Isolated myeloid sarcoma with pericardial and pleural effusions as first manifestation: A case report

Rationale: Myeloid sarcoma (MS) involves the proliferation of extramedullary blasts from 1 or more myeloid lineages, replacing the original tissue structures, and these neoplasias are called granulocytic sarcoma, chloroma, or extramedullary myeloid neoplasms. These tumors develop in lymphoid organs, bones, skin, soft tissues, various mucous membranes, organs, and the central nervous system. MS is rare in non-leukemic patients, while MS patient with effusion as the first manifestation is even rare. Patient concerns: We report the case of 44-year-old woman with abdominal pain, diarrhea, and vomiting. Diagnosis: Ultrasound examination and computed tomography of the chest revealed large pericardial effusions and bilateral pleural effusions. Cytomorphological examination of the pericardial and pleural effusion, flow cytometry, and immunohistochemical markers suggested myeloid tumor cells. However, concurrent peripheral blood and bone marrow examinations showed no evidence of acute myeloid leukemia. The patient was eventually diagnosed with isolated MS. Interventions and outcomes: After chemotherapy with pirarubicin + cytarabine and high-dose cytarabine + etoposide, the pericardial effusion and pleural effusion were absorbed, and the mediastinal mass significantly shrunk. One year after patient gave up treatment, acute myeloid leukemia (AML) was confirmed by bone marrow examinations. Conclusion: The early manifestations of the patient lacked specificity and were highly susceptible to misdiagnosis. Cytomorphology and flow cytology indicated important directions for the diagnosis of the disease in the early stage. Administration of chemotherapy regimen containing cytarabine could prolong disease-free survival and time before progress to AML.