Philadelphia chromosome-like (Ph-like) acute lymphoblastic leukemia (ALL) is a newly described, high-risk subtype of B-cell ALL, note the authors of a recent review. Ph-like ALL is characterized by a gene expression profile similar to that of Ph-positive ALL; however, the BCR-ABL1 fusion is not present. The World Health Organization classification of myeloid neoplasms and acute leukemia recently was updated to include the Ph-like or BCR-ABL1-like ALL subtype of B-cell ALL as a provisional entity. Unlike Ph-positive ALL, which is characterized by the pathognomonic BCR-ABL1 fusion, Ph-like ALL is characterized by a multitude of different genetic rearrangements and mutations.

The authors also describe evidence for the use of ruxolitinib, a Janus kinase 2 inhibitor, and dasatinib, a tyrosine kinase inhibitor targeting ABL1 in patients with Ph-like ALL.