A question of conscience

SIR,-Four of the 90 patients with sarcoma of the buttock whose drug histories were available for study had received intramuscular injections into the buttock. This could, of course, be a coincidence. There are no controls and no estimates for the use of iron by this route. I pointed out that the incidence of the association between intramuscular iron and sarcoma cannot be measured. The Rev Dr Metcalfe implies, quite rightly, that intramuscular iron is injected into the buttock and nowhere else. If there is a relationship between these injections and sarcoma we must suppose that the "observed" rate of iron use in this group of patients (more than 4",,) does not differ from the "expected" rate of use in the general population and we would have to consider the possibility that as many as 2 million patients in the United Kingdom have, at one time or another, received a course of iron injections into the buttock. This seems unlikely. In spite of the small numbers of patients studied, it was considered that a short report on them might bring other cases to light. I appreciate the Rev Dr Metcalfe's concern about the risk of causing anxiety among patients who have been treated in this way. This possibility is always considered very carefully before any publication of this type is contemplated. If, however, other cases of sarcoma related tc intramuscular iron do emerge as a result of this publication the case against intramuscular iron will be strengthened and many patients could be spared an unpleasant and almost invariably fatal illness.