Myeloid sarcoma. Light micrograph of a diffuse leukemic infiltrate in the dermis with sparing of the epidermis. Perivascular or periadnexal aggregation of tumour cells is common. Patients with acute myeloid leukaemia (AML) can have tissue infiltrates of leukemic cells in different sites. The most common sites of involvement include skin, mucus membranes, orbit, central nervous system, lymph nodes, bones, gonads, and parenchymal organs (breast, genitourinary tract, gastrointestinal tract, and gonads).