Small atypical cervical nodes detected on sonography in patients with squamous cell carcinoma of the head and neck: probability of metastasis.

Objective. The purpose of this study was to assess the probability of metastasis of small atypical cervical lymph nodes detected on sonography in patients with squamous cell carcinoma (SCC) of the head and neck. Methods. We reviewed, retrospectively and blindly, sonographic findings of 148 patients (118 men and 30 women; mean age, 58.2 years) who underwent curative neck dissection. Each lymph node was classified by using a 4-point scale: 1, definitely benign; 2, indeterminate (small [short-axis diameter 3-cm) metastatic. Lymph nodes were considered atypical if they met at least 1 of the following criteria: a long- to short-axis diameter ratio of less than 2.0, absence of a normal echogenic hilum, and heterogeneous echogenicity of the cortex. These results were verified, on a level-by-level basis, with histopathologic findings. Results. Small atypical nodes were found on sonography in 63 cervical levels of 48 patients, of which 18 (28.6%) were proved to have metastatic nodes. The probability of metastasis was significantly higher with than without a large (>3-cm) ipsilateral metastatic node (0.50 versus 0.20; P = .038) and marginally higher with than without an ipsilateral metastatic node (0.41 versus 0.16; P = .061) but not significantly associated with the T stage of the primary tumor (P = .238) or the presence of an ipsilateral tumor (P = .904). Conclusions. Metastasis was encountered in about 30% of small atypical cervical nodes on sonography in patients with SCC of the head and neck. Our results indicate that small atypical nodes must be interpreted with consideration of metastatic nodes in the ipsilateral neck.