Background and Objectives The aims of this study were to evaluate the rate and risk factors involved in bilateral central lymph node metastasis in patients with papillary thyroid cancer (PTC) located in the isthmus compared to tumors located in other thyroid regions, and to use those findings to establish a surgical strategy for treating these tumors.
Subjects and Method We compared the clinical and pathological data of 48 patients with isthmic PTC and 141 patients with PTC located in other thyroid regions, all of whom underwent total thyroidectomy and bilateral central neck dissection.
Results The rates of bilateral central lymph node metastasis were higher in the isthmus group than the nonisthmus group (29.2% vs 9.9%; p = .001). On multivariate analysis, isthmic location of the tumor was an independent risk factor for bilateral central lymph node metastasis (OR = 3.458; p = .005). But, the positional relationship between the tracheal midline and the nodule was not clear in lymph node metastasis in the isthmus group.
Conclusion Bilateral central neck dissection should be considered for isthmic PTC regardless of the relation between nodule and tracheal midline because of the high rate of bilateral central lymph node metastasis.