Differentiated thyroid cancer: role of the lymph node dissection.

Thyroid cancer is the most common endocrine malignancy with the highest mortality, so it has generated considerable debate and voluminous literature by endocrinologists, surgeons, and nuclear physicians. If total thyroidectomy is the primary treatment for patients with differentiated thyroid cancers (DTC) and it has proven to be effective and safe, the extent of lymph nodes dissection remains controversial among experts in the field. This controversy persists largely due to the lack of a prospective randomized controlled trial to define whether the addition of central lymph node dissection (CLND) to total thyroidectomy for papillary thyroid cancer (PTC) confers an increased risk of permanent hypoparathyroidism and permanent nerve injury. According to the Consensus Conference of the UEC's Club therapeutic modified radical neck dissection (MRND) should be performed only in the patients with evidence of neoplastic multiple lymph node involvement. Although central lymph node dissection may increase the risk of hypoparathyroidism and nerve injury when compared with total thyroidectomy without CLND, it may decrease recurrence of PTC and likely improves disease specific survival and offers a sufficient alternative to routine prophylactic modified radical neck dissection. Selective central lymph node dissection should be performed, under the care of experienced surgeons, in high risk patients (50 years or older aged, large tumor expansion within the thyroid, or with extrathyroid extension), with the extension to the station II-III-IV in case of single lymph node involvement.