Familial Medullary Thyroid Cancer: Five-year Review of the Most Frequent Mutations in the RET Gene: An Update

Background: Familial Medullary Thyroid Cancer (FMTC) is hereditary in 25% of cases. Patients with an inherited form of FMTC usually have a germline mutation in the RET proto-oncogene (10q11.2); these mutations generally occur in exons 10 (codons 618 and 620) and 11 (codons 630, 631, and 634). Methods: A narrative review of articles focused on the pathology of familial medullary thyroid cancer was carried out using the next databases PubMed, ScienceDirect, BMC, Springer, Frontiers, PMC, Wiley Online Library, Cold Spring Harbor and ELSEVIER. This search was carried out between August and September 2021. Results: 19 studies were selected in which the following mutations were found: five studies (26.31%) reported mutation in exon 10; three studies (15.78%) in exon 11; three studies in exon 13 (one of them associated with a rare mutation in exon 7) (10.52% plus 5.26%); three studies (15.78%) in exon 14; two studies (10.52%) in exon 15; two (10.52%) in exon 16; and one (5.26%) rare FMTC NO RET. The two most frequent mutations were in codons 620 of exon 10 and 804 of exon 14. Conclusion: The findings of this review are consistent with the medical literature, finding the most common RET mutations in exon 10 and codon 620. It is essential that in patients with a presumptive diagnosis, genetic studies (identification of germline mutations in the RET proto-oncogene, located on chromosome 10q11.2) be performed