Human papillomavirus expression and p53 gene mutations in squamous cell carcinoma

Global prevalence of human papillomavirus-related oral and oropharyngeal squamous cell carcinomas: a systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review to determine the global prevalence of HPV in oral squamous cell carcinoma (OSCC) and oropharyngeal squamous cell carcinoma (OPSCC).

MATERIALS AND METHODS

Literature was searched through October 2022 in main databases to address the question "What is the global prevalence of Human Papillomavirus in oral and oropharyngeal cancer?" Studies had to identify HPV by PCR, ISH, or p16 immunohistochemistry to be eligible. Quality was assessed using the JBI checklist for prevalence studies. Meta-analyses were performed, and reporting followed PRISMA guidelines.

RESULTS

Sixty-five studies were included, and most of them had methodological limitations related to sampling and the HPV detection tool. The pooled prevalence of HPV-positivity was 10% (event rate = 0.1; 95% CI: 0.07, 0.13; P < 0.01; I2 = 88%) in the oral cavity and 42% (event rate = 0.42; 95% CI: 0.36, 0.49; P = 0.02; I2 = 97%) in oropharynx. The highest HPV prevalence in OSCC was reached by Japan, meanwhile, in OPSCC, Finland and Sweden were the most prevalent. HPV16 is the genotype most frequent with 69% in OSCC and 89% in OPSCC, being the tonsils the intraoral location more affected by HPV (63%, p < 0.01, I2 76%).

CONCLUSION

The evidence points to an apparent burden in HPV-related OPSCC, mostly in North America, Northern Europe, and Oceania, especially due to the HPV16 infection suggesting different trends across continents.

CLINICAL RELEVANCE

This updated systematic review and meta-analysis provide sufficient evidence about the global HPV prevalence in OSCC and OPSCC and the most frequent HPV subtype worldwide.

Prognostic significance of human papillomavirus and Epstein-Bar virus in nasopharyngeal carcinoma

BACKGROUND

The clinical significance of Epstein-Barr virus (EBV) and human papillomavirus (HPV) infection in nasopharyngeal carcinoma (NPC) is unclear.

METHODS

Three hundred and forty three patients with NPC diagnosed between 1998 and 2017 and treated at our institution were included. Chi-square was used to identify characteristics associated with viral status. Kaplan-Meier methods were used to estimate overall survival (OS) and Cox proportional regression was used to identify prognostic factors.

RESULTS

Patients with HPV-associated NPC were more likely to have a positive smoking history and to present at a higher T classification. At a median follow-up time of 59.9 months (range: 0.1-222.4 months), there were no differences in OS (P = .198), time to local failure (LF, P = .403), or time to distant metastasis (DM, P = .849) between the viral subgroups. Older age (hazard ratio [HR]: 2.242, 95% confidence interval [CI] 1.374-3.659, P = .001) and higher overall stage (HR: 2.047, 95% CI 1.235-3.391, P = .005) were prognostic for worse OS.

CONCLUSION

In our population, viral status was not prognostic for OS, LF, or DM.

Human Papillomavirus, Smoking, and Cancer

Background:

The effect of smoking on human papillomavirus (HPV) activity and subsequent dysplasia and neoplasia remains controversial

Objective:

To determine any reported effects of smoking on either HPV activity or HPV-related dysplasia/cancer using retrospective analysis of the literature from 1966 through 1998 via Toxline and PubMed to search for “smoking,” “papillomavirus,” and “cancer.”

Conclusion:

Several recent large studies demonstrated that smoking was associated with a greater incidence of cervical, vulvar, penile, anal, oral, and head and neck cancer in a dose-dependent fashion, while other studies did not show any correlation between smoking and cervical dysplasia after multivariate adjustment. Recent studies have also indicated that smoking may be more closely related to high-grade lesions of the cervix and vulva. These data provide evidence of an association between HPV, smoking, and cancer. Progression of dysplasia likewise seems to be associated with smoking. Several groups have attempted to discern whether the connection between smoking and cervical cancer is from local immunosuppression and/or from direct carcinogenic effects.

