Biphenotypic Acute Leukemia

Biphenotypic acute leukemia (BAL) is a rare disorder comprising 5% of acute leukemias, most likely arising from a multipotent progenitor cell. Knowledge of this disease is limited. There is no single chromosomal abnormality uniquely associated with BAL; however, the most common chromosomal abnormalities are t(9;22)(q34;q11) and structural abnormalities involving 11q23. Whether patients with BAL should be treated with regimens designed for acute myeloid leukemia (AML), acute lymphocytic leukemia (ALL), or combination of treatment for AML and ALL remain unclear. Because of its poor prognosis, it is likely that it might require more intensive treatment approaches, including allogeneic progenitor cell transplantation to achieve long-term complete remissions. In this review, we discuss insights into the molecular biology, diagnosis, classification, prognosis, and treatment strategy of this disease.