Transient pancytopenia preceding acute lymphoblastic leukemia with positive Philadelphia chromosome

Transient pancytopenia preceding acute lymphoblastic leukemia (pre-ALL) is a rare but well-known occurrence usually affecting children and adolescents. Though pre-ALL in a few adults has ever been reported, the association of this preleukemic syndrome with positive Philadelphia chromosome and P190BCR-ABL is extremely rare. To the best of our knowledge, this is the first report of adult B-cell type pre-ALL with positive Philadelphia chromosome and P190BCR-ABL published in the literature. We report the case of a 49-year-old woman who was diagnosed with B-cell type ALL associated positive Philadelphia chromosome and P190BCR-ABL preceded by transient pancytopenia. The clinical, morphologic, immunophenotypic and molecular features of this patient are described and the literature reviewed.