To assess the value of preoperative ultrasonography (US) - guided skin marking for the investigation of cervical lymph node (LNs) metastasis in papillary cancer patients who had not undergone evaluation of cervical LNs at the initial diagnosis.

We evaluated cervical lymph nodes in 40 patients with papillary thyroid cancer. Ultrasonography wasperformed just prior to surgery. The shape, echogenicity, size, and location of lymph nodes were noted and the location of lymph nodes was marked on the skin surface with a pen under ultrasound guidance. The retrieved lymph nodes underwent intraoperative frozen section analysis to plan the extent of surgery.

One hundred thirty two LNs were detected on preoperative US, 1087 LNs were surgically removed. Of 40 patients, 28 patients had lymph node metastasis. The cystic appearance, the presence of calcifications, hyperechogenicity and the absence of an echogenic hilum were significantly greater in malignant LNs than in benign LNs (P< 0.001). Among these, the cystic appearance and the presence of calcifications showed a very high specificity and seemed to be the most reliable in indicating malignant LNs.

In papillary thyroid cancer patients, preoperatively ultrasound-guided localization of cervical LNs with skin marking shows good potential to determine surgical extent. Ultrasound features of LNs help in the selection of the node to remove with intraoperative frozen section analysis.