Following observation of the symptoms, the patients need to get complete blood counts and a bone marrow examination. If the patient has<unk> , the morphology and immunophenotype check is needed to make sure the type of<unk> . The morphology of the blast in<unk>  is not certain. The cells could display both myeloid lineage and lymphoid or undifferentiated morphology. Therefore, the diagnosis cannot based on the morphology result. The immunophenotype check is the most important basis of the diagnosis of<unk> . Before 2008, the diagnosis of<unk>  was based on a score system proposed by the European Group for the Immunological Classification of<unk> s (EGIL) which could differentiate from other kinds of acute<unk> . The table shows this method. If the score of only one lineage is higher than 2, the acute<unk>  could be acute myeloid<unk>  (AML) or acute lymphoblastic<unk>  (ALL). According to the original EGIL scoring system<unk>  is defined when scores are over two points for both myeloid and T- or B- lymphoid lineages. In 2008, WHO established a new and strict criteria standard for diagnosis of<unk> . The presence of specific T-lymphoid antigens, cytoplasmic CD3 (cCD3), MPO and CD 19 became the most important standard for recognizing the lineage. Other B-lineage markers (CD22, CD79a, CD 10) and monocytic markers are also needed. Table 2 shows the method. Compared with the EGIL scoring system, the current 2008 WHO criteria applied less but more specific markers to define the lineage of the blasts, and incorporated the intensity of markers expression into the diagnostic algorithm. The diagnosis of<unk>  is so difficult that sometimes is misdiagnosed with AML or ALL because the morphology thus the therapy would not have a good effect.
Biphenotypic acute leukaemia
Aggressive NK-cell leukemia
Mixed-phenotype acute leukemia
Leukemoid reaction
Atypical chronic myeloid leukemia
Prolymphocytic leukemia
T-cell prolymphocytic leukemia
B-cell prolymphocytic leukemia