[ Title ]
- Tumour targeting and radiation dose of radioimmunotherapy with
Y-90-rituximab in CD20+B-cell lymphoma as predicted by Zr-89-rituximab
immuno-PET: impact of preloading with unlabelled rituximab
[ Journal ]
- EUROPEAN JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING
[ Author ]
- Muylle, K
Flamen, P
Vugts, D
Guiot, T
Ghanem, G
Meuleman, N
Bourgeois, P
Vanderlinden, B
van Dongen, GAMS
Everaert, H
Vaes, M
Bron, D
[ Abstract ]
- Purpose To compare using immuno-PET/CT the distribution of
Zr-89-labelled rituximab without and with a preload of unlabelled
rituximab to assess the impact of preloading with unlabelled rituximab
on tumour targeting and radiation dose of subsequent radioimmunotherapy
with Y-90-labelled rituximab in CD20+ B-cell lymphoma.
Methods Five patients with CD20+ B-cell lymphoma and progressive disease
were prospectively enrolled. All patients underwent three study phases:
initial dosimetric phase with baseline Zr-89-rituximab PET/CT imaging
without a cold preload, followed 3 weeks later by a second dosimetric
phase with administration of a standard preload (250 mg/m(2)) of
unlabelled rituximab followed by injection of Zr-89-rituximab, and a
therapeutic phase 1 week later with administration of unlabelled
rituximab followed by Y-90-rituximab. PET/CT imaging and tracer uptake
by organs and lesions were assessed.
Results With a cold rituximab preload, the calculated whole-body dose of
Y-90-rituximab was similar (mean 0.87 mSv/MBq, range 0.82-0.99 mSv/MBq)
in all patients. Without a preload, an increase in whole-body dose of 59
% and 87 % was noted in two patients with preserved circulating CD20+ B
cells. This increase in radiation dose was primarily due to a 12.4-fold
to 15-fold higher dose to the spleen without a preload. No significant
change in whole-body dose was noted in the three other patients with
B-cell depletion. Without a preload, consistently higher tumour uptake
was noticed in patients with B-cell depletion.
Conclusion Administration of the standard preload of unlabelled
rituximab impairs radioconjugate tumour targeting in the majority of
patients eligible for radioimmunotherapy, that is patients previously
treated with rituximab-containing therapeutic regimens. This common
practice may need to be reconsidered and further evaluated as the
rationale for this high preload has its origin in the ""prerituximab
era"".
[ URL ]
- http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Alerting&SrcApp=Alerting&DestApp=WOS&DestLinkType=FullRecord;UT=WOS:000356809100016