Philadelphia chromosome- positive myelodysplastic syndrome with single lineage dysplasia

Abstract

Myelodysplastic syndrome (MDS) is a group of acquired clonal disorders characterized by dysplastic and ineffective hematopoiesis in the bone marrow. Various specific karyotypic and molecular abnormalities associated with MDS further guide the prognosis. Although translocation t(9;22)(q34;q11) (Philadelphia positive [Ph+]) and corresponding BCR-ABL fusion transcript are classically defined to differentiate CML from non-CML myeloproliferative disorders, it is also associated with adult acute lymphoblastic leukemia (Ph+ ALL), acute myeloid Leukemia (Ph+ AML), myelodysplastic syndrome (Ph+ MDS). The occurrence of Ph+ MDS is very uncommon, and a review of literature has shown by far 40 cases so far in which the majority are seen on progression to Leukemia. Few had de novo presence of such chromosomal abnormality. Due to its rarity, this entity has not yet found its space in the current WHO classification. Also, the role of tyrosine kinase inhibitors in such a scenario is still debatable. We found two such cases of de novo Ph+ MDS diagnosed at institute of medical sciences, Banaras Hindu university and a brief literature review.

Keywords: BCR ABL; Leukemia; MDS; Myelodysplastic syndrome; Philadelphia chromosome.