Ján Podoba, Mária Podobová, Marianna Grigerová, Eva Weismanová, Katarína Závodná
Summary: Recommendations on the timing of prophylactic thyroidectomy in patients with familial medullary thyroid carcinoma (FMTC) are based on classification of RET mutations into four risk levels according to genotype - phenotype correlations. Carriers of high risk mutations causing aggressive cancer should be operated in early childhood. On the other hand operation in low risk mutation carriers may be delayed beyond age 5-10 years, when thyroidectomy represents lower risk for the child (patient). Normal annual basal and stimulated calcitonin levels and normal neck ultrasound are a prerequisite in these cases. FMTC provides a unique model for early prevention and cure of cancer and for the stratified roles of mutation - based diagnosis of carriers.