Purpose: To assess the clinical significance of a portable ultrasound system for the diagnosis of lymph node metastasis in patients with oral cancer, we investigated the diagnostic accuracy of sonography as compared with histopathological results.
Materials and methods: From January 2007 through July 2008, 26 consecutive patients with oral cancer who underwent neck dissection were studied. A total of 268 sonographically detected lymph nodes were histopathologically evaluated for metastasis, and a side-by-side comparison of lymph nodes between preoperative sonography and histopathology was performed. The portable ultrasound equipment we used was a GE LOGIQ-e with a 5-13 MHz linear transducer. On sonography, a metastatic lymph node was defined as a lymph node with a minimal axial diameter of more than 8 mm that lacked an echogenic hilum, had a heterogeneous internal structure that reflected central necrosis, or both.
Results: Of the 268 nodes, 45 nodes were metastatic, and the remaining 223 were non-metastatic on histopathological examination. When the lymph nodes were compared between preoperative sonography and histopathological specimens on a side-by-side basis, the sensitivity, specificity, and accuracy for the detection of metastasis were 64.4 %, 98.7 %, and 92.9 %, respectively.
Conclusion: Although the sensitivity was slightly low, our results suggested that the portable ultrasound system was useful for the detection of cervical lymph node metastasis in patients with oral cancer, particularly during postoperative follow-up.