Cervical Lymph Node Metastases After Thyroidectomy for Papillary Thyroid Carcinoma Usually Remain Stable for Years.

BACKGROUND: Lymph node (LN) recurrence detected by ultrasound (US) is a very common problem after initial treatment for papillary thyroid carcinoma (PTC). Most patients with PTC have an excellent disease-specific survival even with LN recurrence. Recently, watchful waiting with serial cervical US evaluations would be considered a reasonable approach to management of LN recurrence in selected patients. On the other hand, some patients with LN recurrence have demonstrated clinically significant disease progression during follow-up. The objective of the present study was to document the changes of cervical LN metastases after initial treatment and identify useful information for deciding how best to manage individual patients with LN recurrence.

METHODS: This retrospective review identified 83 consecutive PTC patients with at least one LN on the postoperative US diagnosed with fine needle aspiration biopsy or the thyroglobulin titer in the wash-out of the needle. The change in LN size was determined using serial US studies over time.

RESULTS: The subjects were 15 men and 68 women, with a median age at initial surgery of 50.6 years (range, 18-80 years). The median LN size at the start of the observation period was 1.3 cm (range, 0.5-2.4 cm) in the largest diameter. After a median follow-up of 7.2 years, the median growth rate of the nodes showing structural progression was 1.4 mm per year (range, 0-12.0 mm/year). Seventeen of 83 patients (20.5%) demonstrated an increase in LN size of at least 3 mm, only 8.4% (7 of 83) had an increase of at least 5 mm, and 39.7% (33 of 83) resolved. Distant metastases were present in 11 of 83 patients. Ten-year and fifteen-year disease-specific survival rates after diagnosis of LN recurrence were 84.7% and 72.6%, respectively. Older age and recurrent LN growth of more than 3 mm/year were recognized as independent predictors for short survival on both univariate and multivariate analyses (p < 0.05).

CONCLUSIONS: Most lymph node recurrences may remain stable for a long time and not be immediately life-threatening. However, recurrent LN growth of more than 3 mm per year could be related to mortality.