Myeloid sarcomas of the head and neck in pediatric patients with myeloid leukemia.

Myeloid sarcoma is a rare extramedullary tumor composed of malignant myeloid cells that occur in the presence of myeloid leukemia. We report a case series of pediatric head and neck myeloid sarcomas representative of the epidemiology, symptomatology, laboratorial correlations, prognoses, and treatment of extramedullary leukemia. Presented are 3 cases involving patients ranging from 17 months to 11 years of age. Two patients were successfully treated with chemotherapy, and in the third patient, a large lytic lesion was treated palliatively with proton beam therapy. Knowledge and recognition of myeloid sarcomas is important as they can be locally invasive, and they may also be used as a diagnostic tool or a prognostic indicator for leukemia.