Non-invasive estimation of sialic acid in saliva among patients with oral potentially malignant disorders and oral cancer

Background: Oral potentially malignant disorders (OPMDs) account for about 2.5% of all the oral lesions, among which 37.5% show malignant transformation. Clinical appearances of any lesion which are deceived are finally confirmed and diagnosed using routine gold standard histological H and E stains. However, with newer technologies, cancer biomarkers in saliva are found to be highly sensitive. So, the early detection of cellular alterations at a non-lesional stage is of utmost importance to prevent its progression. Aim: To analyze the salivary sialic acid levels in the spectrum of patients having habits with no clinically visible lesion, leukoplakia, oral submucous fibrosis (OSMF) and oral squamous cell carcinoma (OSCC) along with the healthy groups and compare the levels with clinical and histological parameters. Materials and Methods: A total of 60 subjects were enrolled in this study. Sialic acid levels, total protein (TP) and total carbohydrate (TC) levels were estimated in saliva using appropriate biochemical analysis. Results: Results were analyzed using mean, standard deviation and Student's t test. Salivary sialic acid levels were significantly increased in leukoplakia, OSMF and OSCC. There is a significant difference in sialic acid levels in smokers and chewers yielding a mean value of 18.97 mg/dL and 23.4 mg/dL, respectively, against the mean value of 15.29 mg/dL of healthy controls. The sialic acid levels showed a statistical difference between clinical staging and histological grading of leukoplakia, OSMF and OSCC. Salivary sialic acid, protein and carbohydrate levels also showed significance. Conclusion: The present study highlights the altered expression of sialic acid among various groups suggesting that aberrant glycosylation in cell surface molecules during malignant transformation can give a clue on the tumor burden.