Phaeochromocytoma in multiple endocrine neoplasia type 2: RET codon-specific penetrance and changes in management during the last four decades.

Phaeochromocytoma penetrance and age of diagnosis are highly correlated with MTC aggressiveness based on RET mutation status, with higher penetrance and younger age of diagnosis associated with more aggressive MTC. Penetrance steadily increases with age. At-risk patients require lifelong follow-up.