[Current concepts on diagnosis and treatment of carcinoid].

Carcinoid tumours are relatively rare neuroendocrine neoplasms that often present as diagnostic dilemmas due to obscure or non-specific symptomatology. They can originate from any location in the body and on the basis of their localisation are traditionally described as originating from the foregut, midgut, and hindgut. Carcinoids occur most frequently in the gastrointestinal system, where they are most common in the small intestine, appendix, and rectum, and in the bronchi. Although, the majority are nonfunctional, some carcinoids can cause so called classical or atypical carcinoid syndrome and sometimes also paraneoplastic syndromes. Carcinoid tumours often present with metastatic disease. Recent years have brought new developments in the field of their diagnostic and treatment options. Despite the fact that many advances have been made in both the basic science and clinical areas, the optimal treatment of carcinoid tumours is still a matter of debate. In this article, the pathogenesis, clinical aspects, classification, diagnosis and treatment of carcinoids are reviewed including the latest advances in each area.