Antiviral therapy against chronic hepatitis C is associated with a reduced risk of oral cancer

The Role of Oncogenic Viruses in Head and Neck Cancers: Epidemiology, Pathogenesis, and Advancements in Detection Methods

Head and neck cancers (HNCs) constitute a wide range of malignancies originating from the epithelial lining of the upper aerodigestive tract, including the oral cavity, pharynx, larynx, nasal cavity, paranasal sinuses, and salivary glands. Although lymphomas affecting this region are not conventionally classified as HNCs, they may occur in lymph nodes or mucosa-associated lymphoid tissues within the head and neck. Oncogenic viruses play a crucial role in HNC onset. Human papillomavirus (HPV) is extensively studied for its association with oropharyngeal cancers; nevertheless, other oncogenic viruses also contribute to HNC development. This review provides an overview of the epidemiology, pathogenesis, and advancements in detection methods of oncogenic viruses associated with HNCs, recognizing HPV's well-established role while exploring additional viral connections. Notably, Epstein-Barr virus is linked to nasopharyngeal carcinoma and lymphomas. Human herpesvirus 8 is implicated in Kaposi's sarcoma, and Merkel cell polyomavirus is associated with subsets of HNCs. Additionally, hepatitis viruses are examined for their potential association with HNCs. Understanding the viral contributions in the head and neck area is critical for refining therapeutic approaches. This review underlines the interaction between viruses and malignancies in this region, highlighting the necessity for ongoing research to elucidate additional mechanisms and enhance clinical outcomes.

Is Systemic Immunosuppression a Risk Factor for Oral Cancer? A Systematic Review and Meta-Analysis

Even if the relationship between immunosuppression and increased incidence of systemic cancers is well known, there is less awareness about the risk of developing oral cancer in immunosuppressed patients. The aim of this review was to evaluate the association between immunosuppression and the development of oral cancer. Two authors independently and, in duplicate, conducted a systematic literature review of international journals and electronic databases (MEDLINE via OVID, Scopus, and Web of Science) from their inception to 28 April 2023. The assessment of risk of bias and overall quality of evidence was performed using the Newcastle-Ottawa Scale and GRADE system. A total of 2843 articles was identified, of which 44 met the inclusion criteria and were included in either the qualitative or quantitative analysis. The methodological quality of the included studies was generally high or moderate. The quantitative analysis of the studies revealed that immunosuppression should be considered a risk factor for the development of oral cancer, with a percentage of increased risk ranging from 0.2% to 1% (95% CI: 0.2% to 1.4%). In conclusion, the results suggest that a constant and accurate follow-up should be reserved for all immunosuppressed patients as a crucial strategy to intercept lesions that have an increased potential to evolve into oral cancer.

Effects of Hepatitis C Virus Elimination by Direct-Acting Antiviral Agents on the Occurrence of Oral Lichen Planus and Periodontal Pathogen Load: A Preliminary Report

Objective

The association between hepatitis C virus (HCV) and oral lichen planus (OLP) is well known, but the association with periodontal disease has been reported less often. The purpose of this study was to investigate the effects of periodontal bacteria and OLP lesions before and after HCV elimination. Subjects and Methods. The subjects were four OLP patients (mean age 72.5 years) with HCV infection. Six types of periodontal bacteria (Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Fusobacterium nucleatum) were quantified in saliva, and changes in OLP were examined before and after elimination of HCV by antiviral therapy. Biochemical blood tests also were performed.

Results

The total number of periodontal bacteria, the numbers of P. gingivalis, T. forsythia, T. denticola, and F. nucleatum, and the risk of presenting with the red-complex bacteria (P. gingivalis, T. forsythia, and T.denticola), leading to periodontal disease progression, decreased after HCV elimination. OLP disappeared in three of the four patients and decreased in the other after sustained virological responses (SVRs).

Conclusion

HCV elimination not only improved OLP lesions but also reduced the number of periodontal pathogens and the amount of red-complex periodontal pathogens.

Hepatitis C Virus RNA Transcript Associates with Prognosis in Non-human Papillomavirus Associated Head and Neck Squamous Cell Carcinoma

OBJECTIVE/HYPOTHESIS

Hepatitis C virus (HCV) was reported to associate with head and neck squamous cell carcinoma (HNSCC) in many studies. However, its correlation with prognosis of non-human papillomavirus (HPV) associated HNSCC remains unknown. Here, we sought to investigate clinical significance of HCV RNA transcript in non-HPV associated HNSCC by analyzing corresponding RNA-seq data.

STUDY DESIGN

A retrospective cohort study.

METHODS

Four hundred and forty-eight non-HPV associated HNSCC patients with aligned RNA-seq and clinical follow-up data were included and divided into two groups: low-HCV and high-HCV. Means of continuous variables and proportions of categorical variables were compared using independent sample t-test and chi-square test, respectively. Survival data were compared using Cox regression analysis, Kaplan-Meier curves, and log-rank test. Expression of genome-wide mRNAs and abundance of immune cells were compared using volcano plot and cell signature estimated score analysis.

RESULTS

HCV RNA transcript negatively correlates with pathologic (P = .028) and clinical-stage (P = .023), clinical N stage (P = .025), and nodal extracapsular spread (P = .042) and is an independent prognosis factor in non-HPV associated HNSCC (HR = 1.488; 95% CI: 1.004-2.206; P = .048). Elevated expression of HCV improved 5-year overall survival (43.6% vs. 53.2%; P = .035) in all non-HPV associated HNSCC patients, the same as in male (46.6% vs. 58.7%; P = .049), clinical M0 stage (42.8% vs. 52.9%; P = .036), white (42.9% vs. 55.9%; P = .010), and histologic grade 1 to 2 subgroups (42.1% vs. 57.2%; P = .043). The expression of several immune-related genes and abundance of some immune cells significantly changed with the increase of HCV RNA transcript, while HCV-related oncogenes and tumor suppressor gene did not.

CONCLUSIONS

HCV RNA transcript is an independent favorable factor for prognosis of non-HPV associated HNSCC.

LEVELS OF EVIDENCE

4 Laryngoscope, 131:1774-1781, 2021.

The role of dentists in controlling hepatocellular carcinoma in Japan (Review)

In Japan, the method of treatment for hepatitis is well established due to the high rates of hepatitis C. However, the identification of patients with hepatitis who do not receive appropriate treatment poses a major problem. Some patients with this disease may need to consult with a dentist due to the development of extrahepatic manifestations, such as lichen planus, in the oral cavity. Alternatively, the dentist might discover patients with untreated hepatitis C and hepatitis B during routine dental examination. In such cases, the patient should be referred to a hepatologist for further examinations and treatment. Thus, dentists are required to act as 'gatekeepers of hepatitis'. Furthermore, Japanese dentists need to increase hepatitis B vaccine coverage for infection control. By acting as a 'care coordinator of hepatitis', the dentist will be able to contribute to the eradication of liver cancer in Japan, thereby eliminating the discrimination and prejudice against patients with hepatitis. Dentists need to have a deep understanding of liver disease from the viewpoints of both nosocomial infection control and treatment of oral diseases.