Current relevance of hypoxia in head and neck cancer

Head and Neck cancer (HNC) is a complex mix of cancers and one of the more common cancers with a relatively poor prognosis. One of the factors that may assist us in predicting survival and allow us to adjust our treatment strategies is the presence of tumor hypoxia. In this overview we aim to evaluate the current evidence and potential clinical relevance of tumor hypoxia in head and neck cancer according to an extensive search of current literature.An abundance of evidence and often contradictory evidence is found in the literature. Even the contradictory evidence and comparisons are difficult to judge as criteria and methodologies differ greatly, furthermore few prospective observational studies exist for verification of the pre-clinical studies. Despite these discrepancies there is clear evidence of associations between prognosis and poor tumor oxygenation biomarkers such as HIF-1α, GLUT-1 and lactate, though these associations are not exclusive. The use of genetic markers is expanding and will probably lead to significantly more and complex evidence. The lack of oxygenation in head and neck tumors is of paramount importance for the prediction of treatment outcomes and prognosis. Despite the wide array of conflicting evidence, the drive towards non-invasive prediction of tumor hypoxia should continue.

Prevalence of human papillomavirus in oral squamous cell carcinomas in northern Spain

The aim of this study was to analyze the prevalence of high-risk HPV in oral squamous cell carcinoma (OSCC) in a northern Spanish population, as well as to ascertain the prognostic role of p16^INK4a expression. The examination samples were collected from paraffin tissue blocks, from 125 patients surgically treated between 1996 and 2007. All cases were histologically evaluated, and the presence of HPV was assessed by p16 and p53immunohistochemistry followed by DNA detection by in situ hybridization (ISH) and polymerase chain reaction (PCR) amplification using the combination of consensus primers MY11/GP6 + . Fourteen cases (11 %) were p16-immunopositive, and p53 was scored positive in 73 cases (58 %). Five cases (4 %) showed a simultaneous p16-positive and p53-negative immunostaining. ISH was negative in all the cases. Among the p16INK4a-immunopositive cases, PCR amplification failed to reveal HPV DNA in any tumor samples. There were no statistically significant differences in any clinical or pathological characteristics of the patients regarding p16^INK4a expression. T classification, neck-node metastasis, and clinical stage showed outcome relevance. However, no significant differences in cause-specific survival based on p16INK4a were observed. We did not find any high-risk HPV types in our patients, thus, are unlikely that HPV has an important role in the etiology of OSCC. p16INK4a protein was neither an accurate marker of HPV infection nor a prognosis marker in OSCC.

P53 codon 72 polymorphism, human papillomavirus infection, and their interaction to oral carcinoma susceptibility

Background

Tumor suppressor gene p53 plays an important role in the maintenance of the genomic integrity, and mutation in the gene may alter an individual’s susceptibility to various carcinomas. P53 Arg72Pro or codon 72 polymorphism has been indicated to increase the risk of developing certain cancers such as bladder cancer and cervical cancer. Human papillomavirus (HPV) infection has been shown as a risk factor for certain cancers such as cervical cancer and oral cancer as well, and the HPV oncoprotein E6 may induce the degradation of p53 function. However, the association between p53 Arg72Pro polymorphism and the risk of oral cancer with HPV infection remains inconclusive. Therefore, this meta-analysis involving 5,614 participants was performed to investigate the relations among the p53 Arg72Pro polymorphism, HPV infection, and the risk of developing oral cancer.

Results

A search of the literature by PubMed, Embase, Web of Science, and China National Knowledge Infrastructure databases was conducted to identify studies based on the inclusion and exclusion criteria. Odds ratios with 95 % confidence intervals were combined using a random-effect model or a fixed-effect model. The current study was conducted with 13 studies consisting of 2,413 cases and 3,201 controls. Neither overall analysis nor stratified analyses detected any obvious evidence of association between p53 Arg72Pro polymorphism and oral cancer susceptibility in all genetic models. However, a significant association between p53 Arg72Pro polymorphism and the risk of oral cancer with HPV infection was detected in the Arg/Arg vs. Arg/Pro + Pro/Pro model.

Conclusion

In the current meta-analysis which used the quantitative data synthesis for the first time, our study demonstrated that p53 Arg72Pro polymorphism together with HPV infection might jointly alter an individual’s susceptibility to the risk of oral cancer. Our results suggested that p53 Arg72Pro polymorphism may partly contribute to the pathogenesis of oral cancer development.

Human papillomavirus and cancerous diseases of the head and neck: a systematic review and meta-analysis

The increasing incidence of head and neck cancer (HNSCC) highlights the need to better understand the role of human papillomavirus (HPV) in the development of these cancers. The aims of this study were to conduct a systematic review and a meta-analysis concerning observational studies on the association between HPV infection and HNSCC and to quantify this association, thereby obtaining a reliable estimation of the risk of HPV infection in the development of head and neck cancer. Literature searches were performed using PubMed and Scopus databases. StatsDirect 2.7.8 program was used for the analysis. We found 15 case-control studies, 63 prevalence studies, and no cohort studies. The pooled odds ratio (OR) for all the included case-control studies resulted in a value of 1.63 (95% CI 1.27-2.09; P < 0.0001). The highest pooled OR resulted from the analysis of all the studies that examined HPV 16 genotype in association oral cavity (OR 5.36; 95% CI 1.4-20). The strong evidence of association between HPV infection and HNSCC highlights the importance of the introduction of specific tests in the cancer prevention practices to evaluate the presence of the virus, especially in the oral cavity, and the possibility of an extension of the vaccine anti-HPV in the male population too.

