This second edition updates the "WHO Classification of Endocrine
Tumours" proposed in 1980 and incorporates many new tumour entities and
pertinent concepts that have developed since that time. It is the result
of a collaborative effort between 9 pathologists from different
countries, in addition to informal contributions and discussions by many
other colleagues. In particular, efforts have been made to integrate
into the fundamental backbone of the histologic classification a number
of prognostic and functional parameters now essential for appropriate
diagnosis and clinicopathologic evaluation of endocrine tumours.