Salivary lactate dehydrogenase as a prognostic marker in oral squamous cell carcinoma patients following surgical therapy.

Objective: The objective of the present study was to assay the salivary levels of lactate dehydrogenase in patients with OSCC in comparison to healthy controls and to assess the changes in salivary levels of lactate dehydrogenase as prognostic markers of surgical therapy in oral squamous cell carcinoma patients. A case control study was undertaken comprising of 20 patients who were clinically diagnosed and histopathologically proven with oral squamous cell carcinoma and compared with 20 age and gender matched controls. Unstimulated whole saliva (2 ml) was collected by the spit method from every subject. The salivary LDH levels were analysed before surgery (baseline value) and compared with the control group. One month following surgical therapy, the salivary LDH levels were measured again and compared with the baseline values. The results obtained were subjected to statistical analysis using one way ANOVA and Pearson's correlation. The results of the present study showed that the mean salivary LDH levels in the study and control group were 457.06 ± 88.93 IU/L and 178.35 ± 120.54 IU/L respectively, the difference of which was statistically significant (p<0.001). Comparison of salivary LDH levels before surgery and 1 month after surgery showed that there was a decrease of salivary LDH levels, one month after surgical therapy, the difference of which was statistically significant (p<0.001). The study concluded that salivary lactate dehydrogenase levels could be used not only as a diagnostic marker but it could also be a valuable prognostic biomarker in patients treated surgically for OSCC.