What are the implications of human papillomavirus status in oropharyngeal tumors for clinical practice? Curr Opin Otolaryngol Head Neck Surg. 2014;22:90-94. [PMID: 24492854 DOI: 10.1097/moo.0000000000000030]

HPV infection and P16 expression in oral and oropharyngeal cancer in Kazakhstan

Background

Human papillomavirus (HPV) is an important etiologic factor in different cancers of anogenital region and also in a fraction of head and neck cancers (HNC) particularly oropharyngeal tumors. The HPV16 genotype associated with the majority of HPV-related head and neck carcinomas. Th incidence of oropharyngeal cancer is increasing in many countries, and the rate of HPV positive tumors is about 70% in Europe and North America. Little known about the prevalence of HPV in HNC in Central Asia.

Methods

It’s a prospective analysis of patients with verified oral or oropharyngeal cancer. Sociodemographic and clinical data obtained on admission to treatment. The diagnosis of HPV positivity assessed by both the P16 expression on immunohistochemistry(IHC) and polymerase chain reaction (PCR)with HPV DNA detection and HR HPV type determination.

Results

Seventy six patients with oral and oropharyngeal cancer tested for HPV. Forteen cases were positive for HPV by PCR and 15 cases by P16 IHC. Of the 35 oropharyngeal tumors, nine were HPV DNA and p16 IHC positive, giving the rate of 25.7%. Of the 41 oral tumors, five were HPV DNA and six p16 IHC positive, giving the rate of 12.2%.

Conclusion

It is the first study mapping prevalence of HPV positivity in oral and oropharyngeal cancer in the Central Asian region. The rate of HPV positivity was higher in oropharyngeal than in oral cancer, the nonsmokers were significantly more frequent in the HPV positive group and HPV 16 was the most frequent type. However, the HPV positivity rates are lower than referred in the western world.

Is treatment de-escalation a reality in HPV related oropharyngeal cancer?

The incidence of HPV related oropharyngeal squamous cell carcinoma (OPSCC) is rapidly increasing. It is now well recognised as a distinct clinical and biologic entity, compared to traditional OPSCC. The majority of these patients have an excellent prognosis due to the chemo-radiosensitive nature of these tumours. The de-escalation of current treatment regimens have therefore been proposed in an attempt to reduce the long term treatment related morbidity of this much younger patient cohort. Several of the more pertinent points regarding safe de-escalation strategies are considered within this manuscript.

E1 detection as prognosticator in human papillomavirus-positive head and neck cancers

PURPOSE

HPV-related locally advanced head and neck cancers (LA-HNCs) show a good prognosis. This study aimed to investigate the HPV prevalence in LA-HNCs and compare the prognostic value of E1, E6 and L1 genomic viral fragments and p16, individually and in combination, in order to find the best prognosticator in terms of overall survival (OS) and progression-free survival (PFS).

PATIENTS AND METHODS

HPV16 was searched in 255 LA-HNC formalin-fixed paraffin-embedded tumor tissues, 89 oropharyngeal cancers (OPCs), and 166 non-OPCs by DNA-PCR with 3 primer pairs. p16 was analyzed by immunohistochemistry in 235 patients.

RESULTS

The prevalence of positive samples decreased constantly from E6 to L1 and E1 in both OPCs and non-OPCs. Each LA-HNC patient highlighted variable positivity for each fragment. OPCs showed a higher prevalence of positive samples compared to non-OPCs.Positive coexistence of all the fragments was more common in OPCs (31.5%) than non-OPCs (4.2%), and E1 detection was always associated with E6 and L1. E1-positive OPCs showed improved OS (p = 0.012) and PFS (p = 0.036), while L1- or E6-positive ones did not. p16-positive patients were more prevalent in the OPC (29.8%) than the non-OPC group (7.3%) (p<0.0001) and its prognostic value was not superior to that of E1. However, the multivariate Cox analysis which included E1, L1, E6 status and p16 expression did not show a significant p value.

CONCLUSIONS

Though HPV16 positivity measured by DNA-PCR was higher for L1 and E6, they performed weakly as prognosticators; E1 might become a strong prognostic marker for OS and PFS in OPCs.

Role of human papillomavirus in oropharyngeal squamous cell carcinoma: A review

Human papillomavirus (HPV) has been implicated in the pathogenesis of a subset of oropharyngeal squamous cell carcinoma. As a result, traditional paradigms in relation to the management of head and neck squamous cell carcinoma have been changing. Research into HPV-related oropharyngeal squamous cell carcinoma is rapidly expanding, however many molecular pathological and clinical aspects of the role of HPV remain uncertain and are the subject of ongoing investigation. A detailed search of the literature pertaining to HPV-related oropharyngeal squamous cell carcinoma was performed and information on the topic was gathered. In this article, we present an extensive review of the current literature on the role of HPV in oropharyngeal squamous cell carcinoma, particularly in relation to epidemiology, risk factors, carcinogenesis, biomarkers and clinical implications. HPV has been established as a causative agent in oropharyngeal squamous cell carcinoma and biologically active HPV can act as a prognosticator with better overall survival than HPV-negative tumours. A distinct group of younger patients with limited tobacco and alcohol exposure have emerged as characteristic of this HPV-related subset of squamous cell carcinoma of the head and neck. However, the exact molecular mechanisms of carcinogenesis are not completely understood and further studies are needed to assist development of optimal prevention and treatment modalities.