Cancer of the oropharynx

Targeted Therapy with PI3K, PARP, and WEE1 Inhibitors and Radiotherapy in HPV Positive and Negative Tonsillar Squamous Cell Carcinoma Cell Lines Reveals Synergy while Effects with APR-246 Are Limited

Human papillomavirus positive (HPV⁺) tonsillar and base of tongue cancer (TSCC/BOTSCC) is rising in incidence, but chemoradiotherapy is not curative for all. Therefore, targeted therapy with PI3K (BYL719), PARP (BMN-673), and WEE1 (MK-1775) inhibitors alone or combined was pursued with or without 10 Gy and their effects were analyzed by viability, proliferation, and cytotoxicity assays on the TSCC/BOTSCC cell lines HPV⁺ UPCI-SCC-154 and HPV^- UT-SCC-60A. Effective single drug/10 Gy combinations were validated on additional TSCC lines. Finally, APR-246 was assessed on several TSCC/BOTSCC cell lines. BYL719, BMN-673, and MK-1775 treatments induced dose dependent responses in HPV⁺ UPCI-SCC-154 and HPV^- UT-SCC-60A and when combined with 10 Gy, synergistic effects were disclosed, as was also the case upon validation. Using BYL719/BMN-673, BYL719/MK-1775, or BMN-673/MK-1775 combinations on HPV⁺ UPCI-SCC-154 and HPV^- UT-SCC-60A also induced synergy compared to single drug administrations, but adding 10 Gy to these synergistic drug combinations had no further major effects. Low APR-246 concentrations had limited usefulness. To conclude, synergistic effects were disclosed when complementing single BYL719 BMN-673 and MK-1775 administrations with 10 Gy or when combining the inhibitors, while adding 10 Gy to the latter did not further enhance their already additive/synergistic effects. APR-246 was suboptimal in the present context.

Prognostic factors in oropharyngeal squamous cell carcinoma in the state of São Paulo, Brazil: 10-year follow-up

OBJECTIVE

To descriptively analyze the epidemiological data, clinical stage, and outcomes of oropharyngeal squamous cell carcinoma in the state of São Paulo, Brazil, and to estimate the influence of clinical stage and treatment type on overall and disease-free survival.

METHODS

We retrospectively analyzed epidemiological data from the São Paulo Cancer Center Foundation database relative to patients with oropharyngeal squamous cell carcinoma diagnosed between 2004 and 2014 in the state of São Paulo. Univariate and multivariate Cox regression analyses were performed to assess factors associated with the outcomes. A forward stepwise selection procedure was used. Survival curves were estimated by the Kaplan-Meier method and compared by the Gehan-Breslow-Wilcoxon test.

RESULTS

A total of 8075 individuals with oropharyngeal squamous cell carcinoma were identified. Of these, 86.3% were diagnosed at an advanced stage and 13.7% at an early stage. Only 27.2% of patients were treated surgically, whereas 57.5% were treated medically. Patients undergoing surgery had longer overall survival than those receiving medical treatment in both early- and advanced-stage oropharyngeal squamous cell carcinoma. However, there was no significant difference in disease-free survival between surgical and medical treatment.

CONCLUSION

No significant difference in disease-free survival between medical and surgical treatment suggests similar complete remission rates with both approaches. Patients receiving medical treatment had shorter overall survival, which may be due to complications from chemotherapy and radiotherapy. However, we cannot confirm this relationship based on the data provided by the São Paulo Cancer Center Foundation. Prospective studies are warranted to assess whether the lower overall survival rate in patients receiving medical treatment is secondary to complications from chemotherapy and radiotherapy.

LEVEL OF EVIDENCE

2C.

Effect of Cryotherapy plus Flurbiprofen Axetil for Pain Management in Children Undergoing Tonsillectomy

Objective

To investigate the effect of cryotherapy using ice pops for physical analgesia and preventive analgesia using flurbiprofen axetil for pain management in children undergoing tonsillectomy.

