Wagatsuma Kei, Ikemoto Kensuke, Inaji Motoki, Kamitaka Yuto, Hara Shoko, Tamura Kaoru, Miwa Kenta, Tsuzura Kaede, Tsuruki Taisei, Miyaji Noriaki, Ishibashi Kenji, Ishii Kenji
School of Allied Health Sciences, Kitasato University, 1-15-1 Kitazato, Minami-Ku, Sagamihara, Kanagawa, 252-0373, Japan.
Research Team for Neuroimaging, Tokyo Metropolitan Institute for Geriatrics and Gerontology, 35-2, Sakae-Cho, Itabashi-Ku, Tokyo, 173-0015, Japan.
Ann Nucl Med. 2024 May;38(5):400-407. doi: 10.1007/s12149-024-01911-x. Epub 2024 Mar 11.
The uptake of [C]methionine in positron emission tomography (PET) imaging overlapped in earlier images of tumors. Bayesian penalized likelihood (BPL) reconstruction increases the quantitative values of tumors compared with conventional ordered subset-expectation maximization (OSEM). The present study aimed to grade glioma malignancy based on the new WHO 2021 classification using [C]methionine PET images reconstructed using BPL.
We categorized 32 gliomas in 28 patients as grades 2/3 (n = 15) and 4 (n = 17) based on the WHO 2021 classification. All [C]methionine images were reconstructed using OSEM + time-of-flight (TOF) and BPL + TOF (β = 200). Maximum standardized uptake value (SUV) and tumor-to-normal tissue ratio (T/N) were measured at each lesion.
The mean SUV was 4.65 and 4.93 in grade 2/3 and 6.38 and 7.11 in grade 4, and the mean T/N was 7.08 and 7.22 in grade 2/3 and 9.30 and 10.19 in grade 4 for OSEM and BPL, respectively. The BPL significantly increased these values in grade 4 gliomas. The area under the receiver operator characteristic (ROC) curve (AUC) for SUV was the highest (0.792) using BPL.
The BPL increased mean SUV and mean T/N in lesions with higher contrast such as grade 4 glioma. The discrimination power between grades 2/3 and 4 in SUV was also increased using [C]methionine PET images reconstructed with BPL.
在正电子发射断层扫描（PET）成像中，[碳]蛋氨酸的摄取在肿瘤的早期图像中存在重叠。与传统的有序子集期望最大化（OSEM）相比，贝叶斯惩罚似然（BPL）重建提高了肿瘤的定量值。本研究旨在基于2021年世界卫生组织（WHO）新分类，使用BPL重建的[碳]蛋氨酸PET图像对胶质瘤的恶性程度进行分级。
根据WHO 2021年分类，我们将28例患者的32个胶质瘤分为2/3级（n = 15）和4级（n = 17）。所有[碳]蛋氨酸图像均使用OSEM + 飞行时间（TOF）和BPL + TOF（β = 200）进行重建。在每个病灶处测量最大标准化摄取值（SUV）和肿瘤与正常组织比值（T/N）。
对于OSEM和BPL，2/3级的平均SUV分别为4.65和4.93，4级的平均SUV分别为6.38和7.11；2/3级的平均T/N分别为7.08和7.22，4级的平均T/N分别为9.30和10.19。BPL显著提高了4级胶质瘤的这些值。使用BPL时，SUV的受试者操作特征（ROC）曲线下面积（AUC）最高（0.792）。
BPL提高了4级胶质瘤等高对比度病灶的平均SUV和平均T/N。使用BPL重建的[碳]蛋氨酸PET图像也提高了SUV在2/3级和4级之间的鉴别能力。
