Immunohistochemical expression of CD34 and basic fibroblast growth factor (bFGF) in oral submucous fibrosis

Oral submucous fibrosis (OSMF) is an insidious chronic fibrotic condition that involves the oral mucosa and occasionally the pharynx and esophagus. Vascularity in OSMF has always been a matter of debate. The prevailing concept is that epithelial atrophy occurs due to lack of perfusion but the recent data challenges this concept. Therefore, the present study was conducted to evaluate the immunoreactivity of CD34 and basic fibroblast growth factor (bFGF) in different histological grades of OSMF. This might further shed light to the role of microvasculature in OSMF, so that the epithelial atrophy and resultant malignant transformation seen in the advanced stages might be elucidated.

A total of 30 cases of OSMF were included in the study and mean vascular density (MVD) was calculated using CD34 and bFGF. Five cases of OSMF with dysplasia and 2 cases of OSMF turning malignant were added during the course of the study.

Mean vascular density was found to decrease significantly as the diseases advanced. Furthermore, vascularity increased significantly in cases of OSMF turning towards malignancy.

Our study supports the concept of epithelial atrophy aftermath of lack of perfusion. There is reduced vascularity as the disease advances and this denies the systemic absorption of carcinogens, which affects the already compromised epithelium. Consequently, liberation of angiogenic factors occurs because of malignant transformation, which explains the neoangiogenesis and increased vascularity in OSMF turning towards malignancy. Further studies are required to identify the mechanism leading to carcinogenesis in the atrophied epithelium aftermath of fibrosis and decreased vascularity.