Background and objectives: The importance of nodal involvement as a prognostic factor in differentiated carcinoma of the thyroid gland remains controversial. We therefore attempted to confirm the prognostic factors in differentiated thyroid carcinoma, with special reference to nodal status.
Patients and methods: A total of 139 patients with differentiated thyroid cancer followed for 2-27 years, with a median follow-up of 7 years were studied. All patients underwent surgical resection, either subtotal, total, or lobectomy, with modified radical neck dissection. Survival was calculated using the Kaplan-Meier method.
Results: Ten (7%) patients have died from thyroid cancer. Adverse prognostic factors included age >45 years (P=0.0120), the presence of distant metastases (P=0.0006), and TNM stage (P=0.0002). The number of lymph nodes dissected ranged from 6 to 92, with an average of 26. Lymph node metastases were found in 102 (73%) patients. There was no difference in survival according to the level of nodal disease by the TNM classification. Furthermore, the number of cervical lymph nodes involved had no effect on the survival.
Conclusion: Our results suggest that the presence of histologically confirmed lymph node metastases is not an important prognostic factor in patients with differentiated thyroid carcinoma.