Imidlertid er razoxan (den racemiske blanding af dexrazoxan og levrazoxan) rapporteret til at være forbundet med udviklingen af sekundære maligniteter hos mus (lymfoide neoplasmer) og rotter (svulst i uterus) efter indgivelse over en længere periode.
The carcinogenic potential of dexrazoxane has not been investigated, however, razoxane, (the racemic mixture of dexrazoxane and levrazoxane), has been reported to be associated with the development of secondary malignancies in mice (lymphoid neoplasms) and rats (uterine carcinomas) after administration for a prolonged period of time.