[An illustrative case of the POEMS syndrome].

POEMS syndrome is a rare and invalidating entity characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy and dermatoses. The diagnosis of this condition is often late and challenging due to the heterogeneity of clinical forms. The light chains secreted by the clonal plasmocytes cause overproduction of VEGF (Vascular Endothelial Growth Factor) responsible for the appearance of the clinical manifestations of POEMS. The diagnostic approach is based on different clinical and biological criteria. Patients with a solitary plasmacytoma are candidates for radiotherapy treatment. Patients with diffuse bone involvement or bone marrow infiltration are best treated by systemic drugs. The response to treatment may take several months before clinical and biological improvement. Early diagnosis and dedicated management limit the clinico-functional impact of POEMS.