Dexrazoxane: new indication. Anthracycline extravasation: continue using dimethyl sulfoxide

1) Anthracycline extravasation can provoke extensive tissue necrosis, sometimes with serious consequences. Topical dimethylsulfoxide (DMSO) is the main antidote known to prevent this necrosis. It is used off-licence in France, based on the results of non-comparative trials. Among nearly 150 patients treated with dimethylsulfoxide, only one required surgery and about 10% of patients had sequelae; 2) A product based on dexrazoxane, an iron chelator, also approved to prevent anthracycline cardiotoxicity, has now been authorized for intravenous treatment of anthracycline extravasation; 3) Clinical evaluation of dexrazoxane in this setting does not include any trials versus dimethylsulfoxide. The combination of dexrazoxane plus dimethylsulfoxide is contraindicated, based on the results of animal studies; 4) Clinical evaluation of dexrazoxane only includes one case of anthracycline extravasation from a central venous line; 5) In two non-comparative trials in a total of 54 patients, only one patient required surgery for tissue necrosis. About one-third of patients had local complications (sensory disorders, pain, cutaneous atrophy, or restricted movement); 6) The only known adverse effect of topical dimethylsulfoxide is local irritation. In contrast, 10% of patients who received intravenous dexrazoxane had an infection that the investigators considered possibly linked to dexrazoxane. In addition to the known haematological effects of dexrazoxane (leukopenia and thrombocytopenia), other serious adverse events observed in the two trials included a major increase in hepatic transaminase activity, elevated creatinine levels, and hyper- or hypokalaemia; 7) Based on an evaluation that is neither sufficiently thorough nor rigorous, the risk-benefit balance of intravenous dexrazoxane appears to be less favourable than that of local dimethylsulfoxide, which should therefore continue to be used in this setting. In the meantime, preventive measures should be strictly followed in order to prevent extravasation from occurring. The assessment of dexrazoxane in anthracycline extravasation from a central line also remains inadequate.