Papillary and follicular carcinomas of the thyroid are differentiated carcinomas developed from the follicular epithelium, that keep some of its morphological and functional characteristics. Their increased incidence is related to an improved screening. Thyroid carcinoma usually presents as a thyroid nodule. Only 5% of nodules are malignant and fine needle biopsy is the most accurate tool for their diagnosis. Initial treatment is standardized and includes a total thyroidectomy with central lymph node dissection in case of papillary carcinoma, that is followed by the administration of a large activity of radioiodine in case of incomplete surgery, distant metastases or high risk factors. Papillary carcinomas of less than 1 cm in diameter, when unifocal and intra-thyroid are treated with surgery only, and radioiodine is not indicated. Thyroxine treatment is given to all patients. The majority of patients are cured, as demonstrated by the work-up performed at 1 year (undetectable serum thyroglobulin following stimulation with recombinant human TSH and normal neck ultrasonography). Subsequent follow-up is yearly with serum Tg and TSH determinations that is maintained within the normal range. In the other patients, other tests may be indicated, starting with the administration of a large activity of radioiodine. In these patients, serum TSH should be decreased to a low level.