A 28-year-old male with MEN2A undergoes prophylactic total thyroidectomy for a RET codon 634 mutation. When should prophylactic thyroidectomy ideally have been performed based on ATA risk category for this specific mutation?

• A Before age 5 years ✓
• B Before age 6 months
• C Before age 10 years
• D At diagnosis, regardless of age

Explanation

RET codon 634 mutation (Cys634 mutations in exon 11) is classified as ATA High Risk (category C) for medullary thyroid carcinoma development in MEN2A. ATA guidelines recommend prophylactic thyroidectomy before age 5 years for this risk category. The highest-risk mutations (codon 918, M918T, MEN2B) require surgery before 6 months, while moderate-risk mutations (category A, codons 609/611/618/620) may be observed until age 5–10 years with normal calcitonin.

Reference: Bailey & Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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