123 i-mibg for detection of subacute doxorubicin-induced cardiotoxicity in patients with malignant lymphoma

Doxorubicin is the mainstay of curative lymphoma treatment but is associated with a dose-dependent cardiotoxicity that is often recognized too late to avoid substantial irreversible cardiac injury. iodine-123 metaiodobenzylguanidine (123i-mibg) is a gamma-emitting tracer that mimics noradrenaline uptake, storage, and release mechanisms in adrenergic presynaptic neurons. 123i-mibg scintigraphy can be used for assessment of doxorubicin-induced injury to myocardial adrenergic neurons during treatment and could be the tool for early detection of doxorubicin cardiotoxicity, which is currently lacking. a total of 37 lymphoma patients scheduled for doxorubicin treatment were included in our study. 123i-mibg imaging was performed prior to chemotherapy and after a median of 4 cycles of doxorubicin. early and late heart-to-mediastinum ratios (h/mearly and h/mlate) and washout rate (wor) were used for evaluation of cardiotoxicity. the prognostic value of 123i-mibg results was assessed using left ventricular ejection fraction (lvef) as measured by cardiac magnetic resonance at 1-year follow-up. we found a post-therapy increase in wor (including nine patients with > 10% increase), which was not statistically significant (18.6 vs 23.4%, p = 0.09). the difference appeared to be driven by an increase in h/mearly. lvef decreased from baseline to 1-year follow-up (64 vs 58%, p = 0.03). lvef change was not associated with changes in wor (p = 0.5). the present study does not provide evidence for 123i-mibg imaging as a clinically applicable tool for early detection of doxorubicin-induced cardiotoxicity.