Human papillomavirus, smoking, and head and neck cancer

AIMS

Smoking and human papillomavirus (HPV) are both distinct risk factors for head and neck cancer, but the nature of interaction between these 2 risk factors in the development of head and neck cancer remains unclear. The purpose of this review is to determine the potential effect of smoking in causation of HPV-related head and neck carcinoma.

METHOD

A literature search was carried out using the keywords human papillomavirus, head and neck cancer, smoking, tobacco, and cervical cancer. The English-language articles, references, and other relevant studies evaluating the association of smoking, HPV, and risk of head and neck cancer were collected and analyzed.

CONCLUSION

Overall, our review points to smoking tobacco posing an additional risk for development of head and neck cancer in the presence of HPV infection. This is consistent with available laboratory data that show evidence of biological plausibility for interaction between smoking and progression of HPV infection to carcinogenesis. It is therefore important that cessation of smoking is promoted in smokers with HPV infection.

Incidence of human papillomavirus in oropharyngeal squamous cell carcinomas: now and 50 years ago

The increasing incidence of oropharyngeal squamous cell carcinomas is believed to be due to the growing proportion of human papillomavirus-positive oropharyngeal squamous cell carcinoma. To examine the time trend in the incidence of human papillomavirus, oropharyngeal squamous cell carcinomas diagnosed from 1956 to 1969 (n = 43) and from 2007 to 2009 (n = 54) were tested by p16 immunohistochemistry and in situ hybridization for human papillomavirus. Morphologically, in these 2 time periods, the predominant type of oropharyngeal squamous cell carcinoma changed from keratinizing to nonkeratinizing, with increase in nonkeratinizing cases from 28% to 67% (P < .001). Also, there was an increase in surgical resections versus biopsies (11% versus 46%; odds ratio, 6.6; P < .001) and base of tongue versus tonsillar location (20% versus 40%; odds ratio, 2.6; P = .04). The proportion of human papillomavirus-positive oropharyngeal squamous cell carcinoma increased from 35% to 72% (odds ratio, 4.9; P < .001). This increase was most apparent in men (odds ratio, 4.2; P < .001). This study provides the earliest historic baseline for human papillomavirus incidence in oropharyngeal squamous cell carcinoma and may serve as a reference point for evaluating the results of human papillomavirus infection preventive measures, such as human papillomavirus vaccination.

Human papillomavirus and oropharynx cancer: biology, detection and clinical implications

OBJECTIVES

To review evidence for the role of human papillomavirus (HPV) in the etiology of oropharyngeal cancers, methods of viral detection, and the resulting clinical implications.

STUDY DESIGN

Contemporary review.

METHODS

Published journal articles identified through PubMed and conference proceedings were reviewed.

RESULTS

HPV-associated squamous cell carcinomas represent a distinct disease entity from carcinogen-associated squamous cell carcinomas. HPV oncoproteins lead to mucosal cell transformation through well-defined mechanisms. Different methods of detecting HPV exist with variable levels of sensitivity and specificity for biologically active virus. Although virus is detected in a number of head and neck subsites, studies demonstrate improved outcomes in HPV-associated carcinoma of the oropharynx only. The cell cycle regulatory protein p16 is upregulated by biologically active HPV and serves as a biomarker of improved response to therapy.

CONCLUSIONS

HPV-associated squamous cell carcinoma of the oropharynx is a biologically distinct entity from carcinogen-associated carcinoma. Understanding the molecular mechanisms behind the improved outcomes in patients with HPV-associated oropharyngeal carcinoma may lead to novel therapeutics for patients with carcinogen-associated carcinomas.

Association of TGF-beta1 genetic variants with HPV16-positive oropharyngeal cancer

PURPOSE

Transforming growth factor-beta1 (TGF-beta1) plays an important role in inflammation and immune responses, which control the human papillomavirus (HPV) clearance and escape of immune surveillance, and may contribute to genetic susceptibility to HPV16 infection.

