Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland
Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, Maryland.
J Nucl Med. 2020 Nov;61(11):1570-1575. doi: 10.2967/jnumed.119.238733. Epub 2020 Apr 13.
Cancer survival is related to tumor volume. F-FDG PET measurement of tumor volume holds promise but is not yet a clinical tool. Measurements come in 2 forms: the first is total lesion volume (TLV) based on the number of voxels in the tumor, and the second is total lesion glycolysis (TLG), which is the TLV multiplied by the average SUL (i.e., SUV normalized for lean mass) of the tumor (SUL). In this study, we measured tumor volume in patients with malignant pleural mesothelioma (MPM). A threshold-based program in Interactive Data Language was developed to measure tumor volume in F-FDG PET images. Nineteen patients with MPM were studied before and after 2 cycles (6 wk) of chemoimmunotherapy. Measurements included TLV, TLG, the sum of the SULs in the tumor (SUL, a measure of total F-FDG uptake), and SUL Baseline TLV ranged from 11 to 2,610 cm TLG ranged from 32 to 8,552 cm g/mL and correlated strongly with TLV. Although tumor volumes ranged over 3 orders of magnitude, SUL stayed within a narrow range of 2.4-5.3 units. Thus, TLV was the major component of TLG, whereas SUL was a minor component and was essentially constant. Further evaluation of SUL showed that in this cohort its 2 components, SUL and TLV, changed in parallel and were strongly correlated ( = 0.99, < 0.01). Thus, whether the tumors were large or small, F-FDG uptake as measured by SUL was proportional to the TLV. TLG equals TLV multiplied by SUL, essentially TLV multiplied by a constant. Thus TLG, commonly considered a measure of metabolic activity in tumors, is also in this cohort a measure of tumor volume. The constancy of SUL is due to the fact that F-FDG uptake is proportional to tumor volume. Thus, in this study, F-FDG uptake was also a measure of volume.
癌症存活率与肿瘤体积有关。使用 F-FDG PET 测量肿瘤体积具有一定的前景，但尚未成为临床工具。这种测量有两种形式：第一种是基于肿瘤内体素数量的总病灶体积（TLV），第二种是总病灶糖酵解（TLG），它是 TLV 与肿瘤平均 SUL（即标准化为瘦体重的 SUV）的乘积（SUL）。在这项研究中，我们测量了恶性胸膜间皮瘤（MPM）患者的肿瘤体积。我们使用交互式数据语言中的一个基于阈值的程序来测量 F-FDG PET 图像中的肿瘤体积。19 名 MPM 患者在接受 2 个周期（6 周）化疗免疫治疗前后接受了研究。测量包括 TLV、TLG、肿瘤中 SUL 的总和（SUL，是总 F-FDG 摄取的度量）和 SUL 基线 TLV 范围从 11 到 2610cm³，TLG 范围从 32 到 8552cm³/g/mL，与 TLV 呈强相关。尽管肿瘤体积范围超过 3 个数量级，但 SUL 仍保持在 2.4-5.3 个单位的狭窄范围内。因此，TLV 是 TLG 的主要组成部分，而 SUL 是次要组成部分，基本上是恒定的。进一步评估 SUL 表明，在本队列中，其两个组成部分，SUL 和 TLV，平行变化且呈强相关（=0.99，<0.01）。因此，无论肿瘤是大是小，SUL 测量的 F-FDG 摄取量与 TLV 成正比。TLG 等于 TLV 乘以 SUL，本质上是 TLV 乘以常数。因此，在本队列中，TLG 通常被认为是肿瘤代谢活性的度量，也是肿瘤体积的度量。SUL 的恒定性是由于 F-FDG 摄取量与肿瘤体积成正比的事实。因此，在这项研究中，F-FDG 摄取量也是体积的一种度量。
