Controversies about the central compartment in thyroid cancer. Editorial regarding the article "Clinical impact of cervical lymph node involvement and central neck dissection in patients with papillary thyroid carcinoma: a retrospective analysis of 368 cases" by Alexandre Bozec et al

Para-tracheal neck dissection - is dissection of the upper part of level Ⅵ necessary?

Papillary thyroid carcinoma (PTC) has a high propensity for regional metastases, however, the impact of such metastases on the outcome of the patients is minimal. The central compartment of the neck is considered the first and the most common echelon of metastases from thyroid carcinoma. Physical examination along with ultrasonography are the gold standard pre-operative evaluation of patients with PTC. Ultrasonography is highly sensitive in evaluating lateral neck nodes, however, its value in evaluating the central compartment is limited, resulting in a relatively high rate of occult metastases in this compartment. The main potential complications of para-tracheal neck dissection (PTND) are recurrent laryngeal nerve paralysis and hypocalcemia and these may be higher in patients undergoing PTND compared to thyroidectomy alone. New histological data is available showing no evidence of lymph nodes in the central compartment above a level parallel to the inferior border of the cricoid cartilage. These findings support withholding dissection of the upper para-tracheal region routinely as a part of PTND in patients with well-differentiated thyroid cancer. By doing that, the complications may be lower and identical to thyroidectomy alone, thus may abolish arguments against more common use of elective PTND in patients with thyroid carcinoma.

The pros and cons of prophylactic central neck dissection in papillary thyroid carcinoma

Prophylactic central neck dissection (pCND) for management of papillary thyroid carcinoma (PTC) is controversial. Compared to many malignancies, PTC has a high overall survival but local recurrence due to lymph node metastases continue to present management challenges. Unlike lateral cervical nodal metastasis metastasis, central neck nodal metastasis are unable to be reliably detected clinically or radiologically at pre-operative assessment. Residual disease (recurrent or persistent) typically requires re-operative surgery in the central compartment, which carries a heightened risk of significant morbidity. These nodal groups can be accessed during the index thyroidectomy for PTC. Thus, pCND offers potential to reduce the rates of recurrence and the need for re-operative surgery in the central neck. This benefit needs to be balanced with the potential morbidity risk from pCND itself at the index resection. This review will discuss the advantages and disadvantages of pCND with regard to long-term outcomes and potential morbidity. The rationale of pCND will be discussed, along with the indications for ipsilateral and contralateral pCND, the role of re-operative surgery for recurrence and the use of selective versus routine pCND. Strategies to select higher risk patients for pCND with the use of molecular markers will be addressed, along with a discussion of quality of life (QoL) research in PTC.

[Surgical therapy for thyroid gland malignancies]

Surgical therapy for thyroid neoplasms is based on tumor histology and comprises stage-adapted procedures with a high degree of inter-individual variability. This can range from waiting and monitoring, to extensive multivisceral surgery. Grouping together histologically different types of malignancies leads to false assumptions when gauging the radicality of surgery necessary in each particular case. Surgical therapy requires not only an understanding of the biological behavior of the tumor and the risk that it or the therapy poses to the patient, but also knowledge of a wide surgical spectrum of limited and complex resection procedures in the neck and thorax region. The following recommendations are based primarily on the guidelines of the Surgical Working Group for Endocrinology of the German Society for General and Visceral Surgery as well as on the authors' own experience and, where indicated, the guidelines of other working groups.

Well differentiated thyroid carcinoma: current treatment

OPINION STATEMENT

Well differentiated thyroid carcinoma (WDTC) is a relatively common malignancy accounting for an estimated 37,000 thousand cases in the United States in 2009 [1]. WDTC also has a generally high 5 year survival rate that correlates with age. Papillary thyroid carcinoma (PTC) greater than 1 cm is best managed by total thyroidectomy. Thyroid lobectomy and isthmusectomy may be adequate for unifocal PTC less than 1 cm in patients without negative prognostic factors. Central compartment and possible lateral neck dissections should be performed when nodal metastases are present in the respective nodal basins. Post-operatively, radioactive iodine ablation with (131)I followed by thyroid stimulating hormone (TSH) suppression is indicated in certain patients to improve locoregional control and reduce recurrence.