Do the recent American Thyroid Association (ATA) Guidelines accurately guide the timing of prophylactic thyroidectomy in MEN2A?

Background: In 2009, the American Thyroid Association (ATA) published consensus guidelines for timing of prophylactic thyroidectomy (PrThy) for treatment of hereditary medullary thyroid cancer (MTC). The aim of this study was to assess whether the clinical guidelines outlined in the ATA recommendations added to the specific mutation risk level could predict the presence of MTC on final pathology. Methods: A retrospective study was performed of patients undergoing PrThy. We evaluated mutation-based risk levels in combination with 2009 ATA guidelines for resection. Results: Overall, 54 patients underwent PrThy between 1972 and 2009. The median age at PrThy was 11.5 years (range, 2-68). Only 4 patients (8%) underwent PrThy prior to age 5 years. Most patients with MTC (16/22, 73%) had a level C mutation, and the youngest age of MTC in a level C mutation carrier was 5 years. The youngest age of MTC in level A or B carriers was 15 years. The single factor that predicted an overall decreased risk of MTC at the time of PrThy was meeting all ATA mutation-based postponement guidelines for surgical intervention (P = .04). Conclusion: ATA guidelines that includes risk assessment of RET mutation are important in predicting the presence of MTC in patients who are candidates for prophylactic thyroidectomy and in determining the timing of operative resection.