Myeloid Sarcoma : Cytogenetics
Myeloid sarcoma shows association with t(8;21)(q22;q22.1). About 25% of pediatric and about 10% of adult AML patients with this translocation develop myeloid sarcoma. In the pediatric group, the most commonly involved sites are head and neck region (orbit, skull, and CNS). In adults with this translocation, there is no predilection for head and neck region. Skin lesions in myeloid sarcoma (leukemia cutis) are associated with 11q23.3 translocations and abnormalities of chromosome 16 such as inv(16). The median age of the patient is 2.6 years. In some cases, inv(16) is associated with intestinal presentation and there are plasmacytoid monocyte clusters. The prognosis is poor. There is a rare subtype of congenital leukemia which presents with multiple skin lesions of myeloid sarcoma shortly after birth. In many cases, the disease is limited to skin and undergoes spontaneous remission within days. It is associated with t(8;16)(p11.2;q13.3) This image shows megakaryoblastic myeloid sarcoma presenting in the small intestine. Uniform cells with little cytoplasm form sheet-like growth effacing the normal architecture. The tumor cells were positive for CD34, CD43, myeloperoxidase, and CD61 by immunohistochemistry. Image courtesy of: The New York Pathological Society (@NYPathSociety); used with permission.