Department of Nuclear Medicine, Henri Becquerel Cancer Centre, Rue d'Amiens - CS 11516, 76038, Rouen Cedex 1, France.
LITIS Quantif-EA4108, University of Rouen, Rouen, France.
Eur J Nucl Med Mol Imaging. 2018 Sep;45(10):1672-1679. doi: 10.1007/s00259-018-4041-0. Epub 2018 Apr 28.
Our aim was to study the prognostic value of two new F-FDG PET biomarkers in diffuse large B-cell lymphoma (DLBCL). We examined the total tumor surface (TTS), describing the tumor-host interface, and the tumor volume surface ratio (TVSR), corresponding to the ratio between the total metabolic tumor volume (TMTV) and TTS, describing the tumor fragmentation.
We retrospectively included 215 patients with DLBCL. Patients underwent initial F-FDG PET/CT before R-CHOP (73%) or intensified R-CHOP (R-ACVBP) regimens (27%). The TMTV was measured using a fixed threshold value of 41% of SUVmax. To calculate TTS and TVSR, the surface was measured using an in-house software based on the marching cube algorithm. Spearman's rank correlation coefficient (ρ) was computed between TMTV, TTS, and TVSR, and ROC analysis was performed. Survival functions at 5 years were studied using a Kaplan-Meier method and uni/multivariate Cox analysis.
TVSR was poorly correlated with TMTV (ρ = 0.5) and TTS (ρ = 0.26), while TTS was highly correlated with TMTV (ρ = 0.94) and was, therefore, excluded from the analysis. TMTV had the highest area under the ROC curve (0.711) and the best sensitivity (0.797), while TVSR had the best specificity (0.745). The optimal cut-off values to predict 5-year OS were 222 cm for TMTV and 6.0 mm for TVSR. Patients with high TMTV and TVSR had significantly worse prognosis in Kaplan-Meier and Cox univariate analysis. In a multivariate Cox analysis combining the International Prognostic Index (IPI), the type of chemotherapy, TMTV, and TVSR, all parameters were independent and significant prognostic factors (HR [95%CI]: IPI 1.4 [1.1-1.8], type of chemotherapy 4.5 [2.0-10.5], TMTV 2.8 [1.4-5.5], TVSR 2.1 [1.3-3.4]). A synergistic effect between TMTV and TVSR was observed in a Kaplan-Meier analysis combining the two parameters.
TVSR measured on the initial F-FDG PET is an independent prognostic factor in DLBCL and has an additional prognostic value when combined with TMTV, IPI score and chemotherapy.
我们的目的是研究两种新的 F-FDG PET 生物标志物在弥漫性大 B 细胞淋巴瘤 (DLBCL) 中的预后价值。我们研究了总肿瘤表面积 (TTS)，用于描述肿瘤-宿主界面，以及肿瘤体积表面积比 (TVSR)，它对应于总代谢肿瘤体积 (TMTV)与 TTS 的比值，用于描述肿瘤碎裂程度。
我们回顾性纳入了 215 例 DLBCL 患者。患者在 R-CHOP（73%）或强化 R-CHOP（R-ACVBP）方案（27%）之前接受了初始 F-FDG PET/CT 检查。使用 SUVmax 的 41%的固定阈值来测量 TMTV。为了计算 TTS 和 TVSR，使用基于体素空间填充算法的内部软件测量表面积。使用 Spearman 秩相关系数 (ρ) 计算 TMTV、TTS 和 TVSR 之间的相关性，并进行 ROC 分析。使用 Kaplan-Meier 方法和单变量/多变量 Cox 分析研究 5 年生存功能。
TVSR 与 TMTV（ρ=0.5）和 TTS（ρ=0.26）的相关性较差，而 TTS 与 TMTV 高度相关（ρ=0.94），因此排除在分析之外。TMTV 具有最高的 ROC 曲线下面积 (0.711) 和最佳敏感性 (0.797)，而 TVSR 具有最佳特异性 (0.745)。预测 5 年 OS 的最佳截断值为 TMTV 为 222cm，TVSR 为 6.0mm。Kaplan-Meier 和 Cox 单变量分析显示，TMTV 和 TVSR 较高的患者预后明显较差。在多变量 Cox 分析中，将国际预后指数 (IPI)、化疗类型、TMTV 和 TVSR 结合在一起，所有参数均为独立且重要的预后因素（HR [95%CI]：IPI 1.4 [1.1-1.8]，化疗类型 4.5 [2.0-10.5]，TMTV 2.8 [1.4-5.5]，TVSR 2.1 [1.3-3.4]）。在结合两个参数的 Kaplan-Meier 分析中观察到 TMTV 和 TVSR 之间的协同作用。
在 DLBCL 中，初始 F-FDG PET 上测量的 TVSR 是独立的预后因素，与 TMTV、IPI 评分和化疗联合具有额外的预后价值。
