Myelodysplastic Syndrome/Myeloproliferative Neoplasm with Ring Sideroblasts and Thrombocytosis with Cooccurrent SF3B1 and MPL Gene Mutations: A Case Report and Brief Review of the Literature.

BACKGROUND: Myelodysplastic syndrome/myeloproliferative neoplasm with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T) is a new disease entity in the current WHO classification. Genetically, 60%-90% of cases have mutations in SF3B1, strongly associated with RS, and more than half of them cooccur with JAK2 V617F. This report describes the rare case of MDS/MPN-RS-T with SF3B1 mutation cooccurring with an MPL mutation.

METHODS: We report a 79-year-old man who was referred because of generalized edema. Peripheral blood testing showed macrocytic anemia and thrombocytosis, and bone marrow analysis demonstrated dyserythropoiesis with RS and increased megakaryocytes. A molecular study was performed to detect SF3B1 mutations and recurrent mutations in MPN disease (JAK2 V617F/exon 12, CALR gene exon 9, and MPL gene exon 10 mutations).

RESULTS: The molecular study revealed SF3B1 K666T and MPL W515R mutations, while BCR-ABL1 or JAK2 V617F/exon 12 and CALR mutations were all negative.

CONCLUSION: This is a rare case of concomitant SF3B1 and MPL mutations in MDS/MPN-RS-T.