The immunohistochemical analysis of the proliferative activity and the maturity degree of lymphatic vessels in oral squamous cell carcinomas.

Oral cancers still represent a major health problem; regional lymph node metastases occur in 30-40% of head and neck squamous cell carcinomas and are associated with unfavorable prognosis and decreased survival. The study included 35 cases of oral squamous cell carcinomas (OSCC), which were analyzed by double reactions to determine the proliferative activity (anti-human D2-40/Ki67) and the maturity degree (anti-human D2-40/α-SMA) of lymphatic vessels, both intratumoral (IT) and in the advancing edge (AE), and in relation to clinicopathological prognostic parameters. The mean values of D2-40 lymphatic vessel density (LVD) were higher in AE then in IT level. Poorly differentiated carcinomas, T3/T4, presented the highest LVD values, both IT and in the AE. LVD was higher in advanced stages and metastasizing carcinomas. Ki67 was positive in all cases, Ki67 proliferation index (IP) indicated higher values in poorly differentiated carcinoma, T3/T4, metastasizing ones, both IT and in the AE. LVD and IP Ki67 showed a positive linear correlation. D2-40/Ki67-positive vessels were identified only at the AE or close to it. D2-40/Ki67 LVD had highest values in advanced stages carcinoma, with metastases. D2-40/α-SMA-positive vessels were identified only in the neighborhood of the tumor and LVD highest values were present in early-stage carcinomas and without metastases. A negative linear correlation between proliferation and maturity of the lymphatic vessels was found. The study indicated a strong association between lymphatic proliferative activity and lymph node metastases, suggesting the need for targeted antilymphangiogenic therapies in OSCC.