Neuroendocrine tumors

This chapter presents the definition, classification, incidence/prevalence, economic impact, risk factors, and pathology/pathogenesis of neuroendocrine tumors (NETs). NETs are a spectrum of usually slow-growing neoplasms arising mainly from the gastrointestinal tract, pancreas, and the lung. They originate from the diffuse neuroendocrine cell system, not the neural crest, and can produce biologically active amines and peptides that, when occurring in excess, can cause a variety of clinical syndromes. The chapter also includes the potential pitfalls/common errors made regarding diagnosis of disease, diagnostic and treatment algorithms, prevention/management of complications, important scientific studies, evidence-based clinical data, and essential social guidelines for NETs. Diagnosis is often delayed and metastases are frequently present by the time the correct diagnosis is established. Complete surgical excision is the only cure. Significant palliation and possible survival benefit are obtained by treatment with somatostatin analogs, an increasingly wide variety of chemotherapy agents, and internal radiation by injected radioemboli or peptide receptor radiotherapy.