Morphometric analysis in potentially malignant head and neck lesions: oral submucous fibrosis

The objective of this study is to analyze cases of oral submucous fibrosis (OSMF) Grade I, II, III and IV morphometrically with regard to epithelium, vasculature and fibrosis and determine any correlation with histological grading after Pindborg and Sirsat.

Eighty three oral submucous fibrosis cases were analyzed morpometrically using an interactive image analysis system in the Department of Pathology, M.L.N Medical College, Allahabad, U.P, India. Paraffin embedded sections of 3-4 microm thickness were stained with hematoxylin/eosin, Van Gieson's picric acid and acid fuchsin stain and Masson's trichrome stains. Image analysis was performed with specific software (Image Pro Plus 6.0) and data obtained were finally transported to Excel sheets for calculation of average values for each parameter.

With the grading criteria applied, 9 cases of OSMF were grade I, 32 grade II, 39 grade III and 3 grade IV. Clinical trismus was most frequent in Grade IV followed by Grade III, II and I respectively. OSMF Grade I cases did not show any measurable amount of collagenization, whereas it showed a significant increase with OSMF I and II grades [Pearson's chi2 test= 85.72; p= 0.051] and OSMF-III and IV [Pearson's chi2 test=188.74; p<0.001]. Numbers of endothelial cells per low power field consistently decreased with the increasing grade.

We concluded that mean blood vessel area and the mean vessel diameter showed a marked increase in grade II and a marker decrease in grade IV and the grade III, collagen thickness (mum) increases according to increasing grade while density of endothelial cells decreases.