Case Report: Secondary myelodysplastic syndrome following autologous stem cell transplantation in a patient with POEMS syndrome.

This article reports a rare case of a patient with POEMS syndrome who developed secondary myelodysplastic syndrome (MDS) two years after undergoing autologous stem cell transplantation (ASCT). The patient was initially misdiagnosed with chronic inflammatory demyelinating polyneuropathy (CIDP) due to symptoms of limb numbness and weakness. Two years later, the diagnosis was corrected to POEMS syndrome. After induction therapy with the lenalidomide-dexamethasone (RD) regimen, ASCT is performed and partial remission is achieved. And lenalidomide was used for maintenance therapy. Over a year later, he was infected with SARS-CoV-2 and subsequently developed pancytopenia. Bone marrow routine revealed increased myeloblasts with multilineage dysplasia, and next-generation sequencing (NGS) found a TP53 mutation, leading to the diagnosis of secondary MDS. The pathogenesis of secondary MDS in POEMS syndrome is discussed from three aspects: cytotoxic therapy, genetic predisposition, and SARS-CoV-2 infection. This case underscores the importance of prolonged surveillance for secondary myeloid neoplasms (sMN) in POEMS patients and suggests that early genomic profiling and individualized treatment may improve outcomes.