Department of Nuclear Medicine, University Hospital Würzburg, Oberdürrbacher Strasse 6, 97080, Würzburg, Germany.
Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
Mol Imaging Biol. 2023 Aug;25(4):758-764. doi: 10.1007/s11307-023-01830-9. Epub 2023 Jun 7.
Recent studies investigating a tumor-sink effect in solid tumors reported on decreasing uptake in normal organs in patients with higher tumor burden. This phenomenon, however, has not been evaluated yet for theranostic radiotracers applied to hematological neoplasms. As such, we aimed to determine a potential "lymphoma-sink effect" in patients with marginal zone lymphoma (MZL) imaged with C-X-C motif chemokine receptor (CXCR) 4-directed PET/CTs.
We retrospectively analyzed 73 patients with MZL who underwent CXCR4-directed [Ga]Ga-PentixaFor PET/CT. Normal unaffected organ uptake (heart, liver, spleen, bone marrow, kidneys) was quantified using volumes of interests (VOIs) and mean standardized uptake values (SUV) were derived. MZL manifestations were also segmented to determine the maximum and peak standardized uptake values SUV (SUV) and volumetric parameters, including lymphoma volume (LV), and fractional lymphoma activity (FLA, defined as LV*SUV of lymphoma burden). This approach resulted in 666 VOIs to capture the entire MZL manifestation load. We used Spearman's rank correlations to determine associations between organ uptake and CXCR4-expressing lymphoma lesions.
We recorded the following median SUV in normal organs: heart, 1.82 (range, 0.78-4.11); liver, 1.35 (range, 0.72-2.99); bone marrow, 2.36 (range, 1.12-4.83); kidneys, 3.04 (range, 2.01-6.37); spleen, 5.79 (range, 2.07-10.5). No relevant associations between organ radiotracer uptake and MZL manifestation were observed, neither for SUV (ρ ≤ 0.21, P ≥ 0.07), SUV (ρ ≤ 0.20, P ≥ 0.09), LV (ρ ≤ 0.13, P ≥ 0.27), nor FLA (ρ ≤ 0.15, P ≥ 0.33).
Investigating a lymphoma-sink effect in patients with hematological neoplasms, we observed no relevant associations between lymphoma burden and uptake in normal organs. Those observations may have therapeutic implications, e.g., for "cold" SDF1-pathway disrupting or "hot," CXCR4-directed radiolabeled drugs, as with higher lymphoma load, normal organ uptake seems to remain stable.
最近研究实体瘤中的肿瘤库效应报告了肿瘤负荷较高的患者中正常器官摄取减少。然而，这种现象尚未应用于血液恶性肿瘤的治疗性放射性示踪剂。因此，我们旨在确定边缘区淋巴瘤（MZL）患者中潜在的“淋巴瘤库效应”，该效应通过 C-X-C 基序趋化因子受体（CXCR）4 定向 PET/CT 进行评估。
我们回顾性分析了 73 例接受 CXCR4 定向[Ga]Ga-PentixaFor PET/CT 的 MZL 患者。使用感兴趣区（VOI）定量正常未受影响器官摄取，并得出平均标准化摄取值（SUV）。还对 MZL 表现进行分割，以确定最大和峰值标准化摄取值 SUV（SUV）和体积参数，包括淋巴瘤体积（LV）和部分淋巴瘤活性（FLA，定义为淋巴瘤负荷的 LV*SUV）。这种方法总共捕获了 666 个 VOI，以捕获整个 MZL 表现负荷。我们使用 Spearman 秩相关来确定器官摄取与表达 CXCR4 的淋巴瘤病变之间的关联。
我们记录了正常器官的以下中位数 SUV：心脏，1.82（范围，0.78-4.11）；肝脏，1.35（范围，0.72-2.99）；骨髓，2.36（范围，1.12-4.83）；肾脏，3.04（范围，2.01-6.37）；脾脏，5.79（范围，2.07-10.5）。未观察到器官放射性示踪剂摄取与 MZL 表现之间存在相关关系，无论是 SUV（ρ≤0.21，P≥0.07）、SUV（ρ≤0.20，P≥0.09）、LV（ρ≤0.13，P≥0.27）还是 FLA（ρ≤0.15，P≥0.33）。
在研究血液恶性肿瘤中的淋巴瘤库效应时，我们观察到淋巴瘤负荷与正常器官摄取之间没有相关关系。这些观察结果可能具有治疗意义，例如对于 SDF1 途径的“冷”破坏或“热”、CXCR4 定向放射性标记药物，因为随着淋巴瘤负荷的增加，正常器官摄取似乎保持稳定。
