Role of prophylactic central neck dissection in cN0 papillary thyroid cancer.

Prophylactic central neck dissection in papillary thyroid cancer is controversial. In this retrospective cohort study, the aim was to assess possible advantages of prophylactic central neck dissection with total thyroidectomy in cN0 papillary thyroid cancer. A total of 244 consecutive patients with papillary thyroid cancer, without clinical and ultrasound nodal metastases (cN0), were evaluated out of 1373 patients operated for a thyroid disease at the Istituto Europeo di Oncologia, Milan, Italy from 1994 to 2006. Of these 244 patients, 126 (Group A) underwent thyroidectomy with central neck dissection, while 118 (Group B) underwent thyroidectomy alone. Demographic, clinical and pathological features were analysed. Overall recurrence rate was 6.3% (8/126) in Group A and 7.7% (9/118) in Group B, with a mean follow-up of 47 (Group A) and 64 (Group B) months. In Group A patients, 47% were pN1a and all patients with recurrence had nodal involvement (p = 0.002). Survival rate did not differ in the two groups. Nine patients were lost to follow-up. Group A patients were older and their tumours were larger in size; according to the pT distribution, a higher extra-capsular invasion rate was observed. The two groups were equivalent as far as concerns histological high risk variants and multifocality. Nodal metastases correlated with stage: pT1-2 vs. pT3-T4a, p = 0.0036. A lower risk of nodal metastases was related to thyroiditis (p = 0.0034). In conclusion, central neck metastases were predictive of recurrence without influencing prognosis. From data obtained, possible greatest efficacy of central neck dissection in pT3-4 papillary thyroid cancer without thyroiditis is suggested.