K.C. Chiu*, L.C. Chang, S.H. Li, H.C. SU, J.Y. Lee, and Y.S. Shieh# School of Dentistry, National Defense Medical Center; Department of Dentistry, Tri-Service General Hospital; Department of Dentistry, Army Force Taichoun Hospital.

       We investigated the processes of angiogenesis, cell proliferation, and apoptosis in mucoepidermoid carcinoma (MEC) and their value in predicting the tumor behavior of MEC. CD34, Ki-67, and caspase-3 immunohistochemical staining and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) were evaluated retrospectively in 41 MEC patients. The correlations between these measures and the clinical–pathological features were investigated. The peritumoral and intratumoral microvessel density (MVD) was 29.5 ± 10.4 and 19.5 ± 7.1, respectively. Intratumoral MVD was correlated with tumor stage. In cancer tissues, the mean proliferation index (PI) was 11.7% ± 5.9% and the mean apoptotic index (AI) was 4.1% ± 2.3%. The PI was significantly correlated with tumor grade, and the PI/AI ratio was significantly correlated with tumor size and stage. Fewer tumor samples were positive for caspase-3 expression (14/41, 44%) than were negative (23/41, 56%). Caspase-3 expression was significantly correlated with clinical stage and was inversely correlated with PI. Our data suggest that intratumoral MVD, the PI/AI ratio, and caspase-3 expression are potentially useful markers of tumor progression in patients with MEC.