Granulocytic sarcoma

A myeloid sarcoma (chloroma, granulocytic sarcoma, extramedullary myeloid tumor), is a solid tumor composed of immature white blood cells called myeloblasts. A chloroma is an extramedullary manifestation of acute myeloid leukemia; in other words, it is a solid collection of leukemic cells occurring outside of the bone marrow. [Source: Wikipedia ]