Role of preoperative ultrasonography in the surgical management of patients with thyroid cancer

BACKGROUND: Cervical recurrence occurs in up to 30% of patients with differentiated thyroid carcinoma. We retrospectively compared preoperative transcutaneous ultrasonography and physical examination (PE) results in the detection of local-regional metastases (lymph node and soft tissue) in patients with thyroid cancer. METHODS: Data were collected retrospectively from the medical records of patients with thyroid carcinoma who underwent preoperative ultrasonography. Patients were divided into 3 groups: group 1, those undergoing primary thyroid/neck surgery; group 2, those undergoing reoperation for persistent disease; and group 3, those undergoing reoperation for recurrent thyroid carcinoma. For each group, we recorded the frequencies with which ultrasonography detected disease in a neck compartment (central or lateral) that was normal on PE. RESULTS: Two hundred twelve patients underwent operation for primary, persistent, or recurrent papillary (n=130), medullary (n=61), or follicular/Hürthle cell (n=21) carcinoma. Ultrasonography detected additional sites of metastatic disease not appreciated on PE in 21 (20%) of 107 group 1 patients, 9 (32%) of 28 group 2 patients, and 52 (68%) of 77 group 3 patients. The surgical procedure performed was altered by the information obtained from preoperative ultrasonography in 82 (39%) of the 212 patients. Of the 107 group 1 patients, cervical recurrence has been detected in only 6 (6%) at a median follow-up of 36 months, in spite of 67 (63%) having tumors larger than 2 cm or lymph node metastases. CONCLUSIONS: Preoperative high-quality ultrasonography detected lymph node or soft-tissue metastases in neck compartments believed to be uninvolved by PE in 39% of patients. Ultrasound findings altered the operative procedure in these patients, facilitating complete resection of disease and potentially minimizing local-regional recurrence.