Essential thrombocythemia with deleted 5q – a genetic and morphologic hybrid?

Myeloid neoplasm with isolated del(5q) and the MPLW515L mutation fulfills the WHO diagnostic criteria for ET

A 70-year-old male was referred to our hospital for marked thrombocytosis without anemia. The patient simultaneously presented with an MPL W515L mutation, one of the major driver mutations in essential thrombocythemia (ET), and deletion of 5q, a characteristic cytogenetic abnormality in myelodysplastic syndrome (MDS). Bone marrow examination showed a combination of both mature hyperlobulated megakaryocytes, as found in ET, and small hypolobulated megakaryocytes, typically found in MDS with del(5q). The present case is consistent with the recently proposed category of myeloid neoplasms with isolated del(5q) and an MPN driver mutation.

Diagnosis of del(5q) MDS, 14 Years after JAK-2 Positive PV Appearance: Complete Remission of both Diseases with Lenalidomide Monotherapy

This is the report of the clinical case of a patient who presents the association of a JAK-2 positive chronic myeloproliferative neoplasia to a subsequent 5q- myelodysplastic syndrome, developed after about 14 years from the first diagnosis. Patient’s symptoms had rapidly worsened, and she became transfusion-dependent. Therapy with low-dose Lenalidomide quickly reduced the splenomegaly and completely brought white cells counts, haemoglobin, and platelets back to normal. After more than one year from the start, blood cell count is still normal. As far as we know, this is the first case of an effective treatment with Lenalidomide reported in this clinical setting.

Myelodysplastic disorders carrying both isolated del(5q) and JAK2(V617F) mutation: concise review, with focus on lenalidomide therapy

The concomitant presence of del(5q) and JAK2(V617F) mutation is an infrequent event which occurs in rare patients with peculiar cytogenetic, molecular, morphological and clinical features, resembling those of both myelodysplastic syndromes and myeloproliferative neoplasms. Lenalidomide may induce rapid, profound, and long-lasting responses in a subset of these patients. However, the mechanism(s) by which the drug acts in these conditions remain not completely elucidated. A new case report and a review of all cases published so far in this setting are provided. Furthermore, the possibility of categorizing - from a clinical, pathological, and biological point of view - for at least some of these patients as a potential distinct entity is discussed.