Salivary Lactate Dehydrogenase - A Biomarker of Potentially Malignant and Malignant Diseases of Oral Cavity?

Introduction: Oral cancer is the sixth most common cancer occurring worldwide. In many cases, cancer develops from the site of potentially malignant lesion. Lactate dehydrogenase (LDH) is an ubiquitous enzyme the level of which is known to increase in serum and saliva as a result of shift of glycolytic pathway from aerobic to anaerobic in dysplastic cells.

Aim: This study aims to emphasize salivary LDH as a reliable bio-marker in diagnosing potentially malignant and malignant diseases.

Materials and Methods: Forty patients from the department of Oral Medicine and Radiology were enrolled in the study and divided into 2 groups: Group I consisting of patients with oral leukoplakia, oral submucous fibrosis and oral carcinoma; Group II consisting of healthy controls. Unstimulated saliva of about 2 ml was collected from all patients. LDH level in saliva was estimated using semi-automatic analyzer and LDH (P-L) kit. The obtained values were tabulated and statistical results were obtained.

Results: The mean salivary lactate dehydrogenase level was higher in case group than control group with value of 962.8 U/l in case group and 398.1 U/l in control group. There was statistically significant difference between the mean salivary LDH levels of the above groups.

Conclusion: This study concludes that Salivary LDH estimation can be used as an efficient, non‑invasive, cost effective and friendly new tool for diagnosis of patients with oral potentially malignant and malignant diseases.