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 BAL is so difficult that sometimes is misdiagnosed with AML or ALL because the morphology thus the therapy would not have a good effect. Treatment BAL is difficult to treat, most patients receive treatment based on the morphology of blasts and get AML or ALL induction chemotherapy. The induction drug for AML such as cytarabine and anthracycline, drug for ALL such as prednisolone, dexamethasone, vincristine, asparaginase or daunorubicin is common for BAL remission induction therapy. Recently, researches showed that using both myeloid and lymphoid induction therapy may be better for prognosis. Chemotherapy has strong side effects such as typhlitis, gastrointestinal distress, anemia, fatigue, hair loss, nausea and vomiting, etc. Thus, the different dose and times of chemotherapy for different individuals is important. If the patients enter fully remission, the consolidation with stem cell transplantation is highly recommended. Prognosis The prognosis for BAL patients is not good which is worse than ALL and AML. Medical Blood Institute reported cases of CR rate was 31.6%, with a median remission are less than 6 months The median survival time is only 7.5 months. The life quality is also low because the immune function of patient is damaged seriously. They have to stay in hospital and need 24h care. In another study, the results showed that young age, normal karyotype and ALL induction therapy will have a better prognosis than Ph+, adult patients. The study shows median survival of children is 139 months versus 11 months of adults, 139 months for normal karyotype patients versus 8 months for ph+ patients. Recent research Research on the mechanisms of BAL does not show a great progress in terms of the causes, molecular processes and therapy. Some new translocate case of BAL has been reported, such as t(15,17) and t(12,13). For t(15;17), the blasts with morphology of acute lymphoblastic leukemia co-expressed in B-lymphoid and myeloid lineages, and the cytogenetic study showed that the 4q21 abnormalities and t(15;17). However, promyelocytic-retinoid acid receptor rearrangement was not found by fluorescence in situ hybridization on interphase nuclei. Researchers