Role of Preoperative Staging Ultrasound for Papillary Thyroid Microcarcinoma

Abstract

Purpose: Papillary thyroid microcarcinoma (PTMC) has an excellent prognosis and can be managed with active surveillance or surgery, dependingon its location and numbers. The authors investigated the role of preoperative staging ultrasound for PTMC with statistical parameters. Methods : : This study included 159 patients with PTMC who underwent thyroidectomy at Kyungpook National University Chilgok Hospital. The tumor size of PTMC, location, bilaterality and multifocality, anterior or posterior aspect of ETE, and metastasis of central/lateral neck lymph nodes were assessed by preoperative thyroid ultrasound and compared with the pathology results. The statistical parameters were calculated and compared. Results : : The incidence of bilaterality of PTMC was similar in the ultrasound and pathology findings, and multifocalitywas identified in 27 cases (17.0%) and 35 cases (22.0%) in ultrasound and pathologic results, respectively. On the other hand, anterior and posterior ETE was identified only in 19 cases (11.9%) in the pathology findings,which was only approximately 50% of that in the preoperative ultrasound (36 cases, 22.6%). In the statistical parameters, most of the parameters were highest when evaluating metastatic lateral neck lymph node and lowest when evaluating metastatic central neck lymph nodes. Conclusion : : Preoperative ultrasound for PTMC was useful to assess the size of PTMC, multifocality, anterior or posterior ETE, and metastatic lateral neck lymph nodes. On the other hand, as it is difficult to predict a central neck lymph node metastasis, it would be better for the operator to consider additional surgery based on the intraoperative findings.

Keywords

• thyroid
• papillary microcarcinoma
• ultrasound