RT Journal Article
SR Electronic
T1 First-in-Humans Application of <sup>161</sup>Tb: A Feasibility Study Using <sup>161</sup>Tb-DOTATOC
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1391
OP 1397
DO 10.2967/jnumed.120.258376
VO 62
IS 10
A1 Baum, Richard P.
A1 Singh, Aviral
A1 Kulkarni, Harshad R.
A1 Bernhardt, Peter
A1 Rydén, Tobias
A1 Schuchardt, Christiane
A1 Gracheva, Nadezda
A1 Grundler, Pascal V.
A1 Köster, Ulli
A1 Müller, Dirk
A1 Pröhl, Michael
A1 Zeevaart, Jan Rijn
A1 Schibli, Roger
A1 van der Meulen, Nicholas P.
A1 Müller, Cristina
YR 2021
UL http://jnm.snmjournals.org/content/62/10/1391.abstract
AB 161Tb has decay properties similar to those of 177Lu but, additionally, emits a substantial number of conversion and Auger electrons. The aim of this study was to apply 161Tb in a clinical setting and to investigate the feasibility of visualizing the physiologic and tumor biodistributions of 161Tb-DOTATOC. Methods: 161Tb was shipped from Paul Scherrer Institute, Villigen-PSI, Switzerland, to Zentralklinik Bad Berka, Bad Berka, Germany, where it was used for the radiolabeling of DOTATOC. In 2 separate studies, 596 and 1,300 MBq of 161Tb-DOTATOC were administered to a 35-y-old male patient with a metastatic, well-differentiated, nonfunctional malignant paraganglioma and a 70-y-old male patient with a metastatic, functional neuroendocrine neoplasm of the pancreatic tail, respectively. Whole-body planar γ-scintigraphy images were acquired over a period of several days for dosimetry calculations. SPECT/CT images were reconstructed using a recently established protocol and visually analyzed. Patients were observed for adverse events after the application of 161Tb-DOTATOC. Results: The radiolabeling of DOTATOC with 161Tb was readily achieved with a high radiochemical purity suitable for patient application. Planar images and dosimetry provided the expected time-dependent biodistribution of 161Tb-DOTATOC in the liver, kidneys, spleen, and urinary bladder. SPECT/CT images were of high quality and visualized even small metastases in bones and liver. The application of 161Tb-DOTATOC was well tolerated, and no related adverse events were reported. Conclusion: This study demonstrated the feasibility of imaging even small metastases after the injection of relatively low activities of 161Tb-DOTATOC using γ-scintigraphy and SPECT/CT. On the basis of this essential first step in translating 161Tb to clinics, further efforts will be directed toward the application of 161Tb for therapeutic purposes.