Incidental positive lymph nodes in patients with papillary thyroid cancer is independently associated with recurrent disease.

ABSTRACT

BACKGROUND AND OBJECTIVES: Pathological examination occasionally reveals incidental central lymph nodes metastasis (iLNM) after thyroidectomy for patients with papillary thyroid cancer (PTC) who did not undergo compartment-orientated lymphadenectomy. We aimed to investigate the risk of recurrence for patients with iLNM. METHODS: We conducted a retrospective review of all patients undergoing total thyroidectomy for PTC (January 2000 to January 2010). Patients with distant metastases, central- or lateral neck dissection and pre-operative suspicious lymph nodes (by ultrasound or clinical examination) were excluded. The association between iLNM and recurrent disease was investigated using Kaplan-Meier survival estimates and Cox proportional hazards analysis. RESULTS: 225/1000 patients had incidental nodes after total thyroidectomy for PTC. 183 were node-negative and 42 had iLNM. Mean age was 46 years and 201 (89%) were women. Mean number of resected nodes was 2.3. Disease recurred in 8/183 (4.4%) of patients with N0 versus 7/42 (17%) with iLNM. After adjusting for other factors, iLNM was independently associated with recurrent disease (hazard ratio = 4.01 [95% CI 1.21-13.3]). CONCLUSIONS: Positive incidental lymph nodes are independently associated with recurrent disease in patients with PTC. These patients should therefore be monitored more carefully.