抄録
Seventy-three patients treated for cancer of the oral cavity between 1997 and 2004 were retrospectively reviewed, especially diagnosis and management of lymph node metastasis. Standard methods of diagnosing and treating cancer of the oral cavity were used. Metastatic lymph node was defined as shown as minor axis/major axis >0.5, and minor axis >6mm (Levels I, II), 7mm (III-V) on ultrasonic echo.
Fifty-four cases underwent neck dissection. Seven cases of N0 (40 cases) were positive for metastasis histopathologically. Fourteen cases were determined to be positive for metastasis by preoperative Ultrasonography (US) and they all were found to be positive in histopathological examinations after operations.
Thirty-eight cases of T2 were performed neck dissection. Nine cases were determined to be positive for metastasis by preoperative US. Five cases were positive for metastasis on frozen section biopsy (FSB). Three cases showed occult metastasis. There were 17 histologicallly positive nodes in T2 (40.4%).
Many reports suggest that the prognosis of cancer of the oral cavity depends on the number of metastatic lymph nodes. However, since it is often difficult to detect the number of positive lymph nodes by US, there is a high possibility that there will be multiple metastatic lymph nodes when one metastatic lymph node is detected on US. It is necessary for us to establish a diagnostic standard for metastatic nodes and to identify metastatic nodes by prophylactic neck dissection.
