The Effect of Ifosfamide on Tumor Oxygenation at Different Temperatures

A broad range of human tumors respond to the oxazaphosphorine compound ifosfamide (IFO), an analogue of the well-established alcylating agent cyclophosphamid (CP) [for review: 1]. IFO, like CP, may be regarded as a prodrug which undergoes a complex metabolism in vivo [2–4]. The initial metabolism of IFO consists of two different pathways: An enzymatic hydroxylation at carbon-4 forms 4-OH-IFO which is probably the major biologically active compound, and a side chain oxydation leading to the liberation of chloroacetaldehyde, a compound with possible neurotoxic properties.