The patient with 5q minus syndrome and JAK2 V617F mutation with the presence of ringed erythroblasts meeting the criteria of RARS-T effectively treated with lenalidomide – A case report

5q minus syndrome is a form of myelodysplastic syndrome characterized by the presence of an isolated deletion of long arm of the chromosome 5. Patients with 5q minus respond well to the treatment with lenalidomide. The presence of the JAK2 V617F mutation is a common feature of refractory anemia with ring sideroblasts and marked thrombocytosis. Much less is known about effectiveness of lenalidomide in these patients. We present the patient with 5q minus syndrome and JAK2 V617F mutation accompanied by the presence of ringed erythroblasts meeting the criteria of RARS-T. We could identify only two such patients reported in the literature; no details were given about effectiveness of lenalidomide in that group. We observed good response to the treatment with lenalidomide with transfusion independence 9 months after starting of the treatment; however, there was no complete eradication of del (5)(q13q31) clone nor the clone with JAK V617F mutation.