Efficiency of ultrasonography in assessing cervical lymph node metastasis in oral carcinoma

OBJECTIVES: The study was conducted to assess the value of ultrasonography (USG) for lymph node metastasis in patients with carcinoma of oral cavity. MATERIALS AND METHODS: A total of 20 cases were selected with primary tumor of oral cavity. Ninety-two lymph nodes were detected by ultrasound of 5 mm or more in diameter. The patients were examined preoperatively for palpable lymph nodes clinically and ultrasonographic examination of bilateral neck. Ultrasonographic parameters, such as size, shape, boundaries (well-delineated/ poorly delineated) and internal echoes for the lymph nodes were recorded. RESULTS: The histologic positive rate was 25%, 80% and 93% for nodes between 5 and 10 mm, 10 and 15 mm and for nodes 15 mm or more in size, respectively. Ultrasonographic findings showed a high significance as the size of nodes increases. The positive rate of 86% for the round nodes of 9 mm or more in size showed a high significance. The positive rate was 93% for well-delineated nodes and 68% for poorly delineated nodes. The most frequent echo pattern was homogenous followed by hypoechoic with positive rate for metastasis ranging from 83% to 88%. CONCLUSION: The diagnostic validity of USG as compared with histopathology showed sensitivity of 86% and specificity of 73% with overall efficiency of about 82% in detecting lymph node metastasis. USG is useful for preoperative evaluation of the neck, as the most reliable, inexpensive and easily available method. It is essential for diagnosis, staging and therapy choices.