ABSTRACT
Gastrointestinal endocrine tumors comprise a diverse group of tumors. They are classified as “functional” or “nonfunctional” depending on whether the clinical syndrome is due to hormone release. Advances in knowledge and technology have improved our understanding of these tumors and enhanced our ability to diagnose and treat the resulting clinical syndromes. This chapter summarizes the clinical syndromes associated with the important functional gastrointestinal endocrine tumors (Table 1).
