Long-term follow up of pediatric Philadelphia positive acute lymphoblastic leukemia treated with the EsPhALL2004 study: high white blood cell count at diagnosis is the strongest prognostic factor.

Approximately 3-5% of children with acute lymphoblastic leukemia (ALL) present with Philadelphia chromosome (Ph+). In the pre-tyrosine kinase inhibitors (TKIs) era, Ph+ ALL was associated with a poor prognosis.[1][1]–[10][2] The outcome improved with the use of TKIs.[11][3]–[14][4] Results of