Parotid carcinoma: expression of kit protein and epidermal growth factor receptor.

OBJECTIVES

Our aim is to investigate the expression of kit protein (KIT) and epidermal growth factor receptor (EGFR) in parotid carcinomas in order to correlate the expression to histology and prognosis. Further we want to perform mutation analysis of KIT-positive adenoid cystic carcinomas.

PATIENTS AND METHODS

Formalin-fixed paraffin-embedded sections from 73 patients with parotid gland carcinomas were used for the study. The sections were stained with both KIT and EGFR polyclonal antibodies. Twelve KIT-positive adenoid cystic carcinomas were examined for c-kit mutation in codon 816.

RESULTS

Of all carcinomas 25% were KIT-positive and 79% were EGFR-positive. Ninety-two percentage of the adenoid cystic carcinomas were KIT-positive. None of the adenoid cystic carcinomas had mutations in codon 816 of the c-kit gene.

CONCLUSION

Neither KIT- nor EGFR-expression seem to harbour significant prognostic information. Adenoid cystic carcinomas express KIT, but no mutations in codon 816 of the c-kit gene were identified.