MEN1 and MEN2 are rare inherited cancer syndromes which express a variety of 
endocrine and nonendocrine tumors. The improved knowledge of molecular and 
clinical physiopathology of MEN syndromes, together with the availability of 
genetic testing, have led to earlier detection and intervention, with consequent 
reduction of mortality and morbidity for MEN-associated tumors. Genetic testing 
has gained a key role in the detection of asymptomatic patients harbouring 
mutations responsible for these syndrome, and allows institution of early and 
tailored intervention with a positive impact on the course of disease.