Division of Nuclear Medicine, Department of Radiology, National Center for Global Health and Medicine, 1-21-1, Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan.
Department of Surgery, National Center for Global Health and Medicine, 1-21-1, Toyama, Shinjuku-ku, Tokyo, 162-8655, Japan.
Ann Nucl Med. 2021 Jul;35(7):843-852. doi: 10.1007/s12149-021-01622-7. Epub 2021 May 4.
The aim of this study was to evaluate the ability of texture analysis using pretreatment F-FDG PET/CT to predict prognosis in patients with surgically treated rectal cancer.
We analyzed 94 patients with pathologically proven rectal cancer who underwent pretreatment F-FDG PET/CT and were subsequently treated with surgery. The volume of interest of the primary tumor was defined using a threshold of 40% of the maximum standardized uptake value (SUVmax), and conventional (SUVmax, metabolic tumor volume [MTV], total lesion glycolysis [TLG]) and textural PET features were extracted. Harmonization of PET features was performed with the ComBat method. The study endpoints were overall survival (OS) and progression-free survival (PFS), and the prognostic value of PET features was evaluated by Cox regression analysis.
In the follow-up period (median 41.7 [interquartile range, 30.5-60.4] months), 21 (22.3%) and 30 (31.9%) patients had cancer-related death or disease progression, respectively. Univariate analysis revealed a significant association of (1) MTV, TLG, and gray-level co-occurrence matrix (GLCM) entropy with OS; and (2) SUVmax, MTV, TLG, and GLCM entropy with PFS. In multivariate analysis including clinical characteristics, GLCM entropy (≥ 2.13) was the only relevant prognostic PET feature for poor OS (hazard ratio [HR]: 4.16, p = 0.035) and PFS (HR: 2.70, p = 0.046).
GLCM entropy, which indicates metabolic intratumoral heterogeneity, was an independent prognostic factor in patients with surgically treated rectal cancer. Compared with conventional PET features, GLCM entropy has better predictive value and shows potential to facilitate precision medicine.
本研究旨在评估预处理 F-FDG PET/CT 纹理分析预测接受手术治疗的直肠癌患者预后的能力。
我们分析了 94 例经病理证实的直肠癌患者，这些患者均行术前 F-FDG PET/CT 检查，随后接受手术治疗。使用最大标准化摄取值（SUVmax）的 40%作为阈值，定义原发肿瘤的感兴趣容积，提取常规（SUVmax、代谢肿瘤体积 [MTV]、总病变糖酵解 [TLG]）和纹理 PET 特征。采用 ComBat 方法进行 PET 特征的协调。研究终点为总生存（OS）和无进展生存（PFS），通过 Cox 回归分析评估 PET 特征的预后价值。
在随访期间（中位数 41.7[四分位距 30.5-60.4]个月），分别有 21（22.3%）和 30（31.9%）例患者发生癌症相关死亡或疾病进展。单因素分析显示，（1）MTV、TLG 和灰度共生矩阵（GLCM）熵与 OS 相关；（2）SUVmax、MTV、TLG 和 GLCM 熵与 PFS 相关。在包括临床特征的多因素分析中，GLCM 熵（≥2.13）是与 OS（风险比 [HR]：4.16，p=0.035）和 PFS（HR：2.70，p=0.046）不良相关的唯一预测性 PET 特征。
GLCM 熵（表示肿瘤内代谢异质性）是接受手术治疗的直肠癌患者的独立预后因素。与常规 PET 特征相比，GLCM 熵具有更好的预测价值，有望促进精准医疗。