EXPERIMENTAL DESIGN

In this case series study, we analyzed the HPV16 status in tumor specimens and genotyped three TGF-beta1 polymorphisms using genomic DNA from the blood of 200 squamous cell carcinoma of the oropharynx (SCCOP) cases. We calculated odds ratio (OR) and 95% confidence intervals (95% CI) in univariate and multivariable logistic regression models to examine the association between the TGF-beta1 polymorphisms and HPV16 status in SCCOP.

RESULTS

Compared with those with the common homozygous genotype, the TGF-beta1 T869C variant genotypes were significantly associated with HPV16-positive tumor status among patients with SCCOP (OR, 1.97; 95% CI, 1.03-3.76), but no significant association was observed for the TGF-beta1 C509T or G915C polymorphism. When all variant genotypes were combined, however, SCCOP patients carrying genotypes with any of these TGF-beta1 variants were more than twice as likely to have an HPV16-positive tumor (OR, 2.28; 95% CI, 1.16-4.50) as patients with no variant genotypes. The stratified analysis showed that those under 54 years of age, non-Hispanic white patients, never smokers, and never drinkers with any variant TGF-beta1 genotypes were also more likely to have HPV16-positive tumors.

CONCLUSIONS

TGF-beta1 polymorphisms may serve as a susceptibility marker for tumor HPV16 status among SCCOP patients, particularly those who were never smokers and never drinkers. Large studies are needed to validate our findings.

Smoking modifies the relationship between XRCC1 haplotypes and HPV16-negative head and neck squamous cell carcinoma

Reports on the relationship between head and neck squamous cell carcinoma (HNSCC) and polymorphisms in X-ray cross complementing group 1 (XRCC1) have been inconsistent. We hypothesized this may be due to not accounting for Human papillomavirus type-16 (HPV16) and thus examined whether smoking modified the association between XRCC1 haplotypes and HNSCC risk within HPV16 serologic strata. Cases were diagnosed in Greater Boston, Massachusetts. Controls were matched to cases on age, gender and residential town. Genotyping was conducted on three XRCC1 polymorphisms (Arg194Trp, Arg280His and Arg399Gln) and serology was used to determine HPV16 exposure. Unconditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for age, sex, race, education, smoking, alcohol consumption and HPV16 serology. There was no overall association between XRCC1 polymorphisms and HNSCC risk. Smoking did not modify the association between XRCC1 polymorphisms and HNSCC risk among the HPV16 seropositive (p(interaction) = 0.89) but it did for the HPV16 seronegative (p(interaction)=0.04). Among the HPV16 seronegative, heavy smokers with a haplotype containing a variant allele had an increased HNSCC risk (haplotype with 399Gln: OR, 1.35; 95% CI, 0.97-1.86), whereas never/light smokers with variant alleles may have a reduced risk. In sum, the association between XRCC1 and HNSCC risk differed by HPV16 status and smoking. Among the HPV16 seronegative, heavy smokers with XRCC1 variant alleles had an increased HNSCC risk. There was no relationship between XRCC1 and HPV16-related HNSCC, regardless of smoking. Our findings underscore the importance of accounting for HPV16 exposure even when studying susceptibility to HNSCC.

Survival of squamous cell carcinoma of the head and neck in relation to human papillomavirus infection: review and meta-analysis

Human papillomavirus (HPV) has been associated with head and neck squamous cell carcinomas (HNSCC), especially of the oropharynx, with highest distribution in the tonsils. HPV infection has been associated with improved outcome, although not all the studies show consistent results. The reason for this is not clear. We reviewed all published articles and conducted a meta-analysis on the overall relationship between HPV infection and overall survival (OS) and disease-free survival (DFS) in HNSCC. Patients with HPV-positive HNSCC had a lower risk of dying (meta HR: 0.85, 95% CI: 0.7-1.0), and a lower risk of recurrence (meta HR: 0.62, 95%CI: 0.5-0.8) than HPV-negative HNSCC patients. Site-specific analyses show that patients with HPV-positive oropharyngeal tumours had a 28% reduced risk of death (meta HR: 0.72, 95%CI: 0.5-1.0) in comparison to patients with HPV-negative oropharyngeal tumours. Similar observations were made for DFS (meta HR: 0.51, 95% CI: 0.4-0.7). There was no difference in OS between HPV-positive and negative non-oropharyngeal patients. The observed improved OS and DFS for HPV-positive HNSCC patients is specific to the oropharynx; these tumours may have a distinct etiology from those tumours in non-oropharyngeal sites.

