HPV in oral squamous cell carcinoma vs head and neck squamous cell carcinoma biopsies: a meta-analysis (1988-2007)

Role of human papillomavirus and its detection in potentially malignant and malignant head and neck lesions: updated review

Head and neck malignancies are characterized by a multiphasic and multifactorial etiopathogenesis. Tobacco and alcohol consumption are the most common risk factors for head and neck malignancy. Other factors, including DNA viruses, especially human papilloma virus (HPV), may also play a role in the initiation or development of these lesions. The pathways of HPV transmission in the head and neck mucosal lesions include oral-genital contact, more than one sexual partner and perinatal transmission of HPV to the neonatal child. The increase in prevalence of HPV infection in these lesions may be due to wider acceptance of oral sex among teenagers and adults as this is perceived to be a form of safe sex. The prevalence of HPV in benign lesions as well as malignancies has been assessed by many techniques. Among these, the polymerase chain reaction is the most sensitive method. Review of literature reveals that HPV may be a risk factor for malignancies, but not in all cases. For confirmation of the role of HPV in head and neck squamous cell carcinoma, large population studies are necessary in an assortment of clinical settings. Prophylactic vaccination against high-risk HPV types eventually may prevent a significant number of cervical carcinomas. Of the two vaccines currently available, Gardasil (Merck & Co., Inc.) protects against HPV types 6, 11, 16 and 18, while the other vaccine, Cervarix (GlaxoSmithKline, Rixensart, Belgium) protects against HPV types 16 and 18 only. However, the HPV vaccine has, to the best of our knowledge, not been tried in head and neck carcinoma. The role of HPV in etiopathogenesis, prevalence in benign and malignant lesions of this area and vaccination strategies are briefly reviewed here.

[Human papillomavirus and cancer of the oropharynx. Molecular interaction and clinical implications]

One-third of the cases of oropharyngeal squamous cell carcinoma (OSCC) contain oncogenic human papillomavirus (HR-HPV). Epidemiologic and molecular evidence underlines the causal role of HR-HPV in these tumors, which can be defined as HPV-related OSCC. These tumors differ from chemical/toxin-induced OSCC in several biological aspects, including specific molecular and genetic alterations. This leads to a characteristic clinical profile of HPV-related OSCC. Sexual risk factors play a role; however, the knowledge about natural infection and the rate of persistence of HR-HPV in the oropharynx is marginal. It is shown that the distinct biological behavior of the HPV-related subset of oropharyngeal tumors results in a more favorable prognosis. This might be the result of a better response to chemotherapy and radiotherapy. However, further studies are needed to show whether it will be possible to reliably select patients for individualized therapy depended on the HPV status of their tumors. Therefore, we think it will be mandatory to consider and stratify HPV status in the design of prospective clinical trials in the future.

Association between human papillomavirus and Epstein-Barr virus infections in human oral carcinogenesis

Infection by high-risk human papillomaviruses (HPVs) and Epstein-Barr virus (EBV) are very frequent in the adult human population, and have been associated with several human carcinomas, especially oral cancers. However, a small number of studies have examined the association between high-risk HPV and EBV in the progression of human oral cancers. Currently, the role of high-risk HPV and EBV co-infections in human oral cancers, particularly nasopharyngeal carcinomas, remain uncertain because of the limited number of investigations. This raises the question whether high-risk HPV and EBV co-infections play a significant role in the development of human nasopharyngeal carcinomas. In this paper, we propose the hypothesis that human oral normal epithelial cells, especially nasopharyngeal cells, are very susceptible to persistent HPV and EBV co-infections; therefore, high-risk HPV and EBV co-infections play an important role in the initiation of a neoplastic transformation of human oral epithelial cells. We believe that significant studies, using different cells and animal models as well as clinical samples, are necessary to answer these important questions.

Controversies surrounding human papilloma virus infection, head & neck vs oral cancer, implications for prophylaxis and treatment

Head & Neck Cancer (HNC) represents the sixth most common malignancy worldwide and it is historically linked to well-known behavioural risk factors, i.e., tobacco smoking and/or the alcohol consumption. Recently, substantial evidence has been mounting that Human Papillomavirus (HPV) infection is playing an increasing important role in oral cancer. Because of the attention and clamor surrounding oral HPV infection and related cancers, as well as the use of HPV prophylactic vaccines, in this invited perspective the authors raise some questions and review some controversial issues on HPV infection and its role in HNC, with a particular focus on oral squamous cell carcinoma.

The problematic definition and classification of HNC will be discussed, together with the characteristics of oral infection with oncogenic HPV types, the frequency of HPV DNA detection in HNC, the location of HPV-related tumours, the severity and prognosis of HPV-positive HNC, the diagnosis of oral HPV infection, common routes of oral infection and the likelihood of oro-genital HPV transmission, the prevention of HPV infection and novel therapeutic approaches.

Is there an optimal chemotherapy regimen for the treatment of advanced gastric cancer that will provide a platform for the introduction of new biological agents?

Globally, gastric cancer is the second most common cause of cancer-related death. The majority of gastric cancer patients will have at presentation or will ultimately develop overt metastatic disease. Meta-analysis has demonstrated not only that systemic chemotherapy can improve survival in patients with advanced disease but also that the best survival results in earlier randomized studies have been achieved with three-drug regimens containing a fluoropyrimidine, an anthracycline, and cisplatin. Although there has been little progress historically in improving median overall survival times beyond the 9-month plateau achievable with the standard epirubicin-cisplatin-infusional 5-fluoropyrimidine (ECF) combination, the availability of newer cytotoxic anticancer agents has provided some measure of optimism that current outcomes can be improved. A number of new triplet and doublet combinations incorporating docetaxel, oxaliplatin, irinotecan, capecitabine, and S-1 have been explored in randomized trials. Although some combinations, such as epirubicin-oxaliplatin-capecitabine, have been shown to be as effective as (or perhaps more effective than) ECF, and although promising early data have been derived for S-1 in combination with cisplatin, a lack of studies in which direct comparisons have been made currently hinders the identification of the optimal regimen in this setting. One factor that might contribute to the lack of clear progress is the absence of consensus on the utility of second-line cytotoxic treatments. It can therefore be concluded that, although there is no first-line regimen that is clearly the most appropriate platform for the investigation of biological agents, there are a number of combinations that have been shown to be effective and therefore good candidates.