The authors report one case of granulocytic sarcoma infiltrating the larynx and cervical lymph nodes in a 50-year-old smoking patient. At the time of diagnosis there was no clinical and laboratory evidence of acute myeloid leukemia or chronic myeloproliferative disease. Four months after diagnosis, bone marrow morphology was consistent with chronic myeloid leukemia, accelerated phase. Cytogenetic abnormalities (Ph 1 chromosome, t(1; 12) (p36; p13), and trisomy of chromosome 20) were also found in hemopoetic cells. Granulocytic sarcoma preceding installation of chronic myeloid leukemia, as described here, seems to be a rare clinical event.1891084-6; discussion 1086-9