High Serum Level of Retinol and α-Tocopherol Affords Protection Against Oral Cancer in a Multiethnic Population

Background: A comparative cross-sectional study involving oral cancer patients and healthy individuals wasdesigned to investigate associations between retinol, α-tocopherol and β-carotene with the risk of oral cancer.Materials and
Methods: This study included a total of 240 matched cases and controls where subjects wereselected from the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). Retinol, α-tocopheroland β-carotene levels and intake were examined by high-performance liquid chromatography (HPLC) and foodfrequency questionnaire (FFQ) respectively.
Results: It was found that results from the two methods applied didnot correlate, so that further analysis was done using the HPLC method utilising blood serum. Serum levels ofretinol and α-tocopherol among cases (0.177±0.081, 1.649±1.670μg/ml) were significantly lower than in controls(0.264±0.137, 3.225±2.054μg/ml) (p<0.005). Although serum level of β-carotene among cases (0.106±0.159 μg/ml)were lower compared to controls (0.134±0.131μg/ml), statistical significance was not observed. Logistic regressionanalysis showed that high serum level of retinol (OR=0.501, 95% CI=0.254-0.992, p<0.05) and α-tocopherol(OR=0.184, 95% CI=0.091-0.370, p<0.05) was significantly related to lower risk of oral cancer, whereas norelationship was observed between β-carotene and oral cancer risk.
Conclusions: High serum levels of retinoland α-tocopherol confer protection against oral cancer risk.