Effect of tamoxifen in an experimental model of breast tumor studied by dynamic contrast-enhanced magnetic resonance imaging and different contrast agents.
OBJECTIVE
The aim of this study was to compare the efficacy of gadoteridol, B22956/1 (a new protein binding blood pool contrast agent), and (Gd-DTPA)37-albumin in detecting, by dynamic contrast-enhanced magnetic resonance imaging (MRI), the effect in vivo of tamoxifen in an experimental model of breast tumor implanted in rats.


METHODS
Tumors were induced by subcutaneous injection of 10 mammary adenocarcinoma cells (13762 MAT B III). Treatment with tamoxifen (or vehicle) started on day 4 after implantation. On day 10 after implantation, animals were observed by MRI using B22956/1 (or gadoteridol) and, 24 hours later, using (Gd-DTPA)37-albumin.


RESULTS
Dynamic contrast-enhanced magnetic resonance imaging data showed that tamoxifen treatment decreased vascular permeability to B22956/1, whereas no difference was detectable in permeability to gadoteridol or to (Gd-DTPA)37-albumin. No effect on fractional plasma volume was detected with either of contrast agents.


CONCLUSIONS
B22956/1 is superior to both small Gd chelates and macromolecular contrast agents in the assessment of the effect of tamoxifen treatment on tumor vasculature.
Marzola
Pasquina
P
Dipartimento di Scienze Morfologico-Biomediche, Sezione di Anatomia ed Istologia, Università di Verona, Verona. pasquina.marzola@univr.it
Ramponi
Simona
S
Nicolato
Elena
E
Lovati
Emanuela
E
Sandri
Marco
M
Calderan
Laura
L
Crescimanno
Caterina
C
Merigo
Flavia
F
Sbarbati
Andrea
A
Grotti
Adriana
A
Vultaggio
Stefania
S
Cavagna
Friederich
F
Lorusso
Vito
V
Osculati
Francesco
F
D000418:Albumins; D020533:Angiogenesis Inhibitors / Q000494:pharmacology*; D000818:Animals; D001943:Breast Neoplasms / Q000098:blood supply / Q000188:drug therapy*; D003287:Contrast Media; D004965:Estrogen Antagonists / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D005682:Gadolinium; D019786:Gadolinium DTPA; D006571:Heterocyclic Compounds; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008325:Mammary Neoplasms, Experimental; D009942:Organometallic Compounds; D051381:Rats; D013629:Tamoxifen / Q000494:pharmacology* / Q000627:therapeutic use
D000418:Albumins; D020533:Angiogenesis Inhibitors; D003287:Contrast Media; D004965:Estrogen Antagonists; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C062402:gadoteridol; D013629:Tamoxifen; D005682:Gadolinium; D019786:Gadolinium DTPA