Remission of chronic idiopathic myelofibrosis to busulfan treatment.

Three patients with chronic idiopathic myelofibrosis have responded to busulfan treatment with an excellent hematologic remission and reversal of myelofibrosis and myeloid metaplasia. Four months after busulfan therapy all three patients showed an improvement of hematocrit and hemoglobin and reduction of the number of leukoerythroblasts. Cellular bone marrow was re-established in two patients. A decrease of hepatomegaly and splenomegaly also occurred and was well correlated with the hematologic response. In one patient, when busulfan was discontinued for about 2 years after achieving an excellent remission, hematologic relapse was accompanied by increase of hepatomegaly and splenomegaly. When busulfan treatment was resumed, hematologic response and decrease of hepatomegaly and splenomegaly reoccurred. This observation has demonstrated the beneficial effect of busulfan in chronic idiopathic myelofibrosis; therefore, the role of busulfan in the management of this disease should be further investigated.