Methods

A total of 120 children scheduled for tonsillectomy were recruited after assessment for eligibility and assigned to a control group (group C), flurbiprofen axetil group (group F), cryotherapy group (group I), and cryotherapy plus flurbiprofen axetil group (Group FI) via the random number table method. Groups F and FI were given 1 mg/kg of flurbiprofen axetil through intravenous injection 30 min before surgery, while group C received an equal amount of saline at the same time point. Groups I and FI received sweet ice pops for pain relief after recovery from anesthesia. The modified Children's Hospital of Eastern Ontario Pain Scale (mCHEOPS) scores and pediatric anesthesia emergence delirium (PAED) scores at 5 minutes (T1), 30 minutes (T2), 60 minutes (T3), 4 hours (T4), and 24 hours (T5) postoperatively, and the incidence of postoperative complications in the children were recorded by investigators who were masked to the grouping results.

Results

From T1 to T4, significantly lower mCHEOPS scores and PAED scores were observed in group F, group I, and group FI versus those in group C (P < 0.05). At T2, group FI showed significantly lower mCHEOPS scores and PAED scores versus groups F and I (P < 0.05). There were no significant differences in the mCHEOPS scores and PAED scores between the four groups at 24 h postoperatively (P > 0.05). The differences in the documented postoperative complications between the four groups did not come up to the statistical standard (P > 0.05).

Conclusion

Cryotherapy plus flurbiprofen axetil for pain management significantly mitigates post-tonsillectomy pain and delirium in children and facilitates recovery, with no significant adverse events.

Targeted Therapy of HPV Positive and Negative Tonsillar Squamous Cell Carcinoma Cell Lines Reveals Synergy between CDK4/6, PI3K and Sometimes FGFR Inhibitors, but Rarely between PARP and WEE1 Inhibitors

Human papillomavirus positive (HPV+) tonsillar and base of tongue squamous cell carcinoma (TSCC/BOTSCC) have a favorable outcome, but upon relapse, survival is poor and new therapeutical options are needed. Recently, we found synergistic effects by combining the food and drug administration approved (FDA) phosphoinositide 3-kinase (PI3K) and fibroblast-growth-factor-receptor (FGFR) inhibitors BYL719 and JNJ-42756493 on TSCC cell lines. Here this approach was extended and Cyclin-Dependent-Kinase-4/6 (CDK4/6) and Poly-ADP-ribose-polymerase (PARP) and WEE1 inhibitors PD-0332991, and MK-1775 respectively were also examined. HPV+ CU-OP-2, -3, -20, and HPV- CU-OP-17 TSCC cell lines were treated with either BYL719 and JNJ-42756493, PD-0332991 BMN-673 and MK-1775 alone or in different combinations. Viability, proliferation, and cytotoxicity were followed by WST-1 assays and the IncuCyte S3 Live® Cell Analysis System. All inhibitors presented dose-dependent inhibitory effects on tested TSCC lines. Synergy was frequently obtained when combining CDK4/6 with PI3K inhibitors, but only sometimes or rarely when combining CDK4/6 with FGFR inhibitors or PARP with WEE1 inhibitors. To conclude, using CDK4/6 with PI3K or FGFR inhibitors, especially PD-0332991 with BYL719 presented synergy and enhanced the decrease of viability considerably, while although dose dependent responses were obtained with PARP and WEE1 inhibitors (BMN-673 and MK-1775 resp.), synergy was rarely disclosed.

A case report of interdigitating dendritic cell sarcoma originating from the oropharynx

Interdigitating dendritic cell sarcoma is an extremely rare tumor and typically originates from lymph nodes. Here, we report a patient with tumor originated from the oropharynx who received successful surgical treatment.

