Acute leukemia of ambiguous lineage: Diagnosis, prognosis and treatment

Acute leukemias of ambiguous lineage (ALAL) are an infrequent subtype of acute leukemias without clear evidence of differentiation to a one single cell lineage. Despite their rarity constitute a recognized subgroup in the recent international classifications, such as the WHO (World Health Organization) classification. Their diagnosis require highly specialized flow cytometry technology, and also cytogenetics and molecular techniques. The low frequency of the disease has made it difficult to find the best therapeutic strategy, due both to the lack of prospective studies and randomized trials, and to the heterogeneity of the published retrospective studies on follow-up and treatment. The group of ALAL has bad prognosis, and usually requires intensive strategies that include consolidation with allogeneic stem cell transplant as part of the treatment. The objective of this review was to analyze diagnosis, treatment and prognosis of this rare subtype of leukemias.