A rare version of paraproteinemic hemablastosis, with the onset characterized by Peripheral Nerve Disease, is POEMS- syndrome (Polyneuropathy, Organomegaly, Endocrinopathy, M-protein, Skin Changes). In the foreground of the clinical picture of this oncohematological disease is progressive sensorimotor polyneuropathy, which is the reason for the primary reference to a neurologist long before the provision of specialized hematological care. The article provides an overview of recent scientific publications devoted to this disease. Its pathogenetic mechanisms are discussed, as well as the basis of endothelial growth factor. The authors present their own clinical observation of a 62-year-old patient. The onset of the disease was characterized by polyneuropathy accompanied by changes in the M-protein index, organomegaly in the absence of bone-destructive changes, which made the diagnosis difficult. Additional clinical signs included fever, edema (ascites, exudative pleurisy), and hypoproteinemia, changes in peripheral blood (moderate leukocytosis with a decrease in the level of erythrocytes and platelets, which is atypical), kidney and cardiovascular damage. Despite the specific therapy, the patient’s condition was complicated by the development of infectious complications and was fatal. This clinical observation illustrates the need for a careful differential search for a possible cause of non-polyneuropathy of unknown genesis.