Miyazaki Kyle S, Kuang Yu, Kwee Sandi A
Oncology Research Department and Hamamatsu/Queen's PET Imaging Center, The Queen's Medical Center, 1301 Punchbowl St., Honolulu, HI 96813 USA.
Department of Medical Physics, School of Allied Health Sciences, University of Nevada Las Vegas, Las Vegas, NV USA.
Nucl Med Mol Imaging. 2015 Jun;49(2):160-4. doi: 10.1007/s13139-014-0314-0. Epub 2015 Jan 9.
Radium-223 dichloride is an alpha-emitting radiopharmaceutical shown to prolong survival in patients with castrate-resistant prostate cancer (CRPC) and symptomatic skeletal metastases. This report describes in two patients the acute changes in bone metastatic activity detected by F-18 choline PET/CT imaging midway during treatment with radium-223 dichloride. In addition to visual and standardized uptake value analysis, changes in the whole-body tumor burden were quantified by measuring the difference in net metabolically active tumor volume (MATV) and total lesion activity (TLA) between pre- and mid-treatment PET scans. After the third dose of radium-223 dichloride, near-total disappearance of abnormal skeletal activity was observed in one case (net MATV change from 260.7 to 0.8 cc; net TLA change from 510.7 to 2.1), while a heterogeneous tumor response was observed in the other (net MATV change from 272.2 to 241.3 cc; net TLA change from 987.1 to 779.4). Corresponding normalization and persistent elevation in serum alkaline phosphatase levels were observed in these cases, respectively. Further research is needed to determine the predictive value of serial F-18 choline PET/CT imaging in patients receiving radium-223 dichloride for CRPC.
二氯化镭-223是一种发射α粒子的放射性药物，已证明可延长去势抵抗性前列腺癌（CRPC）伴症状性骨转移患者的生存期。本报告描述了两例患者在接受二氯化镭-223治疗期间，通过F-18胆碱PET/CT成像检测到的骨转移活性的急性变化。除了视觉和标准化摄取值分析外，还通过测量治疗前和治疗中期PET扫描之间代谢活跃肿瘤净体积（MATV）和总病灶活性（TLA）的差异，对全身肿瘤负荷的变化进行了量化。在给予第三剂二氯化镭-223后，一例患者异常骨活性几乎完全消失（MATV净变化从260.7立方厘米降至0.8立方厘米；TLA净变化从510.7降至2.1），而另一例患者观察到异质性肿瘤反应（MATV净变化从272.2立方厘米降至241.3立方厘米；TLA净变化从987.1降至779.4）。在这些病例中，分别观察到血清碱性磷酸酶水平相应的正常化和持续升高。需要进一步研究以确定连续F-18胆碱PET/CT成像对接受二氯化镭-223治疗的CRPC患者的预测价值。
