A quantitative investigation of immunocytochemically stained blood vessels in normal, benign, premalignant and malignant human oral cheek epithelium

Abstract

The present study was designed to determine whether increased vascularity occurs during malignant transformation of human oral cheek epithelium. Nine normal (N) samples were taken from the resection margins of benign lesions; the pathological lesions were classified as chronic inflammation (CI; n = 11), fibrous hyperplasia (FH; n = 12), lichen planus (LIP; n = 8), dysplasia (DYS; n = 5), squamous cell carcinoma (SCC; n = 25; well differentiated [SCCWD]; n = 10; moderately to poorly differentiated [SCCMPD]; n = 15) and epithelium adjacent to carcinomas (EAC; n = 6). Sections were stained with monoclonal antibody (mAb) against vimentin using an ABC immunoperoxidase technique. All blood vessels present within a depth of 0.9 mm of lamina propria were quantified irrespective of their morphology. The blood vessel parameters quantified were volume density (V(VBV, CT)), number per unit area (N(ABV, CT)), length per unit volume (L(VBV, CT)) and mean transverse sectional area (A(BV)). V(VBV, CT) increased significantly between normal and all pathological groups. Amongst the pathological groups, statistical differences were detected between CI and SCC, CI and EAC, FH and SCCWD, FH and EAC, LIP and SCC, LIP and EAC, DYS and SCCWD and DYS and EAC. The EAC group had the highest V(VBV, CT) and the values of N(ABV, CT) and L(VBV, CT) were significantly higher in all the pathological groups when compared with the normal group. No significant differences were detected between any of the pathological group. The parameter ABV increased significantly between normal and DYS, FH, SCC, EAC, FH and EAC, FH and SCC, CI and EAC, CI and SCC, LIP and EAC and LIP and SCC. Spearman rank correlations detected a positive correlation between the severity of oral lesions and all of the blood vessel parameters. We conclude that a mAb against vimentin improved the identification of smaller blood vessels and the blood vessel data suggest that angiogenesis occurs in premalignant and malignant lesions of human oral cheek epithelium. Angiogenesis seems to play an essential role in sustaining the actively growing and transforming cells.