Differences in oral habit and lymphocyte subpopulation affect malignant transformation of patients with oral precancer

Background/purposeIn Taiwan, the combination of betel quid chewing, alcohol consumption, and smoking habits increases oral cancer risk by 123-fold compared to persons without these habits. Lymphocyte populations in patients may potentially affect the malignant transformation of oral precancer.MethodsA total of 28 patients with oral precancer from our previous cohort were enrolled in this study, and their personal information and oral habits were documented. Their lymphocyte populations (CD4+, CD8+, CD19+, and CD56+) and activation markers (CD25 and CD69) were determined by flow cytometry from 1999 to 2004. After follow up till December 2014, data of patients with/without malignant transformation were recorded, and the relation between oral habits and percentage of initial lymphocyte markers was evaluated using the Student t test and Fisher's exact test.ResultsTen precancer patients developed oral squamous cell carcinoma with a mean period of malignant transformation of 6.8 ± 2.1 years. Patients with malignant transformation had a mean age of 48.4 ± 5.0 years (n = 10), relatively more than that of patients without malignant transformation (41.6 ± 6.3 years, n = 18) (p < 0.05). An increase was noted in the population of peripheral blood mononuclear cells expressing CD4+CD69+, CD19+CD69+, and CD56+CD69+ (p < 0.05) in precancer patients with malignant transformation. Alcohol consumption showed an association with the malignant transformation of patients with precancer (p = 0.030), whereas betel quid and smoking showed little effect.ConclusionThese results suggest that age, alcohol consumption, and early activation of T cells, B cells, and natural killer cells are crucial in the malignant transformation of oral precancer. Analysis of patient's lymphocyte populations may help predict the malignant transformation of oral precancer.