Prognostic Markers and Driver Genes and Options for Targeted Therapy in Human-Papillomavirus-Positive Tonsillar and Base-of-Tongue Squamous Cell Carcinoma

The incidence of Human-papillomavirus-positive (HPV⁺) tonsillar and base-of-tongue squamous cell carcinoma (TSCC and BOTSCC, respectively) is increasing epidemically, but they have better prognosis than equivalent HPV-negative (HPV⁻) cancers, with roughly 80% vs. 50% 3-year disease-free survival, respectively. The majority of HPV⁺ TSCC and BOTSCC patients therefore most likely do not require the intensified chemoradiotherapy given today to head and neck cancer patients and would with de-escalated therapy avoid several severe side effects. Moreover, for those with poor prognosis, survival has not improved, so better-tailored alternatives are urgently needed. In line with refined personalized medicine, recent studies have focused on identifying predictive markers and driver cancer genes useful for better stratifying patient treatment as well as for targeted therapy. This review presents some of these endeavors and briefly describes some recent experimental progress and some clinical trials with targeted therapy.

Incidence of pain complaints in oropharyngeal squamous cell carcinoma

OBJECTIVE

The purpose of this study was to determine the prevalence of throat pain and otalgia as presenting symptoms in patients with oropharyngeal squamous cell carcinoma (OPSCC) stratified by the cancer being their first or recurrent/second primary head and neck cancer (fHNC or rsHNC).

STUDY DESIGN

A retrospective analysis of patients operated on for OPSCC was performed. The primary predictor variable was HNC instance (fHNC/rsHNC) with outcome variables of throat pain and/or otalgia. Chi-square analysis was performed to test for significant associations between HNC instance and pain variables. Unadjusted odds ratios were calculated.

RESULTS

Eighty-nine patients met the inclusion criteria. Patients with OPSCC as an rsHNC had 4.67 times higher odds of throat pain (95% confidence interval [CI], 1.45-15.06) than those with OPSCC as an fHNC and had 20.22 times higher odds of simultaneous throat pain and otalgia (95% CI, 4.76-85.97) than those presenting with an fHNC. Current smoking status and human papillomavirus (HPV)-negative disease were also significantly predictive of rsHNC. HPV-negative disease was also predictive of pain.

CONCLUSIONS

In addition to the known associations of smoking and HPV status on recurrence and pain, there is a statistically significant association between cancer instance and pain in patients presenting with newly diagnosed, operable OPSCC.

The Appearance of 4-Hydroxy-2-Nonenal (HNE) in Squamous Cell Carcinoma of the Oropharynx

Tumor growth is associated with oxidative stress, which causes lipid peroxidation. The most intensively studied product of lipid peroxidation is 4-hydroxy-2-nonenal (HNE), which is considered as a “second messenger of free radicals” that binds to proteins and acts as a growth-regulating signaling factor. The incidence of squamous cell carcinoma of the oropharynx is associated with smoking, alcohol and infection of human papilloma virus (HPV), with increasing incidence world-wide. The aim of this retrospective study involving 102 patients was to determine the immunohistochemical appearance of HNE-protein adducts as a potential biomarker of lipid peroxidation in squamous cell carcinoma of the oropharynx. The HNE-protein adducts were detected in almost all tumor samples and in the surrounding non-tumorous tissue, while we found that HNE is differentially distributed in squamous cell carcinomas in dependence of clinical stage and histological grading of these tumors. Namely, the level of HNE-immunopositivity was increased in comparison to the normal oropharyngeal epithelium in well- and in moderately-differentiated squamous cell carcinoma, while it was decreasing in poorly differentiated carcinomas and in advanced stages of cancer. However, more malignant and advanced cancer was associated with the increase of HNE in surrounding, normal tissue. This study confirmed the onset of lipid peroxidation, generating HNE-protein adducts that can be used as a valuable bioactive marker of carcinogenesis in squamous cell carcinoma of the oropharynx, as well as indicating involvement of HNE in pathophysiological changes of the non-malignant tissue in the vicinity of cancer.

