Senay Mutaf, Zeynep Güral, Ant Uzay, Çağla Şafak Karaoğlan Yıldırım, Fulya Ağaoğlu
Acta Haematologica Oncologica Turcica - 2025;58(3):251-255
Myeloid sarcoma (MS) is a rare hematologic malignancy characterized by the uncontrolled proliferation of immature granulocytic cells in extramedullary tissues. It may occur de novo, represent an extramedullary manifestation of acute myeloid leukemia (AML), or develop following hematopoietic stem cell transplantation. In the literature, it is also referred to as granulocytic sarcoma, chloroma, or extramedullary myeloid tumor. The reported incidence of isolated de novo MS is approximately 2 per 100,000 in adults and 0.7 per 1,000,000 in children. When presenting concurrently with AML, the frequency ranges between 2-9% in adults and 10.9-23.3% in pediatric patients. In the post-transplant remission setting, its incidence has been reported between 5% and 12%. MS most commonly involves the skin, lymph nodes, soft tissues, and bones, while central nervous system (CNS) localization is exceedingly rare and typically does not cause parenchymal damage. Ostgaard et al. [1] found that MS was located in the craniospinal system in only 0.4% of AML patients. Pituitary involvement represents only a very small fraction of CNS cases, with fewer than 10 cases of pituitary or sellar region MS described in the literature to date (10, 12, 20). In this report, we present a rare case of pituitary relapse of MS occurring after allogeneic hematopoietic stem cell transplantation in a female patient with AML and discuss its diagnostic and therapeutic aspects in the context of current literature.
