Transformation of primary myelofibrosis with 20q− in Philadelphia-positive acute lymphoblastic leukemia: Case report and review of literature

A 56-year-old male with chronic idiopathic myelofibrosis and cytogenetic finding of 20q− after a period of 10 months developed acute Philadelphia-positive lymphoblastic leukemia. Immunophenotyping of peripheral blood by flow cytometry showed HLA-DR, CD34, CD19, CD22, CD10, CD33, and CD11b positivity. Cytogenetic analysis revealed the presence of 20q− and Philadelphia chromosome t(9;22)(q34:q11) at the time of disease transformation to ALL. The JAK2V617F mutation was not found. This is a very rare case of simultaneous presence of two cytogenetics abnormalities and evolution of primary idiopathic myelofibrosis to Philadelphia-positive acute lymphoblastic leukemia.