A1) a

Most patients with PTC can expect an excellent prognosis, with the 10-year survival rate greater than 95% for the most favorable stages

Age at diagnosis is the most important prognostic factor in DTC. Diagnosis at an age younger than 40 years is associated
with excellent survival.

(AMES or AGES) LOW RISK HIGH RISK

Age <40 years

Sex Female

Sabiston page 904

ans a) Medullary carcinoma thyroid

Hereditary MTC is identified through  germline RET mutation  

 When to do Prophylactic thyroidectomy

Children identified to harbor the ATA highest-risk RET mutations (i.e., Met918Thr) are recommended to undergo total thyroidectomy in the first year of life.

In children with ATA high-risk mutations (i.e., codon Cys634 and Ala883Phe mutations), prophylactic thyroidectomy is typically recommended before 5 years of age, with the exact timing based on annual clinical examination, neck ultrasound, and serum calcitonin levels starting from the age of 3 years

Children with ATA moderate-risk RETmutations, the timing of prophylactic thyroidectomy should be based on the findings of clinical examination, neck ultrasound, and serum calcitonin concentrations commencing at age 5 years. 

Once calcitonin levels are greater than 30 pg/mL, the likelihood of nodal metastases increases, and this will often necessitate central node dissection, which is associated with increased operative morbidity and a reduction in duration of long-term remission.