Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York.
Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York.
J Vasc Interv Radiol. 2023 Sep;34(9):1556-1564.e4. doi: 10.1016/j.jvir.2023.05.022. Epub 2023 May 16.
To evaluate the yttrium-90 (Y) activity distribution in biopsy tissue samples of the treated liver to quantify the dose with higher spatial resolution than positron emission tomography (PET) for accurate investigation of correlations with microscopic biological effects and to evaluate the radiation safety of this procedure.
Eighty-six core biopsy specimens were obtained from 18 colorectal liver metastases (CLMs) immediately after Y transarterial radioembolization (TARE) with either resin or glass microspheres using real-time Y PET/CT guidance in 17 patients. A high-resolution micro-computed tomography (micro-CT) scanner was used to image the microspheres in part of the specimens and allow quantification of Y activity directly or by calibrating autoradiography (ARG) images. The mean doses to the specimens were derived from the measured specimens' activity concentrations and from the PET/CT scan at the location of the biopsy needle tip for all cases. Staff exposures were monitored.
The mean measured Y activity concentration in the CLM specimens at time of infusion was 2.4 ± 4.0 MBq/mL. The biopsies revealed higher activity heterogeneity than PET. Radiation exposure to the interventional radiologists during post-TARE biopsy procedures was minimal.
Counting the microspheres and measuring the activity in biopsy specimens obtained after TARE are safe and feasible and can be used to determine the administered activity and its distribution in the treated and biopsied liver tissue with high spatial resolution. Complementing Y PET/CT imaging with this approach promises to yield more accurate direct correlation of histopathological changes and absorbed dose in the examined specimens.
评估经动脉放射性栓塞术（TARE）治疗后的肝组织活检样本中的钇-90（Y）活性分布，以比正电子发射断层扫描（PET）更高的空间分辨率量化剂量，从而准确研究与微观生物学效应的相关性，并评估该程序的辐射安全性。
在 17 名患者中，使用实时 Y 放射性核素 PET/CT 引导，对 18 个结直肠癌肝转移瘤（CLM）的 86 个核心活检样本进行 Y 放射性核素树脂或玻璃微球 TARE 治疗后立即取样。使用高分辨率微计算机断层扫描（micro-CT）扫描仪对部分样本中的微球进行成像，并允许通过直接量化 Y 活性或校准放射自显影（ARG）图像进行定量。对于所有病例，通过测量样本的活性浓度和活检针尖端位置的 PET/CT 扫描，得出样本的平均剂量。监测工作人员的暴露情况。
输注时 CLM 样本中的平均测量 Y 活性浓度为 2.4±4.0 MBq/mL。活检显示出比 PET 更高的活性异质性。TARE 后活检过程中对介入放射科医生的辐射暴露极小。
在 TARE 后获取的微球计数和活检样本活性测量是安全可行的，可以用于确定放射性核素在治疗和活检肝组织中的给药活性及其分布，具有高空间分辨率。通过这种方法补充 Y PET/CT 成像有望更准确地直接关联检查样本中的组织病理学变化和吸收剂量。
