Two consecutive spontaneous regressions to chronic phase in a patient with blastic transformation of chronic myelogenous leukemia.

In this report, we present a patient with chronic myeloid leukemia (CML) in blastic phase who had two consecutive episodes of spontaneous regression back to chronic phase without chemotherapy. Although, spontaneous remission (SR) is well documented in acute leukemia, SR in CML blastic phase is extremely rare and to the best of our knowledge only one case has been reported in the world literature. The factors possibly related to this phenomenon are discussed.