Busulfan (Myleran) for Myelocytic Leukemia

To the Editor:— In your issue of July 19 (193:255, 1965), there is a question in regard to the treatment of chronic myelocytic leukemia. This is answered by Dr. John W. Frost with the unequivocal statement that "Busulfan (Myleran) is the treatment of choice in chronic myelocytic leukemia." Although this may be true, I have seen no report of the results of treatment with Busulfan, which are comparable to the number of cases treated, or the results of treatment, reported as the result of treatment by means of x-ray or radioactive phosphorus. J. H. Lawrence reported on the latter in 1954; Osgood and associates reported on a comparison of x-ray treatment with that of irradiated phosphorus in 1955; also, a report of my treatment has appeared in a relatively small series, published both in Germany and America, in 1961. Until it has been demonstrated by adequate comparisons, it seems