Multiple endocrine neoplasia--introduction.

Each multiple endocrine neoplasia (MEN) syndrome expresses striking features of hormone oversecretion from its own characteristic group of tissues. Additional expressions include non-hormonal tumours in each MEN syndrome and selected cancers in some syndromes. The complexity of its stereotyped features results in difficult management issues that often justify cooperation across multiple specialties. MEN syndromes, though rare, have long received intense study as models for more common diseases. The syndromal nature often with a large pedigree has promoted recent discovery of the main gene that differs for each of the six MEN syndromes. Each mutant gene has been introduced into clinical decision-making and into further clarification of tumorigenesis. This mini-symposium is related to the 9th International Workshop on Multiple Endocrine Neoplasia in June 2004; it consists of six manuscripts. They report new developments in clinical practices and in basic understandings about this rapidly advancing field.