The use of comprehensive preoperative imaging enables complete initial surgical removal of thyroid cancer and associated metastases from cervical lymph nodes, according to the American Thyroid Association’s Statement on Preoperative Imaging for Thyroid Cancer Surgery.
In the recently released statement, Michael W. Yeh, MD, and colleagues from the Surgical Affairs Committee of the American Thyroid Association outlined the importance of preoperative imaging in ensuring complete initial surgery and avoiding the need for reoperation. Preoperative sonographic imaging in patients with known or suspected thyroid cancer is aimed at evaluating the primary tumor and viewing any lymph node abnormalities in the central and lateral neck that warrant surgical removal.
Michael W. Yeh
Ultrasound imaging is currently the gold standard in imaging thyroid cancer, which has high survival rates but also a high risk of recurrence. The primary tumor should be preoperatively assessed for size, location, margin clarity, multifocality and local invasion. Additionally, scans of the central and lateral neck should be evaluated for metastatic involvement of the lymph nodes.
Lymph node abnormalities can be identified based on size, shape, echogenicity, hypervascularity, loss of the hilium and existence of calcifications. If a node is considered suspicious based on these factors, the use of ultrasound-guided fine needle aspiration can serve to validate the need for lymph node dissection in addition to the initial surgery.
Cross-sectional imaging may be indicated in cases of indistinct margins between the primary tumor and the airway, esophagus or major neck vessels. Cross-sectional imaging may also be recommended in patients with severe adenopathy in levels 6 and 4 who have inferiorly located lymph nodes that a difficult to access via ultrasound.
While the use of PET or PET-CT is not recommended prior to initial thyroid cancer surgery, the committee indicated its possible value in viewing recurrent cases in which the tumor markers are positive and anatomic imaging is negative.
According to the committee, effective preoperative imaging of thyroid cancer is essential to ensuring favorable outcomes.
“Thorough preoperative imaging facilitates complete initial surgical clearance of thyroid cancer and associated cervical lymph node metastases,” the researchers wrote. “Ultrasound is the primary imaging modality for thyroid cancer and should ideally be performed by an expert clinician using a standardized methodology that the Committee has described herein.”
Disclosure: The researchers report no relevant financial disclosures.