Management of Neuroendocrine Tumor Hormonal Syndromes

Tumors originating in the diffuse neuroendocrine system are characterized by a propensity to secrete a variety of peptide hormones, biogenic amines, and other vasoactive substances. These circulating factors can give rise to a remarkable array of clinical signs and symptoms including flushing, diarrhea, diabetes, hypoglycemia, rash, bronchospasm, and valvular heart disease. Neuroendocrine tumors which produce pathologically elevated hormone levels associated with a corresponding clinical syndrome are termed “functioning” whereas tumors lacking any association with a hormonal syndrome are considered “nonfunctioning.”