Laminin expression in advanced laryngeal squamous cell carcinoma does not correlate to neck metastases

Laminins are a family of glycoproteins that consist of one heavy alpha chain and two light beta and gamma chains. The laminin molecule is a major component of the basement membrane and plays an important roles in cell differentiation, adhesion, and migration. It has been reported that laminin is strongly expressed at the invasive front of the tumor and plays an important role in forming the metastases. The aim of the study was to assess the importance of laminin expression in a group of patients with laryngeal carcinoma and neck metastases. The study was carried out on 70 patients with squamous cell carcinoma of the larynx treated at the ENT Department University of Medical Sciences in Poznań. The clinical data consisted of sex, age, stage of the tumor, and histological and immunohistochemical studies. The average time of the follow-up was 3 years. The immunohistochemical study was performed using formalin-fixed and paraffin-embedded tissue sections. Monoclonal mouse anti-human laminin (DAKO, code no. MO638) antibodies were used for immunohistochemistry. To evaluate the laminin staining, a four-point grading system were used: score 0, continuous; score 1, loss of staining <10%; score 2, loss of staining <50%; score 3, loss of staining >50%. The correlation between staining intensity of the laminin and the presence of neck metastases (classified as N-positive "N+" and N-negative "N-"neck) was calculated. All parameters underwent statistical analysis. The patients with advanced clinical disease dominated in our material. Most of the tumors were classified as T3 and T4. A total of 36 patients had metastases to the regional lymph nodes. Positive laminin staining was observed in 62 cases. There was no correlation between laminin staining and occurrence of neck metastases in our studied group (30 N+ and 32 N-). The gravity level in Wilcoxon test was at P < 0.000001 and in Spearman rank order correlation was statistically not significant (P > 0.09).