POEMS syndrome is an acronym defined by Bardwick (Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal component and Skin changes). Other various clinical and biological features are reported: edema, cachexia, microangiopathic glomerulopathy, most rarely pulmonary hypertension, cutaneous necrosis. Thrombocytosis or polycythemia may be a prominent feature. POEMS syndrome is sometimes associated with lymphoproliferative disorder. Castelman-like disease is frequently observed as pathologic findings on lymph nodes. Distinction between POEMS syndrome and osteosclerotic myeloma is delicate. The rate of the monoclonal protein is modest-always less than 30 g/L-and is almost of the lambda light chain class. In contrast to multiple myeloma this syndrome is rarely associated with hypercalcemia, skeletal fracture, renal involvement and increasing of M component during evolution. Bone marrow plasmocytosis is usually less than 15% and the kinetic phenotype and genetic characteristics of the plasma cell remain those found in monoclonal gammopathy of undetermined significance. The pathophysiology of this syndrome remains largely unknown but overproduction of pro-inflammatory cytokines are reported, especially TNF alpha, IL-6 and IL-1 beta. Some clinical manifestations seem to be cytokine related. Polyneuropathy and cachexia are the main cause of death. A part corticosteroid and cure of solitary bone lesion, treatment is disappointing and survival is 60% at five years.