Impact of γ-herpes viruses’ status on established risk factor profile of oral squamous cell carcinoma tissues in a group of Sri Lankan male

Abstract

ABSTRACTOral cancer with multifactorial aetiology was established as a public health challenge globally especially locally. Alarmingly, oral cancer ranks 1st among Sri Lankan males and 8thamong Sri Lankan females with 2-3 death daily. Oral squamous cell carcinoma (OSCC) accounts for 90-95% of oral malignancies in most countries. Perhaps, infectious agents are responsible for approximately 20% of global cancer incidence. Among them, Epstein-Barr virus (EBV) and Kaposi’s sarcoma-associated herpes virus (KHSV) are γ-herpes viruses linked with mucosal malignancies also. There is a dearth of information on oncogenic viral infections in oral cancer patients. Thus, the present study aimed to investigate the impact of γ-herpes viruses’ status on the -established risk factor profile of OSCC tissue in a group of Sri Lankan male patients. Ethical approvals were obtained from Sri Lanka and Australia. A large unmatched case-control study was conducted on Oral and Maxillo-Facial Surgical (OMF) units located in six provinces. Consequently, a representative sub-sample of histopathologically confirmed 29 OSCC cases and clinically diagnosed 25 Fibroepithelial-poly (FEP)controls was selected from the main, adhering to stringent inclusion criteria, for cases at least with betel quid chewing, while excluding none of oral risk habits. Incisional biopsies of cases and excisional biopsies of controls were collected, transported, stored, and dispatched as frozen tissues at - 800C. Then, DNA was extracted from frozen specimens. Subsequently, real-time PCR was performed to detect γ-herpes viruses separately. Socio demographic and clinical data were obtained entered and analysed using SPSS-21 Statistical Package. Descriptive statistics and Fisher’s exact test were used to compare groups ((cell counts <5). The overall EBV prevalence was calculated as 34 (64.2%). In OSCC cases the EBV positivity was higher 21(77.8%) than the FEP controls 13 (50.0%), and this difference was statistically significant (p<0.05). Neither cases nor controls infected with KSHV/HHV-8. In oral risk habit comparison, the cases were better substance abusers, especially in terms of betel quid chewing and alcohol consumption than the control group (p<0.05), The impacts of γ-herpes viruses’ status on established risk factors are noteworthy to investigate by adequately powered prospective studies exclusively in local and regional context.