may affect SUV. We sought to determine the variation of SUV in patients with NSCLC when using ordered subset expectation maximization (OSEM) and block sequential regularized expectation maximization (BSREM) in latest-generation digital PET/CT, including a subanalysis for adenocarcinoma and squamous cell carcinoma.
: A total of 58 patients (34 = adenocarcinoma, 24 = squamous cell carcinoma) who underwent a clinically indicated F-FDG PET/CT for staging were reviewed. PET images were reconstructed with OSEM and BSREM reconstruction with noise penalty strength β-levels of 350, 450, 600, 800 and 1200. Lung tumors maximum standardized uptake value (SUV) were compared.
: Lung tumors SUV were significantly lower in adenocarcinomas compared to squamous cell carcinomas in all reconstructions evaluated (all p < 0.01). Comparing BSREM to OSEM, absolute SUV differences were highest in lower β-levels of BSREM with + 2.9 ± 1.6 in adenocarcinoma and + 4.0 ± 2.9 in squamous cell carcinoma (difference between histology; p-values > 0.05). There was a statistically significant difference of the relative increase of SUV in adenocarcinoma (mean + 34.8%) and squamous cell carcinoma (mean 23.4%), when using BSREM instead of OSEM (p < 0.05).
: In NSCLC the relative change of SUV when using BSREM instead of OSEM is significantly higher in adenocarcinoma as compared to squamous cell carcinoma.
: The impact of BSREM on SUV may vary in different histological subtypes of NSCLC. This highlights the importance for careful standardization of β-value used for serial F-FDG PET scans when following-up NSCLC patients.
使用氟代脱氧葡萄糖（F-FDG）的正电子发射断层扫描（PET）是用于非小细胞肺癌（NSCLC）患者肿瘤分期的既定成像方式。使用F-FDG PET进行NSCLC治疗反应评估的兴趣日益增加，这依赖于定量PET参数，如标准化摄取值（SUV）。PET中不同的重建算法可能会影响SUV。我们试图确定在最新一代数字PET/CT中使用有序子集期望最大化（OSEM）和块序贯正则化期望最大化（BSREM）时NSCLC患者SUV的变化，包括对腺癌和鳞状细胞癌的亚分析。
回顾了总共58例因分期而接受临床指征的F-FDG PET/CT检查的患者（34例腺癌，24例鳞状细胞癌）。PET图像用OSEM和BSREM重建，噪声惩罚强度β水平为350、450、600、800和1200。比较肺肿瘤的最大标准化摄取值（SUV）。
在所有评估的重建中，腺癌的肺肿瘤SUV显著低于鳞状细胞癌（所有p<0.01）。将BSREM与OSEM比较，在BSREM的较低β水平下，绝对SUV差异最高，腺癌为+2.9±1.6，鳞状细胞癌为+4.0±2.9（组织学之间的差异；p值>0.05）。当使用BSREM而非OSEM时，腺癌（平均+34.8%）和鳞状细胞癌（平均23.4%）的SUV相对增加存在统计学显著差异（p<0.05）。
在NSCLC中，与鳞状细胞癌相比，使用BSREM而非OSEM时腺癌SUV的相对变化显著更高。
BSREM对SUV的影响在NSCLC的不同组织学亚型中可能有所不同。这突出了在随访NSCLC患者时，对用于系列F-FDG PET扫描的β值进行仔细标准化的重要性。
