Absract
Background: Myeloid sarcoma (MS), also known as granulocytic sarcoma or chloroma, is a rare extramedullary tumor consisting of myeloblasts or immature myeloid cells that disrupt the involved tissue and typically occurs concurrently with acute myeloid leukemia (AML). It can also occur in association with accelerated-phase chronic myeloid leukemia or myelodysplastic syndrome; as an extramedullary relapse of AML, including in the post-bone marrow transplant setting; and occasionally as the first presenting manifestation, even before bone marrow involvement. Bone, periosteum, skin, orbit, lymph nodes, the gastrointestinal tract, and the central nervous system are the most commonly involved sites in patients presenting with MS; however, skin and orbital localizations are the most often reported sites in children .
Case: We present a 2-year-old male patient who was referred to the pediatric hematology oncology clinic with left pariatotemporal mass. In computed tomography (CT) of brain; a mass lesion of approximately 8x9 cm in size extending from the left parietotemporal lobe to the inferior, extending towards the skin / subcutaneous, causing lytic changes in the left posterior temporal bone was observed. (figure 1a) . A neurosurgery consultation was planned. The brain antieudema protective treatment with prednisilone 40 mgr/kg first 3 days and subsuquent to 30 mgr/kg 4 days was initiated. Soft tissue tumor and the bone marrow metastasis or AML and granulocytic sarcoma were the initiall diagnositc features. Flowcytometric peripheral blood test was reported %8 myeloblast. In this period to decrease the WBC count: 76000 10’9/L to safe values cytosine arabinoside treatment of 100mg/m2 dosage for 24 hours was iniated. The control values in treatment hours and days are intable 1 . In the second day of follow ups, WBC count was 42000 10’9/L and bone marrow aspiration (BMA) and cerebrospinal fluid was planned. The flow cytometric evaulation of BMA showed %10 myelobalasts. The genetic panel for AML was sent form bone marrow aspirate. In the 3th day of treatment; the genetic tests reported t(8,21) positivity in this paitent. The AML diagnosis was comfirmed and AML BFM 2019 protocol was initiated to the patient. The involution of tumoral mass from first day and first month of CT and physical view are in figure 1a-b and 2a-b respectively.
Conclusion: The most common presentation sites in children with MS is skin and orbital localizations. Dexamethosene and conventianol chemathearphy is first steps in treatment. Our case presented exterior pariatotemporal mass extending to interior left pariatel lobe with extraordinary feature. This presentation may need differantial diagnosis even with brain tumors.
Keywords: Childhood, Acute myeloid lekeumia, Myeloid Sarcoma, Brain tumors