Ans. is 'd' i.e. Near total thyroidectomy with radioiodine & radiotherapy As already mentioned in previous question, Total or Near total thyroidectomy is t/t of choice in PTC and also FTC (except minimally invasive cancer). Radioactive iodine '3'1is used post-operatively to detect and destroy any metastatic disease. It is also advised by some expes to do a routine 1311scan and therapy for all patients of differentiated thyroid cancer, postoperatively (except those with occult or minimally invasive disease). Screening with RAI is more sensitive than chest x-ray or CT scanning for detecting metastases; however, it is less sensitive than Tg measurements for detecting metastatic disease in most differentiated thyroid cancers except Huhle cell tumors. External beam radiotherapy is used to treat bone metastasis (to prevent fracture or to control pain). It is also occasionally used to control unresectable, locally invasive or recurrent thyroid carcinoma. There is no role for routine chemotherapy in differentiated thyroid cancers. Other Postop management in differentiated thyroid cancers Thyroid Hormone T4 is given as replacement therapy in patients after total or near-total thyroidectomy, and has the additional effect of suppressing TSH and reducing the growth stimulus for any possible residual thyroid cancer cells. TSH suppression reduces tumor recurrence rates. Thyroglobulin measurement Thyroglobulin (Tg) is produced only by thyroid follicular cells. Following total thyroidectomy, it should be undetectable in serum and any detectable level then indicates the persistence or recurrence of neoplastic disease. This is the basis for the use of Tg as a post-operative tumor marker in the follow-up of thyroid cancer patients Tg levels in patients who have undergone total thyroidectomy should be <2 ng/mL when the patient is taking T4 , and <5 ng/mL when the patient is hypothyroid.