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[The distribution of metastatic cervical lymph nodes in laryngeal carcinoma].

OBJECTIVE
To detect regularity of lymph nodes metastasis of laryngeal carcinomas and determine the best kind of neck dissection.


METHOD
The series consist of three parts:the distribution of laryngeal carcinoma with metastasis lymph nodes, the immunohistochemical evaluation of micrometastases after pathologic diagnostic N0, the distribution of recurrence after operation. All 289 cases in these series including 174 cases of supraglottic carcinoma, 113 cases of glottic carcinomas and 2 cases subglottic carcinomas.


RESULT
In the first part, there were 242 necks had been conducted neck dissections and the metastases rates from level I to level VI is 2.8%, 98.3%, 32.6%, 15%, 13%, 21.4% respectively. In the second part, 46 (50 necks) of 71 cases of pathologic N0 necks conducted immunohistochemical study in the lymph nodes. 13 lymph nodes harbor micrometastases, which distributes in 11 cases. All the positive lymph nodes located in level II. In the third part, 45 necks of 37 cases were evaluated the cervical metastasis without neck dissection. The metastases rates from level I to level V is 2.2%, 100%, 48.9%, 26.7%, 13.3% respectively.


CONCLUSION
The metastatic lymph nodes of laryngeal carcinomas distribute mainly in level II and level III, followed by level IV and level VI, but rarely in submandibular and posterior triangles. The neck dissection of laryngeal carcinomas should be conducted in the regions from level II to level IV. The dissection of level I and level V should be spared unless there is evidence of metastasis to these regions so as to shorten the operation time and avoid postoperative complications.