It was relatively recently that thyroid surgeons believed reoperation in the central neck was acceptable, given the risks [40]. It is imperative that before any reoperation, the function of the RLNs as well as location of the remaining parathyroid glands be confirmed and documented. Incision for reoperative is usually positioned on the previous thyroidectomy scar in the lower neck. The incision may have to be extended laterally on the side of disease for easier visualization. When re-elevating the subplatysmal flaps and freeing the strap muscles in the midline substantial fibrosis is often revealed, especially if haemostatic agents were previously employed. The RLN and parathyroid pedical identification and preservation are crucial to a central neck reoperative setting. Evidence shows that RLN monitoring may help the surgeon distinguish fibrotic areas close to the nerve from recurrent disease [41]. Some surgeons identify the RLN from a previously undissected region vis-a-vis the lateral or lower neck [36]. The personal preference of the present authors is to define the common carotid artery from the thoracic outlet to the level of the cricoid and then attempt to identify the RLN as low as possible in the paratracheal position in the superior mediastinum. The RLN must be followed from its entry into the operative field towards its cephalic location, staying on the anteromedial border of it. An alternative to continuous nerve monitoring is to use intermittent nerve stimulation to confirm function in the absence of long-acting muscle relaxants. Visualizing the remaining inferior thyroid artery may help to identify the main pedicles to the parathyroid glands. The inferior gland is likely to be sacrificed as a result of scar/tumour involvement. The superior parathyroid is usually above the RLN angle and not at as much risk. Any devascularized (dark brown/black) parathyroid gland is excised and preserved for autotransplantation after histological confirmation. Once the surgeon is confident of the identification and preservation of these structures, resection of all lymph nodes within the borders of the central neck may ensue. Identifying the surfaces of the trachea also helps with identifying existing disease. A comprehensive resection is performed on the ipsilateral side, removing all nodal tissue in the area from the trachea to the carotid and from the cricoid down to the innominate artery. Attention must be paid to ensure that all macroscopic disease in level VII is detected and excised as well. A decision with respect to contralateral dissection is made at this juncture. Some authors recommend bilateral excision at the time of this procedure; others, including the present authors, will only perform bilateral central dissections if documented evidence exists of contralateral disease and the RLN on the first side has been identified and deemed functional. If lateral masses or lymph nodes are palpable, a more extensive operation is considered.

Reoperating in the central neck for recurrent WDTC has varied reported outcomes. Clayman et al. report that 71 % of patients had their Tg reduced to undetectable levels [34]. Shah et al. report normalization (≤2 ng/ml) of Tg in only 56 % of patients [42]. Both studies followed patients for 18 and 28 months, respectively. Other studies looking at both the central neck as well as reoperation in the lateral neck show similar response rates to those mentioned above [43, 44]. Aggressiveness of disease as predicted by time to recurrence, burden and subtype of tumour and level and trajectory of Tg marker determine outcomes for re-recurrence of disease.

CNLND and treatment of recurrence continue to cause much debate among thyroidologists. With improved detection of occult disease and further biochemical analysis of thyroid tumours, the surgeon may better predict response to intervention. Tufano et al. correlated BRAF genetic mutated tumour status with the length of time to central neck recurrence from the initial operation [45]. Those individuals with the mutation had a shorter time to reoperation and a higher number of metastatic central neck lymph nodes [46]. With further knowledge of this disease at a molecular and genetic level, we can begin to stratify patients with worse tumour prognosis to more aggressive surgical management. Disease-free survival is an appropriate marker to use when evaluating the effectiveness of surgical intervention. The obstacle, however, is in following patients long enough to account for the indolent nature of WDTC.