A 35-year-old woman with MTC (medullary thyroid carcinoma) has a RET proto-oncogene mutation at codon 634. Her 6-year-old daughter is tested and found to carry the same mutation but is currently asymptomatic. According to ATA risk stratification (MEN2A codon 634 = ATA High Risk), at what age should prophylactic thyroidectomy be offered?

• A After 18 years (at patient's discretion)
• B When calcitonin becomes abnormal
• C At age 12 years — puberty onset
• D Before age 5 years ✓

Explanation

RET codon 634 mutation is classified as ATA High Risk for MTC development; prophylactic thyroidectomy is recommended before age 5 years (some experts recommend age 3–5). ATA Highest Risk mutations (codon 918 — MEN2B) require thyroidectomy within the first 6 months of life. Waiting until calcitonin elevation risks missing a window for curative surgery.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.