[Recurrent lymphoblastic crises sensitive to vincristine in a case of chronic myeloid leukemia].

Approximately one year after the onset of chronic myeloid leukemia, a 66-year-old patient had multiple recurrent blast crises with the morphological, cytochemical, and immunological features of lymphoblasts. The lymphoblastic eruptions proved always highly sensitive to small doses of vincristine only (1.5 mg), which at variable intervals, of at first 3 months and later 20 days, brought about the immediate disappearance of blast cells from the peripheral circulation as well as from bone marrow blood. Some variable clinical aspects of the case during the crises are described; the crises recurred until the patient's sudden death due to cardiac causes.