The Analysis of the Frequency of Leukoplakia in Reference of Tobacco Smoking among Northern Polish Population.

Objective: The aim of the study was an updated analysis of the frequency of leukoplakia in reference to tobacco smoking among the northern Polish population. Material and Methods: Medical records of 5720 patients who suffer from abnormalities and oral mucosa diseases between January 2015-December 2018 were analyzed. Among them, 416 medical charts of patients with leukoplakia were selected. The study group consisted of 196 women and 220 men aged between 21-86 years (average 45.6 years). The analysis was conducted in terms of age, gender, and smoking tobacco. The basic criterion for inclusion in the study was the presence of oral leukoplakia confirmed by histopathological examination, recorded in the chart. Information about the patient's active smoking was obtained from documented medical interviews. An active smoker was defined as a patient who smoked 10 or more cigarettes a day for at least the previous six months. The study used parametric and non-parametric statistical methods. Results: The highest incidence of leukoplakia was found in the age group 41-60 (46.6%), where the vast majority were active smokers (85.1%), and mostly men (86.2%). However, among patients with leukoplakia, the highest prevalence of smoking was found in the age group 21-40 years (86.8%) in women, where out of 38 patients with leukoplakia, 33 were active smokers. More patients with leukoplakia were observed in groups of smokers and it was statistically significant. Homogeneous form was the most commonly diagnosed form of leukoplakia in our study; it was found in almost 95% of cases. Leukoplakia was mainly observed on the cheeks. Changes on the gums, the alveolar process or the bottom of the tongue and mouth were rarely found. Conclusion: Our studies revealed that there is a statistically significant correlation between tobacco smoking and the presence of oral leukoplakia among the northern Polish population. It should be noted that dentists, in particular, are capable of early diagnosis and implementation of appropriate treatment of leukoplakia and, most often, crucial elimination of the main risk factor, which is smoking, and the implementation of effective tobacco control interventions.

[The relationship between methylation of p16 INK 4/CDKN2 gene in promoter region and progress of squamous cell carcinoma of buccal mucosa].

OBJECTIVE: To determine the correlation between methylation of p16 gene in promoter region and the carcinogenesis and progression of squamous cell carcinoma (SCC) of buccal mucosa. METHODS: Methylation of pl6 gene in SCC and leukoplakia of buccal mucosa was investigated by MSP and pl6 protein was analyzed by Western blot. RESULTS: The methylation of p16 gene was found in 15 of 30 cases SCC and 1 of 10 cases of leukoplakia of buccal mucosa (P < 0.05). Methylation of p16 gene in SCC of buccal mucosa was not related with age, sex, cell differentiation and clinical stage. But methylation of p16 in the cases with lymph node-metastasis was higher than that in the cases without lymph node-metastasis protein (P < 0.05). Meanwhile Methylation of p16 gene was positively correlated with no-expression of p16 protein (P < 0.01). CONCLUSIONS: The methylation of p16 gene leaded to the inactivation of p16 gene and was related with the carcinogenesis and progress of SCC of buccal mucosa.