NUCLEAR MEDICINE APPLICATIONS FOR BONE METASTASES 

The Quarterly Journal of Nuclear Medicine 2001 March;45(1):91-9

Copyright © 2009 EDIZIONI MINERVA MEDICA

lingua: Inglese

Systemic metabolic radiotherapy with samarium-153 EDTMP for the treatment of painful bone metastasis

Serafini A. N.

From the Division of Nuclear Medicine University of Miami School of Medicine, Miami, Florida, USA

Various radio­iso­topes con­ju­gat­ed to pyro­sphos­phate ana­logues ­have ­been devel­oped for system­ic meta­bol­ic radio­ther­a­py. Samarium-153-­EDTMP is a 1:1 com­plex of radio­ac­tive Samarium-153 and a Tetraphosphonate [eth­y­len­e­di­a­mine-tet­ra­meth­yl­ene phos­phon­ic ­acid (­EDTMP)]. Samarium Sm-153-­EDTMP has a ­high affin­ity for skel­e­tal tis­sue and con­cen­trates by chem­iab­sorp­tion in are­as of ­enhanced meta­bol­ic activ­ity, ­where it asso­ciates ­with the hydrox­yap­pe­tite crys­tal. Samarium-153 Lexidronam [Quadramet (R)] has ­been ­approved for rou­tine use by the FDA. This ­agent ­offers sev­er­al advan­tag­es ­over oth­er ­agents ­used for pal­li­at­ing ­bone ­pain. Due to its ­half-­life of 46 ­hours and its ­beta emis­sions, a ­high ­dose ­rate can be deliv­ered to ­regions adja­cent to ­enhanced oste­o­blas­tic activ­ity ­over a ­short peri­od of ­time ­with lit­tle resid­u­al ­long ­term activ­ity ­being ­left in the ­bone mar­row. This ­paper sum­mariz­es ­both ani­mal stud­ies and clin­i­cal stud­ies per­formed ­with ­this ­agent. Special empha­sis ­will be giv­en to the piv­ot­al Phase-III clin­i­cal stud­ies and sub­se­quent stud­ies per­formed ­since its approv­al by the FDA. Special con­sid­er­a­tions regard­ing appro­pri­ate selec­tion of ­patients, prep­ar­a­tion, fol­low-up of ­patients and adjust­ments to the usu­al rec­om­mend­ed ­dose [1 mCi/kg (35 Mbq/kg)] ­will be dis­cussed. Current and ­future treat­ment ­options uti­liz­ing Sm-153-­EDTMP ­with oth­er phar­ma­ceu­ti­cals ­appear prom­is­ing and ­will sub­stan­tial­ly ­extend its use ­into new are­as. In addi­tion, ­because it ­also ­emits a 103 keV gam­ma ray ­which ­makes it suit­able for imag­ing and assess­ment of bio­dis­trib­u­tion, dos­i­met­ric appli­ca­tions are pos­sible in the ­future.