A case report of myeloid sarcoma of the gastrointestinal system

Myeloid sarcoma is a tumor mass of myeloblasts or immature myeloid cells occurring in an extramedullary site. The clinical presentation of myeloid sarcoma varies, and many organs or tissues can be involved. Myeloid sarcoma may be found in patients with acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), myeloproliferative neoplasm (MPN), or without any history. Morphologically, these cells may appear like myeloblasts, promyelocytes, or more mature granulocytes. Cytochemical and immunohistochemical stains are extremely important to make the right diagnosis. We report here a case of myeloid sarcoma in an unusual site in an 80-year-old male, without history of AML, MDS, or MPN. The patient presented with perigastric mass and numerous tumor nodules in the liver, mesentery, and omentum. His bone marrow was reactive, without evidence of AML, MDS, or MPN. The tumor masses were proven to be myeloid sarcoma by immunohistochemical stains (positive for CD34, CD68, and lysozyme) and cytogenetic studies.