Potential and pitfalls of 89Zr-immuno-PET to assess target status: 89Zr-trastuzumab as an example.
EJNMMI Res
; 11(1): 74, 2021 Aug 21.
Article
em En
| MEDLINE
| ID: mdl-34417917
ABSTRACT
BACKGROUND:
89Zirconium-immuno-positron emission tomography (89Zr-immuno-PET) is used for assessment of target status to guide antibody-based therapy. We aim to determine the relation between antibody tumor uptake and target concentration to improve future study design and interpretation.METHODS:
The relation between tumor uptake and target concentration was predicted by mathematical modeling of 89Zr-labeled antibody disposition in the tumor. Literature values for trastuzumab kinetics were used to provide an example.RESULTS:
89Zr-trastuzumab uptake initially increases with increasing target concentration, until it levels off to a constant value. This is determined by the total administered mass dose of trastuzumab. For a commonly used imaging dose of 50 mg 89Zr-trastuzumab, uptake can discriminate between immunohistochemistry score (IHC) 0 versus 1-2-3.CONCLUSION:
The example for 89Zr-trastuzumab illustrates the potential to assess target expression. The pitfall of false-positive findings depends on the cut-off to define clinical target positivity (i.e., IHC 3) and the administered mass dose.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
EJNMMI Res
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Holanda