喉頭内のリンパ管分布及び喉頭癌におけるラミニン<SUB>γ</SUB>2鎖発現による検討

Abstract

Objectives : The potential spread of laryngeal cancer was investigated by the analysis of lymphatic vessels' distribution in the normal larynx. The study involved immunostaining for the lymphatic endothelial marker, D2-40, and expression patterns of laminin gamma 2 chain (LNγ2) in laryngeal cancer.Results : In the normal larynx we found that many lymphatic vessels existed in the submucosal region except for the vocal cord. In addition, lymphatic vessel density in the pre-epiglottic space and the cricoid area were lower than in the submucosal region, and there were few lymphatic vessels in paraglottic space. In laryngeal cancer specimens, lymphatic vessels existed in 12 out of 23 cancer tissues. Of these twelve patients, five showed cervical lymph node metastases or recurrences. The eleven other patients whose cancer tissues were negative for lymphatic vessels didn't show metastases or recurrences (p< 0.02). We also defined three patterns of LNγ2 expressions in laryngeal cancer ; peripheral expression, diffuse expression and no expression. The disease's specific cumulative survival rates for patients with diffuse expression and the other expressions were 58% and 100%, respectively (p< 0.05).Conclusion : The presence of lymphatic vessels and diffuse expressions of LNγ2 indicate a considerable risk for cancer progression and are closely related to the prognosis. These factors may be prognostic in-dicators for squamous cell carcinomas of the larynx as well.