本研究的目的是评估钆匹烯醇与钆苯酯二葡胺对比增强磁共振成像 (MRI) 对全脑放疗 (WBRT) 和立体定向放射外科 (SRS) 治疗脑转移瘤 (BM) 决策的影响在 MRI 造影剂钆匹烯醇和钆苯酯二葡胺（均以 0.1 mmol/kg 给药）之间的双盲交叉 IIb 期比较研究中，患有 BM 的患者接受了 2 次单独的 MRI 检查。使用相同 MRI 扫描仪和协议的单个部位的成像数据包含在该事后分析中。在任何两个 MRI 中具有 1 个或多个 BM 的患者均接受靶区描绘以制定治疗计划。两名放射肿瘤学家绘制了所有可见病灶的轮廓，并根据转移灶的数量决定采用 SRS 或 WBRT。对于每位患者，计算了两个 MRI 的 SRS 或 WBRT 治疗计划，并将总靶区 (GTV) 视为肿瘤的对比度增强方面。获得了暴露于 12 Gy (V12) 的健康大脑的平均 GTV 和体积，以及 Dice 相似系数得分。另外还计算了斯皮尔曼等级 (ρ) 相关性以评估线性差异。三位不同的放射肿瘤专家对用于勾画轮廓的对比增强进行盲目评价。其中包括 13 名成年患者。与钆贝酯二葡胺相比，钆匹烯醇在 7 名患者 (54%) 中表现出更多的 BM。在两个 MRI 组中总共 63 个已识别的转移性病灶中，可以定义 3 个亚组：A，48 个（24 对）在两种模式中均检测到相同的 GTV； B，仅在钆匹烯醇组中可见 13 个 GTV（平均值 ± SD，0.16 ± 0.37 cm3）；和 C，2 个 GTV 仅在钆苯酯二葡胺组中可见（平均值 ± SD，0.01 ± 0.01）。 2 名 (15%) 患者的治疗指征发生变化，其中 1 名患者从不接受治疗更改为 SRS，1 名患者从 SRS 更改为 WBRT。两种药物的平均 GTV 和脑 V12 相当（P = 0.694，P = 0.974）。平均 Dice 相似系数为 0.70 ± 0.14 (ρ = 0.82)。据读者称，使用钆匹烯醇的病例（36 项评估中的 23 项）改善了 63.9% 的靶区定义，使用钆贝酸二葡胺（36 项评估中的 8 项）改善了 22.2% 的病例，而 13.9% 的病例（36 项评估中的 5 项）获得了等效性。增强 MRI 改善了 BM 检测和表征，直接影响 WBRT 和 SRS 之间的放射治疗决策。此外，可以使用钆匹烯醇进行更精确的目标描绘和规划。需要对更大的患者群体进行前瞻性评估来证实这些发现。版权所有 © 2024 作者。由 Wolters Kluwer Health, Inc. 出版

The aim of this study was to assess the effect of gadopiclenol versus gadobenate dimeglumine contrast-enhanced magnetic resonance imaging (MRI) on decision-making between whole-brain radiotherapy (WBRT) and stereotactic radiosurgery (SRS) for treatment of brain metastases (BMs).Patients with BMs underwent 2 separate MRI examinations in a double-blind crossover phase IIb comparative study between the MRI contrast agents gadopiclenol and gadobenate dimeglumine, both administered at 0.1 mmol/kg. The imaging data of a single site using identical MRI scanners and protocols were included in this post hoc analysis. Patients with 1 or more BMs in any of both MRIs were subjected to target volume delineation for treatment planning. Two radiation oncologists contoured all visible lesions and decided upon SRS or WBRT, according to the number of metastases. For each patient, SRS or WBRT treatment plans were calculated for both MRIs, considering the gross target volume (GTV) as the contrast-enhancing aspects of the tumor. Mean GTVs and volume of healthy brain exposed to 12 Gy (V12), as well as Dice similarity coefficient scores, were obtained. The Spearman rank (ρ) correlation was additionally calculated for assessing linear differences. Three different expert radiation oncologists blindly rated the contrast enhancement for contouring purposes.Thirteen adult patients were included. Gadopiclenol depicted additional BM as compared with gadobenate dimeglumine in 7 patients (54%). Of a total of 63 identified metastatic lesions in both MRI sets, 3 subgroups could be defined: A, 48 (24 pairs) detected equal GTVs visible in both modalities; B, 13 GTVs only visible in the gadopiclenol set (mean ± SD, 0.16 ± 0.37 cm3); and C, 2 GTVs only visible in the gadobenate dimeglumine set (mean ± SD, 0.01 ± 0.01). Treatment indication was changed for 2 (15%) patients, 1 from no treatment to SRS and for 1 from SRS to WBRT. The mean GTVs and brain V12 were comparable between both agents (P = 0.694, P = 0.974). The mean Dice similarity coefficient was 0.70 ± 0.14 (ρ = 0.82). According to the readers, target volume definition was improved in 63.9% of cases (23 of 36 evaluations) with gadopiclenol and 22.2% with gadobenate dimeglumine (8 of 36), whereas equivalence was obtained in 13.9% (5 of 36).Gadopiclenol-enhanced MRI improved BM detection and characterization, with a direct impact on radiotherapy treatment decision between WBRT and SRS. Additionally, a more exact target delineation and planning could be performed with gadopiclenol. A prospective evaluation in a larger cohort of patients is required to confirm these findings.Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.