Francesco Turturro

85 AN UNUSUAL CASE OF GRANULOCYTIC SARCOMAS.

Introduction Granulocytic sarcomas (GSs), or extramedullary collections of immature leukemic cells, are observed in only 3-7% of myeloid leukemias. The t(8;21) occurs in about 7% of patients with acute myeloid leukemia (AML) and in about 18% of leukemias classified as M2. This translocation seems to have a higher association with GS. GSs most frequently arise adjacent to bony or neural structures and rarely involve more than 2 sites. Though patients with t(8;21) generally have a more favorable prognosis, the presence of these sarcomas makes their course less favorable. We report a case of a woman with AML M2 who presented with 5 sites of extramedullary involvement, including pleural fluid involvement, which is exceedingly rare. Case Report A 24-year-old female presented with weakness and shortness of breath of 1 months duration. She was initially evaluated and treated for an upper respiratory tract infection. Her symptoms persisted. Further work-up at a local hospital revealed the presence of circulating blasts on peripheral blood smear (PBS). Physical exam was positive for a left eye ptosis and bruising present on extremities. Labs at that time showed a WBC count of 22,500, hemoglobin of 7.0, and platelet count of 42,000 with 58% blasts seen on the PBS. The patient was transferred to our tertiary care center where a bone marrow biopsy and aspirate were done. There was 100% cellularity with blast forms comprising > 80% of those cells. Findings were morphologically consistent with AML M2. Cytogenetic analysis showed a 46,XX,t(8;21)(q22;q22). A CT scan of the chest and abdomen were done, which showed a paratracheal mass, an anterior mediastinal mass, a perinephric soft tissue density, as well as the development of a new pleural effusion. A superior extraconal mass was found in the left orbit on MRI. The pleural effusion was evaluated by thoracentesis and positive for malignant cells by cytology. FISH analysis was performed on those cells and confirmed the presence of the t(8;21). CSF was negative for the presence of malignant cells. The patient received chemotherapy with cytarabine and an anthracycline together for induction with a dose of prophylactic intrathecal methotrexate at the time of diagnostic lumbar puncture. Following induction therapy repeat scans have shown a resolution of the pleural effusion and improvement in the size of the other GSs. Conclusion GSs, though uncommon, are more frequently seen with t(8;21) in AML and can present with multiple sites of extramedullary involvement, including the pleural space. Proper identification of these lesions is important for therapeutic and prognostic implications.