Objective: To investigate the patterns of cervical lymph node metastases from the carcinomas of larynx and hypopharynx.
Method: Chlorophyll solution was injected submucosally into some portions of the larynx and hypopharynx preoperately as a stain of lymphatic system to help conduct modified neck dissections in 50 patiants with laryngeal or hypopharyngeal carcinomas. Searial sections were performed.
Result: The cervical lymph nodes were stained into deep green with a color contrast to the ambient structures, which facilitated the operation of neck dissections and the distinction of lymph nodes. Pathologically positive lymph nodes found in 48% of all the cases. The metastases to level I and V were always associated with other levels. By statistical analysis, there was a higher metastaic rate in level II, III, and V (P < 0.01). Overal 1 occult metastases were recorded in 23.5% of No (clinically negative neck)cases. The involvement were located only at level II or III.
Conclusion: For cN+ (clinically positive neck) patiants, upper and middle jugular vein nodes should be dissected necessarilly,and then appropriate selective neck dissections might be considerd according to the intraoperative findings. For the cN(o) cases with supraglottic or hypopharyngeal carcinomas, it is suggested ipsilateral or bilateral upper and middle jugular vein nodes be dissected according to the clinical status. Chlorophyll as a kind of safe and distinctive stain of lymphatic system can be injected preoperatively routinely.