Quantitative Immunohistochemical Analyses of the Expression of E-Cadherin, Thrombomodulin, CD44H and CD44v6 in Primary Tumours of pharynx/larynx Squamous Cell Carcinoma and their Lymph Node Metastases

The quantitative expression of E‐cadherin, thrombomodulin, CD44H and CD44v6 in 32 specimens of primary tumours of pharynx/larynx squamous cell carcinoma and their lymph node metastases was studied by immunohistochemistry. With the aim of obtaining comparative and objective data, image acquisition conditions were kept unaltered for all the measurements and the immunostaining intensity was quantified by applying an image processing system. On the one hand, correlations were only observed between CD44H and CD44v6, both in primary tumours and metastases, and between E‐cadherin and TM in metastases. On the other hand, statistical analyses of paired data did not show significant differences in the expression of these markers between the two tumour sites. In agreement with previous reports, E‐cadherin expression was rather low or negative in primary tumours and metastases of the three poorly differentiated specimens we studied, as well as that of TM, but otherwise some of these samples showed intermediate immunostaining levels of CD44H/CD44v6. It may be concluded from the present study that the quantitative expression of these adhesion molecules in well established lymph node metastases of pharynx/larynx squamous cell carcinoma is essentially unaltered in relation to their primary sites.