Pre-operative ultrasound diagnosis of nodal metastasis in papillary thyroid carcinoma patients according to nodal compartment.

The aim of this study was to assess the accuracy of ultrasound (US) and individual US features in the diagnosis of nodal metastasis in patients with papillary thyroid carcinoma (PTC) with respect to nodal compartment. US diagnoses and individual US features of nodal metastases with respect to nodal compartment were investigated in 184 consecutive PTC patients who underwent pre-operative US. Histopathologic results were used as a reference standard. One hundred thirty-six of 368 (37.0%) central compartments contained one or more metastatic nodes, whereas 44 of 48 (91.7%) lateral compartments had one or more metastatic nodes. The malignancy rates of suspicious US diagnoses in the central and lateral compartments were 66.3% (53/80) and 93.3% (42/45), respectively. The central and lateral compartments differed significantly in nodal composition, echogenicity, calcification, shape, hilar echogenicity and vascularity. The accuracy of US in the diagnosis of nodal metastases from PTC was lower in the central compartment than in the lateral compartment.