Coexistence of JAK2 and BCR-ABL mutation in patient with myeloproliferative neoplasm.

The World Health Organisation (WHO) classifies myeloproliferative neoplasm (MPN) into BCR-ABL positive chronic myeloid leukaemia (CML Ph(+)) and Ph(-) MPN. The JAK2 V617F mutation is specific for Ph(-) MPN and occurs in approximately 50% of primary myelofibrosis. Earlier reports suggest that the occurrence of JAK2 and BCR-ABL mutations are mutually exclusive. However, recent reports have documented the coexistence of BCR-ABL and JAK2 mutation in the same patient mostly following treatment with tyrosine kinase inhibitors (TKIs). We thus report a 60-year-old male with atypical clinical and laboratory features of MPN and the presence of both BCR-ABL and JAK2 Mutations.