Background: Oral precancerous lesions are potentially malignant disorders that carry a high risk of transformation into oral cancer if not detected early. Conventional diagnostic methods rely on invasive biopsies, highlighting the need for reliable, non-invasive biomarkers. Salivary malondialdehyde (MDA), interleukin-6 (IL-6), and lactate dehydrogenase (LDH) reflect oxidative stress, inflammation, and tissue injury, respectively, and may serve as valuable diagnostic tools. Objectives: To measure and compare salivary levels of MDA, IL-6, and LDH between patients with oral precancerous lesions and individuals without such lesions, and to assess their diagnostic potential. Methods: A case-control study was conducted at the Oncology Center, Medical City, Baghdad, Iraq, between August 2024 and March 2025. A total of 102 participants were enrolled: 54 patients with clinically and histopathologically confirmed oral precancerous lesions and 48 lesion-free controls. Unstimulated saliva samples were collected under standardized conditions and analyzed for MDA, IL-6, and LDH levels using validated biochemical methods. Statistical analyses, including ROC curve evaluation, were performed to assess diagnostic accuracy. Results: Patients with oral precancerous lesions exhibited significantly higher salivary concentrations of MDA, IL-6, and LDH compared to negative cases (p < 0.05). ROC analysis demonstrated good diagnostic performance for all three biomarkers, with IL-6 showing the highest area under the curve, followed by MDA and LDH. No significant gender-based differences were observed in biomarker expression. Conclusion: Elevated salivary levels of MDA, IL-6, and LDH are strongly associated with oral precancerous lesions, suggesting their utility as non-invasive biomarkers for early detection. Incorporating these salivary assays into routine screening may facilitate timely intervention and reduce the progression to oral cancer.
Ghufran Salman Abd Alhussain (Thu,) studied this question.