Role of prophylactic central neck lymph node dissection for papillary thyroid carcinoma in the era of de-escalation

Thyroid cancer is the most common endocrine malignancy.While there has been no appreciable increase in the observed mortality of well-differentiated thyroid cancer,there has been an overall rise in its incidence worldwide over the last few decades.Patients with papillary thyroid carcinoma(PTC)and clinical evidence of central(cN1)and/or lateral lymph node metastases require total thyroidectomy plus central and/or lateral neck dissection as the initial surgical treatment.Nodal status in PTC patients plays a crucial role in the prognostic evaluation of the recurrence risk.The 2015 guidelines of the American Thyroid Association(ATA)have more accurately determined the indications for therapeutic central and lateral lymph node dissection.However,prophylactic central neck lymph node dissection(pCND)in negative lymph node(cN0)PTC patients is controversial,as the 2009 ATA guidelines recommended that CND“should be considered”routinely in patients who underwent total thyroidectomy for PTC.Although the current guidelines show clear indications for therapeutic CND,the role of pCND in cN0 patients with PTC is still debated.In small solitary papillary carcinoma(T1,T2),pCND is not recommended unless there are high-risk prediction factors for recurrence and diffuse nodal spread(extrathyroid extension,mutation in the BRAF gene).pCND can be considered in cN0 disease with advanced primary tumors(T3 or T4)or clinical lateral neck disease(cN1b)or for staging and treatment planning purposes.The role of the preoperative evaluation is fundamental to minimizing the possible detrimental effect of overtreatment of the types of patients who are associated with low disease-related morbidity and mortality.On the other hand,it determines the choice of appropriate treatment and determines if close monitoring of patients at a higher risk is needed.Thus,pCND is currently recommended for T3 and T4 tumors but not for T1 and T2 tumors without high-risk prediction factors of recurrence.

Correlation between Central and Lateral Neck Dissection in Differentiated Thyroid Carcinoma

Objective: To determine the histopathological correlation between central and lateral neck metastasis in differentiated thyroid carcinoma, and its potential therapeutic impact. Although the central neck dissection (CND) is recommended in differentiated thyroid carcinoma, the indication for lateral neck dissection (LND) remains controversial. Design: Retrospective study. Methods and Main Outcome Measures: Pathological analysis of systematic ipsilateral central neck dissection (CND) and LND performed with total thyroidectomy in differentiated thyroid carcinoma was retrospectively reviewed according to “side” and to “patient”. Results: A total of 56 sides (46 patients) were suitable for analysis. Analysis by “side” revealed that CND and LND dissection samples were both negative in 15 cases, both positive in 32, CND was positive and LND was negative for 8 cases and CND was negative and LND was positive in 1 case. The combined presence of positive LND and positive CND was therefore observed in 32/40 “sides” and 26/46 “patients”. Analysis by “side” of the impact of the treatment decision to perform ipsilateral LND only in patients with positive CND and vice versa demonstrated a sensitivity, specificity, and accuracy of 97%, 65%, and 84%, respectively. Conclusions: In most cases, the presence of positive LND was associated with positive ipsilateral CND. The very low prevalence of positive LND in patients with negative CND may justify LND as a second step procedure only in patients with positive CND, except in the case of documented lateral neck metastasis.