Mutations in the plasma cell clone identify mechanism of polyneuropathy in a case of POEMS syndrome associated with Castleman disease and multiple myeloma.

Here we present the case of a patient with simultaneous CD, solitary plasmacytoma with minimal bone marrow involvement, and POEMS syndrome followed by progression into multiple myeloma (MM). In CD without clonal plasma cell disorder, the Castleman disease variant of POEMS syndrome may occur and usually presents as a less severe and sensory polyneuropathy [[4]]. The diagnosis of POEMS syndrome requires the two mandatory criteria polyneuropathy and monoclonal plasma cell proliferation as well as one of the three other major criteria (Castleman disease [CD], sclerotic bone lesion, and elevated vascular endothelial growth factor [VEGF]) and one of the six minor criteria [[1]]. [Extracted from the article]