RET and multiple endocrine neoplasia type 2B: All experts fully agreed with the need to perform RET testing in subjects at risk for autosomal dominant inheritance of MEN 2 (multiple endocrine neoplasia type 2) or FMTC (Familial Medullary Thyroid Cancer) and, in particular, shortly after birth for MEN 2B and before 5 years of age for MEN 2A and FMTC (ATA-R #3).