All of the following immunohistochemical markers are positive in the neoplastic cells of granulocytic sarcoma, except -
Granulocytic sarcoma (Chloroma or myeloblastoma)

Granulocytic sarcoma or chloroma is a solid tumor composed of myeloblasts.
A chloroma is an extramedullary manifestation of AML, i.e., it is a solid collection of leukemic cells occurring outside of the bone marrow.
These tumor often have a green tint due to the presence of myeloperoxidase.
Chloromas are more common in monocytic differentiation (M4 & M5 type) AML.
Though chloromas occur most commonly in patients with AML, they may also occur in a patient with : -


Myelodysplastic syndrome
Myeloproliferative syndromes → Myelofibrosis, CML, Polycythemia Vera, Essential thrombocytosis
Without concomitant disease, i.e., Primary chloroma.


Chloromas are positive for : -

CD 68            CD 20                    CD 117                                Lysozyme
CD 43            CD 34                    Myeloperoxidase
CD45RO
CD43
Myeloperoxidase
Lysozyme