Role of human papillomavirus in the etiology of head and neck cancer

Head and neck cancer is the world's sixth most common cancer, but despite advances in treatment, there has been no significant decline in the mortality rate. In recent years, there has been mounting epidemiologic and experimental evidence of a role for human papillomavirus (HPV) as the etiologic agent of a subset of head and neck cancers. The association is strongest for oropharyngeal cancers, especially those of the tonsil. HPV 16 is invariably the predominant type. HPV-positive cancers have been shown to be biologically distinct, clustering among nonsmokers and light drinkers, and have been associated with a favorable prognosis. This review examines the current findings of HPV in head and neck cancers and discusses implications for developing new treatments.

Clinical implications of human papillomavirus in head and neck cancers

Human papillomavirus (HPV) is now recognized to play a role in the pathogenesis of a subset of head and neck squamous cell carcinomas (HNSCCs), particularly those that arise from the lingual and palatine tonsils within the oropharynx. High-risk HPV16 is identified in the overwhelming majority of HPV-positive tumors, which have molecular-genetic alterations indicative of viral oncogene function. Measures of HPV exposure, including sexual behaviors, seropositivity to HPV16, and oral, high-risk HPV infection, are associated with increased risk for oropharyngeal cancer. HPV infection may be altering the demographics of HNSCC patients, as these patients tend to be younger, nonsmokers, and nondrinkers. There is sufficient evidence to conclude that a diagnosis of HPV-positive HNSCC has significant prognostic implications; these patients have at least half the risk of death from HNSCC when compared with the HPV-negative patient. The HPV etiology of these tumors may have future clinical implications for the diagnosis, therapy, screening, and prevention of HNSCC.

Study of the viral infections and cytokines associated with recurrent aphthous ulceration

Mouth ulcers are one of the most common oral complaints. However, the association between oral ulceration and viruses and cytokines is uncertain. We detected the presence of human papilloma virus (HPV), cytomegalovirus (CMV), Epstein-Barr virus (EBV), herpes simplex virus (HSV)-1, HSV-2 and human herpesvirus (HHV)-8 DNA in oral tissues by polymerase chain reaction (PCR) and Southern hybridization techniques, and quantified the serum levels of cytokines including interleukin (IL)-2, IL-4, granulocyte-macrophage colony-stimulating factor (GM-CSF), soluble Fas (sFas) and the Fas ligand (FasL) by enzyme-linked immunosorbent assay (ELISA) for 67 recurrent aphthous ulcer (RAU) patients and 72 normal individuals. Seven patient specimens were excluded from the study due to the negative PCR results for the beta-globin used as the internal control. Among the 32 (53.3%) virus-positive results from 60 patients' samples, 8 (13.3%) HPV, 4 (6.7%) HSV-1, 11 (18.3%) CMV, 9 (15.0%) EBV, and 16 (26.7%) HHV-8 samples proved to be positive. No HSV-2-positive samples were found. The percentage of single-virus infection (56.3%) was significantly greater than that of double-virus co-infection (31.3%) and the percentage of double-virus co-infection was significantly greater than the percentage of triple-virus co-infection (12.5%) (P < 0.05). In the 72 normal oral-tissue specimens, no viral DNA was detected. The mean serum cytokine level for patients was significantly (P < 0.05) greater than for controls for most of the separate age groups. The mean serum cytokine concentrations for the patient group demonstrated a diffuse pattern covering a wide range of serum concentrations, a very different result from the compact serum concentration pattern and lower mean serum cytokine concentrations revealed by the normal group. Overall association between viruses and recurrent aphthous ulceration is HHV-8 > CMV > EBV > HPV > HSV-1, regarding the frequency of prevalence (P < 0.05).

Human papillomavirus-associated head and neck cancer is a distinct epidemiologic, clinical, and molecular entity

There is currently sufficient evidence to conclude that human papillomavirus (HPV) plays a role in the pathogenesis of a distinct subset of head and neck squamous cell cancers (HNSCC), particularly tonsillar cancers. There is a strong and consistent association between high-risk HPV types, specifically HPV16, a known human carcinogen, and these distinctive oropharyngeal cancers with molecular characteristics indicative of viral oncogene function. Risk for HPV-HNSCC is increased by certain sexual behaviors after consideration of alcohol and tobacco exposure, consistent with an extensive literature that has established HPV infection as a sexually transmitted disease. Furthermore, exposure to HPV16 has been associated with increased risk for subsequent development of oropharyngeal cancer. Prophylactic and therapeutic vaccines targeted against the viral capsid components and oncoproteins will provide the ultimate evidence for a role for HPV in HNSCC, if demonstrated to be effective in the prevention or therapy of this disease. It is time for clinician scientists to translate knowledge of this newly recognized disease entity into potential applications for the prevention, detection, and treatment of HPV-HNSCC.

