Tobacco is the major etiological factor for
oral cancer development through the generation of oxidative stress. Therefore, markers of oxidative stress such as total
antioxidant status, lipid peroxidation, and total
thiol levels might be useful to monitor oxidative stress and predict overall survival in
oral cancer patients. The study included 140
oral cancer patients and 50 healthy controls, who were classified as with the habit of tobacco and no habit of tobacco. Adjacent normal and malignant tissue samples were collected from
oral cancer patients. Plasma and tissue levels of lipid peroxidation,
thiol, and total
antioxidant status were assayed by spectrophotometric methods.
Thiol levels were significantly lower in controls with the habit of tobacco (P= .033),
oral cancer patients (P= .0001), and malignant tissues (P= .015) as compared to controls with no habit of tobacco, controls with the habit of tobacco, and adjacent normal tissues, respectively. Tobacco exposure was higher in
oral cancer patients than controls with the habit of tobacco. Controls with the habit of tobacco who had lower
thiol (odds ratio [OR]=10.58, P= .008) and high tobacco exposure (OR=0.251, P= .05) showed an elevated risk of
oral cancer development. Patients showing a lipid peroxidation level above the cutoff level as compared to patients below the cutoff level showed poor overall survival, whereas those with
thiol and total
antioxidant status levels below the cutoff level as compared to their respective counterparts showed poor overall survival. In conclusion, lipid peroxidation and
thiol could be useful for predicting the risk of oral
carcinogenesis in healthy tobacco consumers and predicting overall survival of
oral cancer patients.