[Apudomas: nosographic and physiopathological aspects]

The authors intend to contribute to the knowledge of this complex and in part not fully defined subject of apudomas, in particular with regard to classification criteria and physiopathological aspects. After having examined the characteristics of these neoplasias (probably common embryonal origin, similar radioimmunological, immunohistochemical and ultrastructural characteristics, the capacity to convert amine precursors into amines), the authors focus on the most significant aspect of these carcinoids which, in the light of current knowledge, possess varying but undisputed degrees of biological aggressiveness. They also highlight the importance of the gastroenteric tract as an organ with an endocrine function and lastly affirm the value of the classification which, using the pancreas as the reference organ, distinguishes endocrine neoplasias in this tract into entopic and ectotopic examples.