Feasibility of Sentinel Lymph Node Biopsy in Papillary Thyroid Carcinoma

Jo, Seung Man; Lee, Young Don

Abstract

PURPOSE
Sentinel lymph node (SLN) biopsy (SLNB) for patients with melanoma and breast carcinoma has been validated as an accurate method for assessing the status of lymph nodes. Although prophylactic modified radical neck dissection for patients with papillary thyroidcarcinoma is not performed routinely, central neck node dissection is currently considered to be part of the standard initial operation. Therefore, this study was conductedto determine the feasibility of SLNB for the evaluation of central neck lymph node status in patients with papillary thyroid carcinoma.
METHODS
116 patients (108 women, 8 men) preoperatively diagnosed with papillary thyroid carcinoma between 2004 and 2006 were prospectively studied. After 0.1 to 0.3 ml of 1.0% methylene blue dye was injected into the tumor, SLNB was performed, followed by total thyroidectomy and central neck node dissection.
RESULTS
Preoperatively, in cases of papillary thyroid carcinoma without evidence of cervical lymph node metastasis, the identification rate of SLN in level 6 compartments was 93.1%. In addition, the overall accuracy of SLN at predicting the nodal status was 91.7%. Furthermore, the sensitivity, specificity, positive predictive value and negative predictive values were 85.7%, 100%, 100% and 83.3% respectively.
CONCLUSION
The SLNB in the central compartment for papillary thyroid carcinoma is an acceptable and feasible technique for estimating the central neck lymph node status, therefore, it may be helpful in diagnosing metastases and avoiding unnecessary lymph node dissection in cases of papillary thyroid cancer. However further studies are necessary to improve the diagnostic accuracy prior to routine clinical use.