Neuroendocrine tumours

Gastroenteropancreatic neuroendocrine neoplasms (NEN) are complex tumours arising from many different sites and expressing a broad range of biological behaviours. Their incidence and that of bronchopulmonary NEN are rising. Recent staging and pathological classification systems aim at improving risk stratification and better categorizing NEN with respect to further therapy. Most tumours are well differentiated, but have frequently metastasized at time of diagnosis; despite this, patients often live for a relatively long time. Some tumours secrete biologically active hormones or peptides resulting in specific symptoms (or syndromes) and may require specific therapy for this, e.g., somataotatin analogue therapy. In advanced disease, a large number of treatments have been shown to be effective, including surgery, systemic chemotherapy, biotherapy (using somatostatin analogues or interferon), targeted therapies, liver-directed strategies (liver embolization or radioembolization) and peptide receptor radionuclide therapy. Recent phase III trials have opened newer therapeutic possibilities, but strategic phase III trials testing the correct sequence of therapy are required to improve overall management in this group of patients. The multidisciplinary approach is essential in optimizing management in patients with NEN.