Head and neck cancer: The pursuit of molecular diagnostic markers

From a histopathologic perspective, head and neck squamous cell carcinoma (HNSCC) is a relatively straightforward diagnosis. However, the clinically useful information presently provided by pathologists is embarrassingly limited. Similarly, our ability to accurately identify the earliest premalignant lesions as well as predict which premalignant lesions are likely to progress to HNSCC is limited. Over the last decade, an explosive growth of knowledge related to the molecular biology of this disease has occurred, which is now being used to address these issues. For example, we now appreciate that there are multiple etiologies and multiple molecular mechanisms responsible for the development of HNSCC. New techniques have improved our ability to identify molecularly premalignant, but histologically benign lesions. Similarly, recent studies have been able to predict which premalignant lesions are likely to progress to HNSCC. In addition to having utility in the realm of early diagnosis, molecular diagnostics may have a profound impact on how we diagnose and report HNSCC. While still in the developmental stage, molecular protocols are being used to evaluate surgical margins, determine the location of unknown primary tumors, identify histologically undetectable lymph node metastasis, and predict which tumors are more likely to respond to a particular postsurgical adjuvant therapy.

Comparative study of HPV prevalence in Japanese and North-east Chinese oral carcinoma

BACKGROUND

Human papillomavirus (HPV) plays a role in the development of oral carcinoma. However, the reported prevalence of HPV in oral carcinoma has varied widely.

METHODS

The prevalence of HPV 16, 18 and 33 was investigated in Japanese and North-east Chinese oral squamous cell carcinomas (OSCCs) with polymerase chain reaction (PCR). The expression of p53 protein was examined immunohistochemically.

RESULTS

HPV 16 and 18 were detected in 7 (23.3%) and 10 (33.3%) of 30 Japanese and 11 (36.7%) and 5 (16.7%) of 30 Chinese samples, respectively. HPV 16 and 18 coinfection was detected in 3/30 Japanese and 2/30 Chinese samples. HPV 33 was not detected. There was no significant correlation between HPV 16 and 18 and the sites, gender, age and histological grade. The prevalence of both HPV 16 and 18 was similar and higher in the Japanese and North-east Chinese samples (46.7% each). HPV 16 or/and 18 infection or/and p53 overexpression were in 22 (73.3%) of 30 Japanese samples and 24 (80.0%) of 30 North-east Chinese samples, respectively.

CONCLUSIONS

HPV 16/18 infection or/and p53 overexpression may play an important role in developing some OSCCs. and the presence of HPV sequences and mutant p53 are not necessarily mutually exclusive.

Molecular genetics of head and neck cancer

BACKGROUND

Head and neck cancers have multiple genetic abnormalities that influence tumor behavior and may be useful in developing new treatments.

METHODS

Genetic alterations implicated in head and neck cancer oncogenesis and behavior are reviewed, and molecular techniques for detection and treatment are evaluated.

RESULTS

The large number of genetic changes present in head and neck cancer cells precludes meaningful use of simple molecular tests and treatments. Detection of abnormalities in multiple genes provides better prognostic information than the detection and assessment of single mutations. Screening tests that rely on amplification of genetic material present in bodily fluids are hindered by the genomic complexity of head and neck cancer. Introduction of genetic material into head and neck cancer cells for gene therapy has shown some efficacy.

CONCLUSIONS

Head and neck cancers comprise a complex genetic disease. Although much has been learned about the molecular genetics of head and neck cancers, continued study of multiple genes is critical for further progress. Gene therapy, although promising, must also overcome this complexity.

P53 and Ki-67 as outcome predictors for advanced squamous cell cancers of the head and neck treated with chemoradiotherapy

HYPOTHESIS

P53 and Ki-67 status will predict response to treatment, organ preservation, and survival in patients with advanced squamous cell cancers of the head and neck treated with chemoradiotherapy (CRT).

STUDY DESIGN

Retrospective analysis of p53 and Ki-67 status from the CRT arm of a randomized, controlled trial (n = 50) and from patients receiving the same treatment but not enrolled in the trial (n = 55).

METHODS

P53 and Ki-67 status were established from archived tissue samples using immunohistochemical (IHC) staining. Tumors were positive for p53 (p53+) when more than 2% of cells stained for p53 and were positive for Ki-67 (Ki-67+) when any cell stained for Ki-67. End points were tumor response, tumor recurrence, survival status, and organ preservation at last follow-up, and time to events. Predictive models were calculated for each outcome.

