Vascular endothelial growth factor ( VEGF) expression and microvascular density in salivary gland tumours

This study investigates whether salivary tumours with different morphology and evolution also differ in terms of neovascularization and VEGF expression and the prognostic value of the results. Surgical specimens from 45 patients - 8 pleomorphic adenomas (PA), 7 Warthin tumours (WT), 5 basal cell adenomas (BA), 6 carcinomas ex-pleomorphic adenoma (CEPA), 6 mucoepidermoid carcinomas (MEC), 5 acinic cell carcinomas (AC), 4 adenoid cystic carcinomas (ACC) and 4 adenocarcinomas not otherwise specified (ADK NOS) - were immunostained. In malignant salivary tumours, the following mean microvascular density (MVD) values were recorded (+/- SD=Standard Deviation): 27.61 (SD +/- 2.27) in cases with CEPA, 27.08 (DS +/- 7.81) in AC and 32.93 (SD +/- 7.76) in ADK NOS, with lower values for MEC 24.31(SD +/- 2.88) and for ACC 22.13 (SD +/- 5.44). For benign tumours, an MVD of 35.71 (SD +/- 2.09) was recorded in WT and lower average values in PA (MVD=14.84; SD +/- 4.86) and in BA (MVD=23.96; SD +/- 9.13). MVD did not correlate with the investigated clinicopathological parameters. The VEGF expression is significantly more important (p=0.001) in malignant salivary tumours as compared with benign ones. The VEGF expression and the microvascularization in salivary gland tumours are important elements to be considered when formulating a diagnosis and assessing case evolutions in patients with such tumours.