Immunohistochemical detection of E-cadherin in certain types of salivary gland tumours.
OBJECTIVE
To investigate the topography of E-cadherin and its possible correlation with the histological phenotype of salivary gland tumours.


METHODS
Archival formalin-fixed, paraffin-embedded sections of 54 benign and 56 malignant tumours and 24 samples of normal and inflamed salivary gland tissue were studied immunohistochemically using an Envision/horseraddish peroxidase (HRP) technique.


RESULTS
In normal and inflamed salivary gland samples, E-cadherin was expressed at the membrane of acinar, myoepithelial and ductal cells located at cell-cell contact points. Reduction and/or absence of E-cadherin was only observed in pleomorphic adenoma at the peripheral cells of the duct-like or island structures, or in the cells exhibiting plasmacytoid or stromal differentiation. Neoplastic epithelium in Warthin's tumours and in myoepithelial and oncocytic adenomas was strongly positive. Furthermore, a weak to moderate loss of expression which was related to tissue tumour subtype was seen in malignant tumours such as: adenoid cystic carcinomas; polymorphous low-grade adenocarcinomas; acinic cell carcinomas; and mucoepidermoid low-grade, epithelial-myoepithelial, lymphoepithelial and squamous low-grade carcinomas. Moderate to extreme loss or alternative cytoplasmic non-functional expression were observed in cases of salivary ductal carcinoma, carcinosarcoma, myoepithelial carcinoma, oncocytic adenocarcinoma, unspecified adenocarcinoma and squamous high-grade carcinomas.


CONCLUSIONS
This study suggests a direct association of E-cadherin expression with neoplastic histologic phenotype, which is lost in the more undifferentiated and invasive epithelial salivary gland tumours.
Andreadis
D
D
Department of Oral Medicine and Maxillofacial Pathology, Dental School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
Epivatianos
A
A
Mireas
G
G
Nomikos
A
A
Poulopoulos
A
A
Yiotakis
J
J
Barbatis
C
C
D000230:Adenocarcinoma / Q000737:chemistry*; D000235:Adenolymphoma / Q000737:chemistry; D000236:Adenoma / Q000737:chemistry; D008949:Adenoma, Pleomorphic / Q000737:chemistry; D014408:Biomarkers, Tumor / Q000032:analysis*; D015820:Cadherins / Q000032:analysis*; D003528:Carcinoma, Adenoid Cystic / Q000737:chemistry*; D044584:Carcinoma, Ductal / Q000737:chemistry*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D012466:Salivary Gland Diseases / Q000378:metabolism; D012468:Salivary Gland Neoplasms / Q000378:metabolism*; D012469:Salivary Glands / Q000737:chemistry
D014408:Biomarkers, Tumor; D015820:Cadherins