A global epidemic increase of an HPV-induced tonsil and tongue base cancer - potential benefit from a pan-gender use of HPV vaccine

In 2007, human papillomavirus (HPV) type 16 was finally recognized as a risk factor, besides smoking and alcohol, for oropharyngeal squamous cell carcinoma (OPSCC), including tonsillar squamous cell carcinoma (TSCC), by the International Agency for Research against Cancer. Just before, in 2006, the Food and Drug Administration had approved Gardasil, the first vaccine against HPV16, 18, 6 and 11, for preventive vaccination women against cervical cancer. Concurrently, some Western countries, where smoking was decreasing, disclosed an epidemic increase in the incidence of OPSCC, especially of TSCC and base of tongue cancer (BOTSCC), together accounting for 80-90% of all OPSCCs, and mainly affecting men. The epidemic was later revealed to be due to a rise in HPV-positive cases, and scientists in the field suggested HPV vaccination also of boys. Globally, there are roughly 96 000 incident OPSCC cases/year of which 20-24% are caused by HPV, thereby accounting for around 22 000 OPSCC cases annually. Of these cases, 80-90% are due to HPV16 infection and would be prevented with the presently registered HPV vaccines. In Western countries, such as Sweden (with almost 400 TSCC and BOTSCC cases per year) and the United States, HPV prevalence in OPSCC is higher and around 70%. HPV vaccination of girls has been initiated in many countries, and the vaccines have been efficient and their side effects limited. HPV vaccination of boys has, however, been the exception, but should definitely not be delayed any further. It would benefit both girls and boys directly, and result in better and more robust herd immunity. Today, we have the possibility to eliminate several high-risk HPV types in the younger generations and avoid more than 600 000 cancer cases annually worldwide, and this possibility should be embraced by offering global pan-gender HPV vaccination.

Inhibition of Epstein-Barr Virus Replication in Human Papillomavirus-Immortalized Keratinocytes

Epstein-Barr virus (EBV) is implicated in the pathogenesis of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OSCC). EBV-associated cancers harbor a latent EBV infection characterized by a lack of viral replication and the expression of viral oncogenes. Cellular changes promoted by HPV are comparable to those shown to facilitate EBV latency, though whether HPV-positive cells support a latent EBV infection has not been demonstrated. Using a model of direct EBV infection into HPV16-immortalized tonsillar cells grown in organotypic raft culture, we showed robust EBV replication in HPV-negative rafts but little to no replication in HPV-immortalized rafts. The reduced EBV replication was independent of immortalization, as human telomerase-immortalized normal oral keratinocytes supported robust EBV replication. Furthermore, we observed reduced EBV lytic gene expression and increased expression of EBER1, a noncoding RNA highly expressed in latently infected cells, in the presence of HPV. The use of human foreskin keratinocyte rafts expressing the HPV16 E6 and/or E7 oncogene(s) (HPV E6 and E7 rafts) showed that E7 was sufficient to reduce EBV replication. EBV replication is dependent upon epithelial differentiation and the differentiation-dependent expression of the transcription factors KLF4 and PRDM1. While KLF4 and PRDM1 levels were unaltered, the expression levels of KLF4 transcriptional targets, including late differentiation markers, were reduced in HPV E6 and E7 rafts compared to their levels in parental rafts. However, the HPV E7-mediated block in EBV replication correlated with delayed expression of early differentiation markers. Overall, this study reveals an HPV16-mediated block in EBV replication, through E7, that may facilitate EBV latency and long-term persistence in the tumor context.IMPORTANCE Using a model examining the establishment of EBV infection in HPV-immortalized tissues, we showed an HPV-induced interruption of the normal EBV life cycle reminiscent of a latent EBV infection. Our data support the notion that a persistent EBV epithelial infection depends upon preexisting cellular alterations and suggest the ability of HPV to promote such changes. More importantly, these findings introduce a model for how EBV coinfection may influence HPV-positive (HPV-pos) OSCC pathogenesis. Latently EBV-infected epithelial cells, as well as other EBV-associated head-and-neck carcinomas, exhibit oncogenic phenotypes commonly seen in HPV-pos OSCC. Therefore, an HPV-induced shift in the EBV life cycle toward latency would not only facilitate EBV persistence but also provide additional viral oncogene expression, which can contribute to the rapid progression of HPV-pos OSCC. These findings provide a step toward defining a role for EBV as a cofactor in HPV-positive oropharyngeal tumors.

