MDS with 5q deletion and rare cKIT positive mastocytosis: a diagnostic and therapeutic challenge

A patient with a diagnosis of myelodysplastic syndrome (MDS) with isolated 5q deletion underwent repeat bone marrow biopsy bone marrow biopsy: A medical procedure to remove a small piece of solid bone marrow using a needle that goes into the marrow of the hip bone. The solid bone marrow is examined for cell abnormalities, the number of different cells and checked for scarring of the bone marrow. to assess haematological response after 6 months of initial lenalidomide lenalidomide: Lenalidomide is a capsule that is taken by mouth. It is approved for treating low-risk, transfusion-dependent myelodysplastic syndrome (MDS) patients with an abnormality of chromosome 5q. It is currently in clinical trials to test its efficacy with a broader range of MDS patients. For some MDS… therapy. Subsequent bone marrow bone marrow: The soft, spongy tissue inside most bones. Blood cells are formed in the bone marrow. biopsies revealed persistent MDS with del(5q) in addition to a small atypical mast cell population with >25% of mast cells with spindle-shaped morphology morphology: The study of the structure and form of an organism or one of its parts. and immunohistochemistry characteristics consistent with mastocytosis. Molecular testing on the bone marrow was positive for cKIT D816V and the patient was diagnosed with systemic mastocytosis (SM) with an associated haematological neoplasm. MDS with SM is well known to be associated; however, to the best of our knowledge, only one prior case report identifies MDS with del(5q) and associated cKIT D816V positive mastocytosis. While the exact clonal origin of both chromosomal aberrations is unclear, this case illustrates the therapeutic efficacy of lenalidomide in a patient with MDS with del(5q) and rarely associated cKIT positive SM.