Co-occurrence of monoclonal gammopathy and myelodysplasia: a retrospective study of fourteen cases

Benign and malignant hematologic manifestations in patients with VEXAS syndrome due to somatic mutations in UBA1

Somatic mutations in UBA1 involving hematopoietic stem and myeloid cells have been reported in patients with the newly defined VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome. Here, we report clinical hematologic manifestations and unique bone marrow (BM) features in 16 patients with VEXAS. All patients were male and had a history of severe autoinflammatory and rheumatologic manifestations and a somatic UBA1 mutation (p.Met41). Ten patients had hematologic disorders: myelodysplastic syndrome (MDS; 6 of 16), multiple myeloma (2 of 16), monoclonal gammopathy of undetermined significance (2 of 16), and monoclonal B-cell lymphocytosis (2 of 16), and a few of those patients had 2 co-existing clonal processes. Although macrocytic anemia (100%) and lymphopenia (80%) were prevalent in all patients with VEXAS, thrombocytopenia and neutropenia were more common in patients with progression to MDS. All BMs in VEXAS patients had prominent cytoplasmic vacuoles in myeloid and erythroid precursors. In addition, most BMs were hypercellular with myeloid hyperplasia, erythroid hypoplasia, and varying degrees of dysplasia. All patients diagnosed with MDS were lower risk (low blast count, very good to intermediate cytogenetics) according to standard prognostic scoring with no known progression to leukemia. In addition, 10 of 16 patients had thrombotic events, including venous thromboembolism and arterial stroke. Although VEXAS presents symptomatically as a rheumatologic disease, morbidity and mortality are associated with progression to hematologic disease. Given the increased risk of developing MDS and multiple myeloma, surveillance for disease progression is important.

Myelodysplastic syndromes: moving towards personalized management

The myelodysplastic syndromes (MDS) share their origin in the hematopoietic stem cell but have otherwise very heterogeneous biological and genetic characteristics. Clinical features are dominated by cytopenia and a substantial risk for progression to acute myeloid leukemia. According to the World Health Organization, MDS is defined by cytopenia, bone marrow dysplasia and certain karyotypic abnormalities. The understanding of disease pathogenesis has undergone major development with the implementation of next-generation sequencing and a closer integration of morphology, cytogenetics and molecular genetics is currently paving the way for improved classification and prognostication. True precision medicine is still in the future for MDS and the development of novel therapeutic compounds with a propensity to markedly change patients' outcome lags behind that for many other blood cancers. Treatment of higher-risk MDS is dominated by monotherapy with hypomethylating agents but novel combinations are currently being evaluated in clinical trials. Agents that stimulate erythropoiesis continue to be first-line treatment for the anemia of lower-risk MDS but luspatercept has shown promise as second-line therapy for sideroblastic MDS and lenalidomide is an established second-line treatment for del(5q) lower-risk MDS. The only potentially curative option for MDS is hematopoietic stem cell transplantation, until recently associated with a relatively high risk of transplant-related mortality and relapse. However, recent studies show increased cure rates due to better tools to target the malignant clone with less toxicity. This review provides a comprehensive overview of the current status of the clinical evaluation, biology and therapeutic interventions for this spectrum of disorders.

Concomitant MDS with isolated 5q deletion and MGUS: case report and review of molecular aspects

Patients with monoclonal gammopathy of undetermined significance (MGUS) have a higher risk for the development of concomitant primary cancers such as multiple myeloma (MM) and myelodysplastic syndrome (MDS). We report the case of patient initially suffering from MGUS of the IgG lambda subtype for more than 10 yr, which evolved to MM and MDS with deletion (5q) with severe pancytopenia. Due to pancytopenia, he received dose-reduced treatment with lenalidomide and dexamethasone. He achieved an ongoing transfusion independency after about 1 month of treatment. Bone marrow taken 14 months after start of treatment showed a complete cytogenetic response of the del(5q) clone and a plasma cell infiltration below 5%. In contrast to the development of MM in MGUS patients, the subsequent occurrence of MDS after diagnosis of MGUS is infrequent. Moreover, the biological association of MDS with MGUS is not sufficiently understood, but the non-treatment-related occurrence supports the pathogenetic role of pre-existing alterations of stem cells. Here, we summarize data on concomitant MDS and MGUS/MM with particular emphasis on molecular aspects.