Granulocytic sarcoma (GS) is an extramedullary tumor composed of immature myeloid cells. The objectives of this study were to describe the frequency, presenting characteristics, and survival in patients with nonleukemic GS by conducting a review of all untreated patients presenting to the MD Anderson Cancer Center between January 1990 and June 2002. In all, 21 patients with nonleukemic GS, 1520 patients with acute myeloid leukemia (AML), and 402 patients with high-risk myelodysplastic syndrome (MDS) were identified. GS occurred in 1.4% of patients with AML, and 1.1% of patients with AML or high-risk MDSs. The median patient age was 57 years (range, 7-81). Among 20 patients with available cytogenetics in tissue and/or bone marrow, six had chromosome 8 abnormalities. The median follow-up of surviving patients is 12 months (range, 7-75). In all, 20 patients were treated. Patients were treated with AML-type chemotherapy (n=16), chemotherapy and radiotherapy (n=3), or radiotherapy alone (n=1). A total of 13 patients (65%) achieved complete remission and one patient (5%) achieved partial remission. The median overall survival was 20 months (range, 1-75), median overall failure-free survival was 12 months (range, 1-75). The median survival of patients with chromosome 8 abnormalities was 12 months compared with 40 months of those without (P=0.17). Novel therapies for patients with GS are required.