To explore risk factors for posttreatment recurrence of lateral cervical lymph node metastasis in papillary thyroid cancer (PTC) .

The clinical data of 617 consecutive PTC patients with initial presentation of lateral neck metastasis (N1b) at the time of surgery from 1996 to 2009 in our department were retrospectively reviewed. All of the cases received surgery and postoperative L-thyroxine therapy,81 patients were administered postoperative radioactive iodine adjuvant therapy. The risk factors for recurrence including local recurrence and distant metastasis were determined using both univariate and multivariate analyses considering several clinicopathologic variables.

The median follow-up period was 93 months, 466 and 134 patients were followed up for more than 5 and 10 years respectively. 148 (24.0%) patients experienced recurrence with 28 (4.5%) death. Multivariate analyses revealed that age (≥55 years) , primary tumor size, the size of metastatic lymph nodes (> 3 cm) were independent risk factors of local recurrence and distant metastasis (P < 0.05) . The numbers of metastatic lymph nodes (>10) was the risk factor of local recurrence in patients with N1bPTC ( P =0.001 ; RR = 2.022) .

Age, primary tumor size, the size of metastatic LN and the numbers of LN metastases were independent risk factors for recurrence.

Thyroid neoplasms; Lymphatic metastasis; Recurrence