RESULTS

Neither marker predicted tumor response to treatment. P53+ status was associated with tumor recurrence (P =.003) and locoregional recurrence (P =.003). Adjusting for time to event, p53+ status was significantly related to a lower recurrence-free survival (P =.004), lower disease-specific survival (P =.04), lower overall survival with primary site preservation (P =.03), and lower disease-specific survival with primary site preservation (P =.003). Multivariate analysis revealed that p53+ status was significantly related to a lower recurrence-free survival (P =.01, risk ratio [RR] = 3.65) and lower disease-specific survival with organ preservation (P =.02, RR = 3.41). Ki-67+ status was not related to any variables. However, multivariate analysis revealed that Ki-67+ was significantly related to a lower overall survival (P =.05, RR = 2.03). The combination of both markers negative (p53-/Ki-67-) was associated with a lower incidence of tumor recurrence (P =.02), lower locoregional recurrence (P =.01), and fewer second primary lesions (P =.04). Adjusting for time to event, p53-/Ki-67- status was significantly related to a higher recurrence-free survival (P =.02), higher disease-specific survival with primary site preservation (P =.02), and higher overall survival with primary site preservation (P =.02). Multivariate analysis revealed that p53-/Ki-67- status was significantly related to a higher overall survival with site preservation (P =.01, RR = 2.78).

CONCLUSIONS

P53 and Ki-67 status appear to be related to the various survival end points considered in this study. However, this relation does not seem to be sufficient to warrant treatment modifications. Closer follow-up may be justified in both p53+ and Ki67+ patients to detect recurrence or a second primary at an earlier stage, possibly improving survival.

Human papillomavirus positive squamous cell carcinoma of the oropharynx: a radiosensitive subgroup of head and neck carcinoma

BACKGROUND

Epidemiologic evidence points to a connection between viral infection by the human papillomavirus (HPV) and a subgroup of squamous cell carcinoma of the oropharynx. To assess the impact of HPV infection on the response of these tumors toward radiotherapy, the authors retrospectively determined the presence of the virus and the integrity of the viral E2 gene in tumors of patients who have undergone curative irradiation.

METHODS

Paraffin embedded biopsies from 99 patients were analyzed for HPV infection and E2 gene integrity by multiplex PCR. The experimental findings were correlated with clinical characteristics, known risk factors, and treatment outcome.

RESULTS

Fourteen of 99 tumors were HPV positive (11 HPV16, 1 HPV33, 1 HPV35, and 1 HPV45). Human papillomavirus positivity was closely linked to female gender (odds ratio [OR], 5.75; P = 0.004), age older than 56 years (OR, 7.42; P = 0.012), nonsmokers (OR, 21.33; P = 0.00001), and alcohol abstainers (OR, 5.35; P = 0.012). There was an inverse association with p53 nuclear immunoreactivity (OR, 0.06; P = 0.008). The Kaplan-Meier survival estimates showed a better local control (P = 0.050, log-rank) and a better overall survival (P = 0.046, log-rank) for patients with HPV positive tumors. In the multivariate analysis, HPV positivity remained to be associated with a lower risk of local failure (risk ratio [RR], 0.31; P = 0.048). Four of 11 HPV16 positive tumors had a disrupted E2 gene. Only tumors with a disrupted E2 gene manifested local treatment failure.

CONCLUSIONS

Human papillomavirus positivity designates a specific subgroup of oropharyngeal squamous cell carcinomas of the oropharynx that arise preferentially among individuals with no consumption of tobacco and alcohol and that have a favorable outcome attributable to an increased sensitivity toward radiotherapy.

Detection of HPV in Japanese and Chinese oral carcinomas by in situ PCR

Human papillomavirus (HPV) is established as the cause of almost 100% of cervical carcinomas. However, the association of HPV with oral squamous cell carcinomas (SCCs) is less well understood. We examined the prevalence of HPV in oral SCCs in samples of Japanese and Chinese populations. Using in situ polymerase chain reaction (PCR) analysis (MY09 and MY11 consensus primers), HPV was detected in the nucleus of epithelia and tumor cells in oral lesions. Analysis revealed the specific presence of HPV DNA in all cases of SCC in our Japanese (10/10) and Chinese (10/10) population samples. These results suggest that HPV infection could be one of several risk factors contributing to oral SCC in Japanese and Chinese.

Papillary squamous cell carcinomas of the upper aerodigestive tract: a clinicopathologic and molecular study

BACKGROUND

The limited studies and the small number of published cases of papillary squamous cell carcinoma have precluded accurate assessment of the biologic characteristics of this lesion.

