c-kit and bcl-2 Are Not Useful Markers in Differentiating Adenoid Cystic Carcinoma from Polymorphous Low-Grade Adenocarcinoma

Abstract

Aims. To evaluate the immunohistochemical expression of bcl-2 and c-kit proteins in the salivary gland tumors, adenoid cystic carcinoma, and polymorphous low-grade adenocarcinoma with a view to tumor differentiation. Methods. Immunohistochemical studies were performed on 29 adenoid cystic carcinoma and 23 polymorphous low-grade adenocarcinoma archival cases with bcl-2 and c-kit antibodies using standard procedures, and the data were statistically analyzed. Results. The difference in bcl-2 expression in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma was not statistically significant. Whilst the difference in c-kit expression was statistically significant (), the difference proved small so as to be of no practical or diagnostic importance. Moderate to strong immunostaining was noted in adenoid cystic carcinoma with c-kit, the pattern and intensity varying within different histological subtypes, being greater the more aggressive the tumor subtype. Conclusions. Bcl-2 and c-kit are not useful as immunohistochemical markers in differentiating adenoid cystic carcinoma from polymorphous low-grade adenocarcinoma.