POEMS syndrome: A multisystem clonal disorder.

Polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes (POEMS) syndrome is a rare condition defined by monoclonal plasma cell disorder, peripheral neuropathy, and other systemic symptoms. The pathophysiology of POEMS syndrome is unknown, but the overproduction of vascular endothelial growth factor (VEGF) appears to be an important contributory element. The diagnosis of POEMS syndrome requires the presence of both mandatory criteria (ie, polyneuropathy and a monoclonal plasma cell disorder), at least one major criterion (ie, osteosclerotic bone lesions, Castleman disease, or elevated serum or plasma levels of vascular endothelial growth factor), and at least one of the six minor criteria. POEMS syndrome lacks a standard treatment, but patients with limited sclerotic bone lesions are typically treated with radiation therapy. In contrast, those with widespread lesions receive chemotherapy and hematopoietic stem cell transplantation.