Use and risks of phosphorus-32 in the treatment of polycythaemia vera.

The risk of development of cancer, and more specifically acute leukaemia, after use of phosphorus-32 in patients with polycythaemia vera has been recognised for approximately 40 years. As a consequence of this risk, the indications for, and contraindications to, 32P are unclear in the physician's mind. This paper aims to clarify the problem. The relation between polycythaemia vera and leukaemia is explored and the question of whether chemotherapy represents an alternative to 32P is discussed. From the results obtained to date, two clear conclusions can be drawn: First, whatever the age of the patient, phlebotomy must be used to avoid the menace of vascular complications before the institution of basic treatment, but it cannot be used as the sole form of treatment. Second, 32P treatment retains an important role at least when chemotherapy fails and in elderly patients (>70 years).