Epstein-Barr virus in the pathogenesis of oral cancers

Epstein-Barr virus (EBV) is a ubiquitous gamma-herpesvirus that establishes a lifelong persistent infection in the oral cavity and is intermittently shed in the saliva. EBV exhibits a biphasic life cycle, supported by its dual tropism for B lymphocytes and epithelial cells, which allows the virus to be transmitted within oral lymphoid tissues. While infection is often benign, EBV is associated with a number of lymphomas and carcinomas that arise in the oral cavity and at other anatomical sites. Incomplete association of EBV in cancer has questioned if EBV is merely a passenger or a driver of the tumorigenic process. However, the ability of EBV to immortalize B cells and its prevalence in a subset of cancers has implicated EBV as a carcinogenic cofactor in cellular contexts where the viral life cycle is altered. In many cases, EBV likely acts as an agent of tumor progression rather than tumor initiation, conferring malignant phenotypes observed in EBV-positive cancers. Given that the oral cavity serves as the main site of EBV residence and transmission, here we review the prevalence of EBV in oral malignancies and the mechanisms by which EBV acts as an agent of tumor progression.

Trismus following different treatment modalities for head and neck cancer: a systematic review of subjective measures

The aim of this review was to compare systematically the subjective measure of trismus between different interventions to treat head and neck cancer, particularly those of the oropharynx. Using The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) Guidelines, Six databases were searched for the text using various terms which include “oropharyngeal/head and neck cancer”, “trismus/mouth opening” and the various treatment modalities. Included in the review were clinical studies (> or =10 patients). Three observers independently assessed the papers identified. Among the six studies reviewed, five showed a significantly worst outcome with regard to the quality-of-life questionnaire scores for a radiotherapy or surgery and radiotherapy (RT) ± chemotherapy or chemoradiotherapy when compared to surgery alone. Only one study showed no significant difference between surgery alone and other treatment modalities. Subjective quality-of-life measures are a concurrent part of modern surgical practice. Although subjective measures were utilised to measure post operative trismus successfully, there was no consensus as to which treatment modality had overall better outcomes, with conflicting studies in keeping with the current debate in this field. Larger and higher quality studies are needed to compare all three treatment modalities.

Human papillomavirus DNA detection in fine-needle aspirates as indicator of human papillomavirus-positive oropharyngeal squamous cell carcinoma: A prospective study

BACKGROUND

Human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (SCC) has a better outcome than most head neck squamous cell carcinomas (HNSCCs) and an HPV-positive lymph node metastasis likely has an HPV-positive oropharyngeal SCC origin. Determining HPV-status in cervical lymph nodes by fine-needle aspiration cytology (FNAC) may be useful for diagnosis.

METHODS

FNACs from 66 patients with neck masses were prospectively examined for HPV DNA and HPV16 mRNA by a polymerase chain reaction (PCR)-based assay, and the data correlated to diagnosis and HPV-status obtained from histopathological specimens.

RESULTS

Aspirates from 17 of 66 patients, later diagnosed with HPV-positive oropharyngeal SCC, were HPV16 DNA-positive. HPV16 mRNA was detected in all cases with extractable RNA. All remaining FNACs, including 18 branchial cleft cysts, were HPV DNA-negative. HPV DNA status in the aspirates showed perfect concordance with corresponding biopsies.

CONCLUSION

HPV16 DNA detection in fine-needle aspirations from neck masses is reliable and HPV16 DNA in a metastasis is a strong indicator of an HPV-positive oropharyngeal SCC. © 2016 Wiley Periodicals, Inc. Head Neck 39: 419-426, 2017.

The interaction between human papillomavirus and other viruses

The etiological role of human papillomavirus (HPV) in anogenital tract and head and neck cancers is well established. However, only a low percentage of HPV-positive women develop cancer, indicating that HPV is necessary but not sufficient in carcinogenesis. Several biological and environmental cofactors have been implicated in the development of HPV-associated carcinoma that include immune status, hormonal changes, parity, dietary habits, tobacco usage, and co-infection with other sexually transmissible agents. Such cofactors likely contribute to HPV persistent infection through diverse mechanisms related to immune control, efficiency of HPV infection, and influences on tumor initiation and progression. Conversely, HPV co-infection with other factors may also harbor anti-tumor effects. Here, we review epidemiological and experimental studies investigating human immunodeficiency virus (HIV), herpes simplex virus (HSV) 1 and 2, human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), BK virus (BKV), JC virus (JCV), and adeno-associated virus (AAV) as viral cofactors in or therapeutic factors against the development of genital and oral HPV-associated carcinomas.

