The diagnostic value of ultrasonography to detect occult lymph node involvement at different levels in patients with squamous cell carcinoma in the maxillofacial region

The purpose of this study was to evaluate ultrasonography (US) and computed tomography (CT) in detecting lymphnodes of the neck affected with squamous cell carcinoma. From 1987 to 1999 the data from 203 untreated patients with a diagnosis of cancer in the maxillofacial have been investigated. Of these, 115 had a primary squamous-cell carcinoma. US diagnosis was made by an oral- and maxillofacial surgeon experienced in US of the head and neck. CT diagnosis was made by a well-experienced radiologist. The following lymph node levels were assesed: level I (submental and submandibular lymphnodes), level II (lymphnodes distal to level I and confined to the region above the skin crease at or just below the level of the thyroid notch), level III (lymphnodes distal to level II and confined to the anterior cervical triangle including those deep to the sternocleidomastoid muscle), and level IV (lymphnodes distal to level III and confined to the posterior cervical triangle). For all levels US yielded a sensitivity of 71%, and a specificity of 87%, while CT showed a sensitivity of 32% and a specificity of 96%. The sensitivity of US decreased from level I to level IV, whereas the specificity increased from level I to level IV. For lymphnode levels I and II US may be useful for the detection of local metastases while for the other levels the application of advanced techniques Of US may have to be investigated.