[Myeloid/natural killer cell acute leukemia resembling acute promyelocytic leukemia]

In order to improve the recognition of myeloid/natural killer cell acute leukemia and to reduce misdiagnosis, one case of myeloid/natural killer cell acute leukemia resembling acute promyelocytic leukemia(APL) was reported and the related articles published were reviewed. A series of clinical tests, the morphologic and immunophenotypic analysis of leukemia cells, cytogenetic and molecular biological examinations were performed. The results indicated that the patient had anemia, thrombocytopenia and leucocytosis, but no evidence of lymphadenopathy and hepatosplenomegaly. The morphology of leukemia cells was similar to that of abnormal promyelocytic cells, especially the variant of M3 (M3v) leukemia cells. The leukemia cells expressed CD117, CD33, CD15, CD56 and cMPO, but did not express CD34, HLA-DR, CD13 and CD16. Abnormal cytogenetics with del (7) (q22q32) was found. Neither t(15;17) nor PML/RARα gene rearrangement was detected. The patient failed to show a differentiation-induction response to all-trans retinoic acid(ATRA). In conclusion, the myeloid/natural killer cell leukemia is extremely rare. It is very important to distinguish the disorder from APL/M3v. The patient with myeloid/natural kill cell acute leukemia should be treated with chemotherapy as acute myeloid leukemia.