Cyclic oscillations of leucocyte counts in chronic myeloid leukaemia.

A patient with chronic myeloid leukaemia, having two unusual features, is described. He had absence of splenomegaly and marked periodic fluctuations of leucocyte counts, occurring spontaneously, in the initial phase of the disease. The latter finding suggests that, at least in some patients with chronic myeloid leukaemia, negative feed back control mechanism(s), possibly exerted by colony stimulating factor, may be retained which may have therapeutic implications.