An 87-yr-old woman was diagnosed with AML with myelodysplasia-related changes (AML-MRC). The initial complete blood count showed Hb level of 5.9 g/dL, platelet counts of 27x10(9)/L, and white blood cell counts of 85.33x10(9)/L with 55% blasts. Peripheral blood samples were used in all the tests, as bone marrow examination could not be performed because of the patient's extremely advanced age and poor general health condition. Flow cytometric analysis, chromosome analysis, FISH, and reverse transcriptase-PCR (RT-PCR) results indicated AML-MRC resulting from t(3;21) with the RUNX1-MECOM fusion gene. To our knowledge, this is the second most elderly de novo AML patient associated with t(3;21) to be reported.
Aged, 80 and over ; Blood Cells/pathology ; Chromosomes, Human, Pair 21 ; Chromosomes, Human, Pair 3 ; Female ; Humans ; Karyotyping ; Leukemia, Myeloid, Acute/complications/*diagnosis/genetics ; Multiplex Polymerase Chain Reaction ; Myelodysplastic Syndromes/complications/*diagnosis/genetics ; Oncogene Proteins, Fusion/*genetics ; Sequence Analysis, DNA ; *Translocation, Genetic

The aim of this study was to investigate the clinical, pathological and biological features of biphenotypic acute leukemia. The morphology of tumor cells was observed by bone marrow examination; the immunophenotype was assayed by flow cytometry and immunohistochemistry; the chromosomal aberrations were detected by conventional chromosomal analysis and RT-multiplex nested PCR. The results showed that extramedullary skin lesions and myelodysplasia occurred before the onset of overt disease. At the time of diagnosis, this case had more than 30% blasts in bone marrow with meningeal involvement. Large-sized tumor cells predominated morphologically over other cells. Flow cytometry revealed the co-expression of myeloid antigens (cMPO, CD33 and CD117) and T-lymphoid antigens (cCD3, CD5, CD7, dual expression of CD4 and CD8). Immunohistochemical staining showed that CD43 and CD99 were strong positive which define the earliest hematopoietic progenitors. Partial tandem duplication of the MLL gene could be detected with normal cytogenetic method. All above-mentioned results led to the diagnosis of biphenotypic acute leukemia. It is concluded that the biphenotypic acute leukemia is an uncommon type of leukemia which may be preceded by myelodysplastic syndrome and has aggressive clinical and biological behavior. Immunophenotype, cytogenetics and molecular analysis can contribute to early diagnosis of BAL and evaluation of prognosis.
12E7 Antigen ; Acute Disease ; Antigens, CD ; metabolism ; Cell Adhesion Molecules ; metabolism ; Child, Preschool ; Diagnosis, Differential ; Histone-Lysine N-Methyltransferase ; Humans ; Immunophenotyping ; Leukemia ; diagnosis ; genetics ; Leukosialin ; metabolism ; Male ; Myelodysplastic Syndromes ; complications ; Myeloid-Lymphoid Leukemia Protein ; genetics ; Skin Diseases ; complications ; Tandem Repeat Sequences