METHODS

Thirty-eight of the carcinomas were studied. In-situ hybridization and polymerase chain reaction were performed to detect human papilloma virus (HPV) and p53 expression.

RESULTS

HPV was found in 4 of 14 assessable carcinomas by in-situ hybridization and in 5 of 14 by polymerase chain reaction. The most frequently identified HPVs were HPVs in 6/11 and 16/18 patients. In general, a reciprocal relationship was found between p53 and HPV prevalence. The most lethal site for this tumor was the sinonasal tract, whereas patients with papillary squamous cell carcinomas of the larynx had the best outlook. Eleven of 25 (44%) assessable patients died of disease (mean time interval, 2 year).

CONCLUSIONS

Papillary squamous cell carcinoma of the upper aerodigestive tract is a distinct variant of squamous cell carcinoma. As such and because of its putative association with HPV, papillary squamous cell carcinoma could be an informative model for defining how viral oncogenes cooperate with other factors in genomic instability, carcinogenesis, and tumor development.

"High risk" HPV types are frequently detected in potentially malignant and malignant oral lesions, but not in normal oral mucosa

Studies on the involvement of the human papillomavirus (HPV) in initiation and progression of oral neoplasia have generated conflicting results. The observed discrepancy is attributable mainly to the varying sensitivity of the applied methodologies and to epidemiologic factors of the examined patient groups. To evaluate the role of HPV in oral carcinogenesis, we analyzed 53 potentially neoplastic and neoplastic oral lesions consisting of 29 cases of hyperplasia, 5 cases of dysplasia, and 19 cases of squamous cell carcinomas, as well as 16 oral specimens derived from healthy individuals. A highly sensitive nested polymerase chain reaction (PCR) assay was used, along with type-specific PCR, restriction fragment length polymorphism analysis, dot blotting, and nonisotopic in situ hybridization. Nested PCR revealed the presence of HPV DNA in 48 of the 53 (91%) pathologic samples analyzed, whereas none (0%) of the normal specimens was found to be infected. Positivity for HPV was independent of histology and the smoking habits of the analyzed group of patients. At least one "high risk" type, such as HPV 16, 18, and 33, was detected by type-specific PCR in 47 (98%) infected specimens, whereas only 1 (2%) squamous cell carcinoma was solely infected by a "low risk" type (HPV 6). HPV 16 was the prevailing viral type, being present in 71% of infected cases. Single HPV 16 and HPV 18 infections were confirmed by restriction fragment length polymorphism. HPV 58 was detected by dot blotting in three hyperplastic lesions. HPV positivity and genotyping were further confirmed, and the physical status of this virus was evaluated by nonisotopic in situ hybridization. Diffuse and punctate signals, indicative of the episomal and integrative pattern of HPV infection, were observed for low- and high-risk types, respectively. Our findings are suggestive of an early involvement of high-risk HPV types in oral carcinogenesis.

p53 gene status as a predictor of tumor response to induction chemotherapy of patients with locoregionally advanced squamous cell carcinomas of the head and neck

PURPOSE

To determine whether p53 gene status predicts tumor responses to platinum- and fluorouracil-based induction chemotherapy in locoregionally advanced squamous cell carcinomas of the head and neck.

PATIENTS AND METHODS

Tumor responses of 105 patients were measured at the primary tumor site. Objective response and major response were defined by a 50% and 80% reduction in tumor size, respectively. All coding parts of p53 gene were directly sequenced. p53 expression in tumor cells was determined by immunohistochemistry. Human papillomavirus infection was detected by polymerase chain reaction. Odd ratios were adjusted by stepwise logistic regression analysis.

RESULTS

p53 mutations, p53 expression, and tumor stage were sufficient to explain the variation in tumor responses to chemotherapy in multivariate models. p53 mutation was the only variable to significantly predict objective response (odds ratio, 0. 23; 95% confidence interval, 0.10 to 0.57; P =.002) and was the strongest predictor of major response (odds ratio, 0.29; 95% confidence interval, 0.11 to 0.74; P =.006). p53 expression (odds ratio, 0.39; 95% confidence interval, 0.16 to 0.98) and tumor stage (odds ratio, 0.31; 95% confidence interval, 0.10 to 0.96) also predicted major response. Specific mutations (contact mutations) accounted for much of the reduction in the risk of major response associated with overall mutations. In complementary analyses, p53 expression was weakly predictive of major response in the subgroup with wild-type p53, and p53 mutations also predicted histologic response.

CONCLUSION

p53 gene mutations are strongly associated with a poor risk of both objective and major responses to chemotherapy. Contact mutations are associated with the lowest risk of major response to chemotherapy.