Myeloid/natural killer cell precursor acute leukemia accompanied by homozygous protein C deficiency

Hematopoietic cell transplantation for myeloid/NK cell precursor acute leukemia in second remission

Myeloid/natural killer cell precursor acute leukemia (MNKPL) is a rare leukemia subtype characterized by a high incidence of extramedullary infiltration. No appropriate treatment strategy has so far been developed. Acute myelogenous leukemia-type chemotherapy combined with L-Asparaginase is an effective treatment for MNKPL. Hematopoietic cell transplantation is a second option in refractory cases.

Myeloid/natural killer cell precursor acute leukemia with multiple subcutaneous nodules as the initial presentation: a case report and literature review

Myeloid/natural killer (NK) cell precursor acute leukemia is a rare neoplasm, which is characterized by high incidence of extramedullary infiltration, especially in the mediastinum and lymph nodes, an aggressive course and poor prognosis. As coexpressing myeloid and NK-cell antigens, myeloid/NK-cell precursor acute leukemia (MNKL) may pose diagnostic difficulty. Because the developmental pathway of normal NK cells is not well understood, neoplams of NK-cell origin are not clearly identified. To our knowledge, there have been only about 30 cases with this disease published previously. In the current paper, we present a case of a 21-year-old male patient whose initial presentation showed numerous subcutaneous nodules without bone marrow involvement. A diagnosis of MNKL was finally made by skin biopsy, bone marrow immunohistochemistry and immunophenotypic analysis. Although bone marrow achieved complete remission using DA chemotherapeutic regimen, the skin nodules did not regress. However, FLAG chemotherapeutic regimen, including fludarabine, cytarabine and G-CSF, was effective for both bone marrow and skin involvement. To the best of our knowledge, this study is the first to describe the effect of FLAG regimen for the treatment of this disease, indicating that it may be effective against the skin involvement of MNKL.

Acute myeloblastic leukemia in a patient with hereditary protein C deficiency

The patient had been diagnosed with hereditary protein C deficiency. She recently developed acute myeloblastic leukemia (AML). Chemotherapy for AML by cytosine arabinoside, aclarubicin followed by granulocyte colony-stimulating factor (CAG) was started. Disseminated intravascular coagulation (DIC) was observed, however thromboembolic complication was not observed during the hospital course. Hematological remission was not obtained, and the patient died of pseudomembranous pancolitis. Whether the development of these rare disorders of hereditary protein C and AML are coincidental, or involve a causal relationship remains unknown.