RESUMO
In Pakistan, extensive use of several precarious chewable tobacco formulations has made oral cancer the second leading malignancy. Selection of literature was done by a survey of studies published from 1990 to 2017 mainly, from PUBMED and few from other search engines, on naswar, gutka, areca nut and betel quid, which included published reviews, original articles and other data sources on chewable tobacco, its epidemiology, pathological implications, and psychological effects. These studies have revealed that the chemicals in these formulations bind and mutate DNA of oral mucosa through down regulating cellular repair pathways and upregulating genetic networks associated with pathogenesis. Areca nut, having aercoline [the major alkaloid] causes carcinogenicity, mutagenicity, and genotoxicity of oral mucosa through increased production of growth factors and corticotrophin-releasing hormone, and genetic alteration in expression of CASP8, APAF-1, BAX, BAD, and upregulation of caspas-3. Gutka addiction leads to precancerous lesions resulting in characteristic facial abnormalities, following trismus. Naswar, in addition to oral cancer, causes adverse cardiovascular events by reducing glutathione per oxidase [GPx] and super-oxide dismutase [SOD], serum levels of HDL, whereas, increasing the ratio of cholesterol, LDL, triglycerides and LDL-C/HDL-C. Betel quid [Paan], causes psychoactivity affecting central and autonomic nervous systems leading to dependence with decreased cognition, euphoria, sweating, salivation, palpitation, heightened alertness and zest to work. Metabolically, cardio-acceleration, cortical desynchronisation of EEG, elevated plasma noradrenaline and adrenaline were found. This review highlights the corrosive effects of various most popular chewable tobacco formulations; and damage done by their cocktail of carcinogenic substances and added ingredients, leading to oropharangeal cancer
RESUMO
Background: Human Papilloma Virus [HPV] is found in the oral tobacco chewers with precancerous lesions such as submucous fibrosis [SMF], leukoplakia and erythroplakia. Trismus is a common symptom seen in patients with SMF and oral cancers. In Pakistan the risk of oral cancers has been raised up to 8.5 to 10 times due to increase in tobacco chewers in the recent years
Objective: To determine the frequency of oral HPV infection in chewable tobacco users with trismus living in the lowincome areas of Karachi
Methods: Camps were set up in 5 different areas of Karachi. In each camp, 100 people were examined for oral lesions by experienced volunteers. Oral rinse [40ml] was taken after gentle brushing over the lesions. DNA was extracted and PCR was performed using Gp5+/Gp6+ consensus primers. The results were analyzed on SPSS version 17.0
Results: Out of 187 subjects with trismus, 157 [84%] were males and 30 [15.51%] were females with average age of 28.7 years [12 -70 years]. Gutka, Naswar, Chalia and Paan users were 45.45%, 37.56%, 12.83% and 6.95% respectively. Mild trismus was found in 113 [60.43%] subjects followed by moderate trismus in 52 [27.81%] and severe trismus in 22[11.76%]. Out of total 36 [19%] HPV positive subjects, 27[14.44%], 7[3.74%] and 2[1.07%] had mild, moderate and severe trismus respectively. 150 controls tested negative for HPV
Conclusion: The frequency of HPV in oral cavity was high in subjects with trismus suggesting risk of oral squamous cell carcinoma. HPV in subjects with moderate to severe trismus should be tested in blood because it is difficult to get suitable oral sample