Predictive Factors Related to Lymph Node Metastases in Patients with Papillary Thyroid Microcarcinomas Less than 5 mm in Size / 대한내분비외과학회지

ABSTRACT

PURPOSE: Papillary thyroid cancer is the most common histological type of malignancy that originates from the thyroid. The disease has an excellent prognosis, despite characteristically being associated with lymph node metastases. According to the World Health Organization, a papillary thyroid microcarcinoma (PTMC) is defined as papillary carcinoma measuring ≤1 cm in the greatest dimension. We present the clinico-pathological features and investigate predictive factors related with lymph node metastases in patients with papillary thyroid microcarcinomas less than 5 mm in size. METHODS: Between January 2003 and June 2005, 75 patients underwent surgical treatment for thyroid papillary cancer less than 5 mm in size at the Department of Endocrine Surgery at our hospital. We analyzed the age of patients, gender, presence of symptoms, multifocality, combined thyroid disease, tumor size, capsular invasion, presence of a lymph node metastasis, tumor location, operative method and postoperative complications by use of Pearson's chi-squared test. RESULTS: Lymph node metastases most frequently occurred in patients with a lateral neck mass at presentation (p=0.004). Patients with capsular invasion of the thyroid showed a high rate of lymph node metastases (p=0.027). In patients with combined thyroid disease such as thyroiditis, more lymph node metastases were observed (p=0.018). CONCLUSION: Preoperative symptoms at presentation (especially a lateral neck mass) and tumors with capsular invasion had a high potential to cause lymph node metastases. Factors such as a lateral neck mass, capsular invasion, and combined thyroiditis may be predictive of a lymph node metastasis and are helpful in the determination of proper treatment.