Table 6.

Risk of Aggressive Medullary Thyroid Carcinoma by RET Genotype and Recommended Interventions

Risk of MTCPathogenic Variants 1Recommended Age for Prophylactic Thyroidectomy
HSTp.Met918ThrAs soon as possible in 1st yr of life
Hp.Cys634Arg
p.Cys634Gly
p.Cys634Phe
p.Cys634Ser
p.Cys634Trp
p.Cys634Tyr
p.Ala883Phe		Age <5 yrs
MODAny other RET gain-of-function pathogenic variantMay delay until age >5 yrs if criteria met 2

Adapted from Wells et al [2015]

H = high risk; HST = highest risk; MOD = moderate risk; MTC = medullary thyroid carcinoma

1.

See Molecular Genetics, Table 9 for details of pathogenic variants.

2.

Criteria: normal annual basal and or stimulated serum calcitonin; normal annual neck ultrasound examination; family history of less aggressive MTC

From: Multiple Endocrine Neoplasia Type 2

Cover of GeneReviews®
GeneReviews® [Internet].
Adam MP, Feldman J, Mirzaa GM, et al., editors.
Seattle (WA): University of Washington, Seattle; 1993-2024.
Copyright © 1993-2024, University of Washington, Seattle. GeneReviews is a registered trademark of the University of Washington, Seattle. All rights reserved.

GeneReviews® chapters are owned by the University of Washington. Permission is hereby granted to reproduce, distribute, and translate copies of content materials for noncommercial research purposes only, provided that (i) credit for source (http://www.genereviews.org/) and copyright (© 1993-2024 University of Washington) are included with each copy; (ii) a link to the original material is provided whenever the material is published elsewhere on the Web; and (iii) reproducers, distributors, and/or translators comply with the GeneReviews® Copyright Notice and Usage Disclaimer. No further modifications are allowed. For clarity, excerpts of GeneReviews chapters for use in lab reports and clinic notes are a permitted use.

For more information, see the GeneReviews® Copyright Notice and Usage Disclaimer.

For questions regarding permissions or whether a specified use is allowed, contact: ude.wu@tssamda.

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.