Department of Nuclear Medicine, Cochin Hospital, AP-HP, Paris, France; Université de Paris, Descartes-Paris 5, rue de l'Ecole de Médecine, Paris, France; LITO laboratory, U 1288 Inserm, Institut Curie, Université Paris Saclay, Orsay, France.
Lysa Imaging, Henri Mondor University Hospital, AP-HP, University Paris East, Créteil, France.
Ann Oncol. 2021 Mar;32(3):404-411. doi: 10.1016/j.annonc.2020.11.019. Epub 2020 Dec 3.
We analyzed the prognostic value of a new baseline positron emission tomography (PET) parameter reflecting the spread of the disease, the largest distance between two lesions (Dmax). We tested its complementarity to metabolic tumor volume (MTV) in a large cohort of diffuse large B-cell lymphoma (DLBCL) patients from the REMARC trial (NCT01122472).
MTVs were defined using the 41% maximum standardized uptake value threshold. From the three-dimensional coordinates, the centroid of each lesion was automatically obtained and considered as the lesion location. The distances between all pairs were calculated. Dmax was obtained for each patient and normalized with the body surface area [standardized Dmax (SDmax)].
From the REMARC trial, 290 patients aged 60-80 years were included: 91% had an advanced stage and 71% International Prognostic Index (IPI) ≥3. High versus low SDmax significantly impacted progression-free survival (PFS) (P < 0.0001) and overall survival (OS) (P = 0.0027). Patients with SDmax > 0.32 m (n = 82) had a 4-year PFS and OS of 46% and 71%, respectively, against 77% and 87%, respectively, for patients with low SDmax. High SDmax and high MTV were independent prognostic factors of PFS (P = 0.0001 and P = 0.0010, respectively) and OS (P = 0.0028 and P = 0.0004, respectively). Combining MTV and SDmax yielded three risk groups with no (n = 109), one (n = 122) or two (n = 59) factors (P < 0.0001 for both PFS and OS). The 4-year PFS were 90%, 63%, 41%, respectively, and the 4-year OS were 95%, 79%, 66%, respectively. In addition, patients with at least two of the three factors including high SDmax, high MTV, Eastern Cooperative Oncology Group (ECOG) ≥2 had a higher number of central nervous system relapse (P = 0.017).
SDmax is a simple feature that captures lymphoma dissemination, independent from MTV. These two PET metrics, SDmax and MTV, are complementary to characterize the disease, reflecting the tumor burden and its spread. This score appeared promising for DLBCL baseline risk stratification.
我们分析了一种新的基线正电子发射断层扫描（PET）参数的预后价值，该参数反映了疾病的扩散程度，即两个病变之间的最大距离（Dmax）。我们在 REMARC 试验（NCT01122472）的大量弥漫性大 B 细胞淋巴瘤（DLBCL）患者中测试了它与代谢肿瘤体积（MTV）的互补性。
使用 41%最大标准化摄取值阈值定义 MTV。从三维坐标中，自动获得每个病变的质心，并将其视为病变位置。计算所有对之间的距离。为每个患者获得 Dmax，并按体表面积进行归一化[标准化 Dmax（SDmax）]。
从 REMARC 试验中，纳入了 290 名 60-80 岁的患者：91%为晚期，71%国际预后指数（IPI）≥3。高 SDmax 与低 SDmax 相比，显著影响无进展生存期（PFS）（P < 0.0001）和总生存期（OS）（P = 0.0027）。SDmax > 0.32 m（n = 82）的患者 4 年 PFS 和 OS 分别为 46%和 71%，而 SDmax 低的患者分别为 77%和 87%。高 SDmax 和高 MTV 是 PFS（P = 0.0001 和 P = 0.0010）和 OS（P = 0.0028 和 P = 0.0004）的独立预后因素。MTV 和 SDmax 结合产生了三个风险组，分别为无（n = 109）、一（n = 122）或两（n = 59）个因素（P < 0.0001 用于 PFS 和 OS）。4 年 PFS 分别为 90%、63%、41%，4 年 OS 分别为 95%、79%、66%。此外，至少有两个包括高 SDmax、高 MTV、东部合作肿瘤学组（ECOG）≥2 的三个因素的患者中枢神经系统复发的比例更高（P = 0.017）。
SDmax 是一种简单的特征，可以捕捉淋巴瘤的扩散，与 MTV 无关。这两个 PET 指标，SDmax 和 MTV，相互补充，用于描述疾病，反映肿瘤负荷及其扩散。该评分在 DLBCL 基线风险分层中显示出有希望的结果。
