Granulocytic sarcoma is an uncommon
tumor composed of granulocytic precursor cells. Because it occurs in a variety of clinical settings and because the
tumor cells are primitive it is frequently unrecognized during life. This presentation details the authors' experience with 61 biopsy-proven
granulocytic sarcomas. The patient age range was from 2 to 81 years (mean 48 years). In eight patients the
tumors were multiple. Most common sites of involvement were bone, periosteum, soft tissue, lymph node and skin. Twenty-two
tumors occurred in 15 patients with no known disease, 26 occurred in 24 patients with a known
myeloproliferative disorder, and 13 occurred in 11 patients with proven
acute myeloid leukemia. Thirteen of the 15 patients with no known disease developed acute
leukemia in from one to 49 months after the biopsy of their
tumors (mean 10 months). Most
tumors occurring in patients with a known
myeloproliferative disorder were associated with
blast crisis. The authors' cases displayed a morphologic range from well-differentiated to those
tumors that displayed virtually no evidence of differentiation by conventional microscopy. It was therefore not surprising that most
tumors were originally diagnosed as
lymphoma. Chloro-
acetate esterase (CAE) stains were performed on 56
tumors and 47 were studied with antilysozyme immunoperoxidase technique. Fifty-six of the 57 specimens studied by either technique were positive. Antilysozyme immunoperoxidase stains were particularly useful in confirming the diagnosis.