Common fragile sites (CFS) and extremely large CFS genes are targets for human papillomavirus integrations and chromosome rearrangements in oropharyngeal squamous cell carcinoma

Common fragile sites (CFS) are chromosome regions that are prone to form gaps or breaks in response to DNA replication stress. They are often found as hotspots for sister chromatid exchanges, deletions, and amplifications in different cancers. Many of the CFS regions are found to span genes whose genomic sequence is greater than 1 Mb, some of which have been demonstrated to function as important tumor suppressors. CFS regions are also hotspots for human papillomavirus (HPV) integrations in cervical cancer. We used mate-pair sequencing to examine HPV integration events and chromosomal structural variations in 34 oropharyngeal squamous cell carcinoma (OPSCC). We used endpoint PCR and Sanger sequencing to validate each HPV integration event and found HPV integrations preferentially occurred within CFS regions similar to what is observed in cervical cancer. We also found that many of the chromosomal alterations detected also occurred at or near the cytogenetic location of CFSs. Several large genes were also found to be recurrent targets of rearrangements, independent of HPV integrations, including CSMD1 (2.1Mb), LRP1B (1.9Mb), and LARGE1 (0.7Mb). Sanger sequencing revealed that the nucleotide sequences near to identified junction sites contained repetitive and AT-rich sequences that were shown to have the potential to form stem-loop DNA secondary structures that might stall DNA replication fork progression during replication stress. This could then cause increased instability in these regions which could lead to cancer development in human cells. Our findings suggest that CFSs and some specific large genes appear to play important roles in OPSCC. © 2016 Wiley Periodicals, Inc.

Mate-Pair Sequencing as a Powerful Clinical Tool for the Characterization of Cancers with a DNA Viral Etiology

DNA viruses are known to be associated with a variety of different cancers. Human papillomaviruses (HPV) are a family of viruses and several of its sub-types are classified as high-risk HPVs as they are found to be associated with the development of a number of different cancers. Almost all cervical cancers appear to be driven by HPV infection and HPV is also found in most cancers of the anus and at least half the cancers of the vulva, penis and vagina, and increasingly found in one sub-type of head and neck cancers namely oropharyngeal squamous cell carcinoma. Our understanding of HPVs role in cancer development comes from extensive studies done on cervical cancer and it has just been assumed that HPV plays an identical role in the development of all other cancers arising in the presence of HPV sequences, although this has not been proven. Most invasive cervical cancers have the HPV genome integrated into one or more sites within the human genome. One powerful tool to examine all the sites of HPV integration in a cancer but that also provides a comprehensive view of genomic alterations in that cancer is the use of next generation sequencing of mate-pair libraries produced from the DNA isolated. We will describe how this powerful technology can provide important information about the genomic organization within an individual cancer genome, and how this has demonstrated that HPVs role in oropharyngeal squamous cell carcinoma is distinct from that in cervical cancer. We will also describe why the sequencing of mate-pair libraries could be a powerful clinical tool for the management of patients with a DNA viral etiology and how this could quickly transform the care of these patients.

Human papillomavirus and tonsillar and base of tongue cancer

In 2007, human papillomavirus (HPV) type 16 was recognized as a risk factor by the International Agency for Research on Cancer, for oropharyngeal squamous cell carcinoma (OSCC), where tonsillar and base of tongue cancer (TSCC and BOTSCC) dominate. Furthermore, patients with HPV-positive TSCC and BOTSCC, had a much better clinical outcome than those with corresponding HPV-negative cancer and other head and neck cancer. More specifically, survival was around 80% for HPV-positive TSCC and BOTSCC vs. 40% five-year disease free survival, for the corresponding HPV-negative tumors with conventional radiotherapy and surgery, while this could not be observed for HPV-positive OSCC at other sites. In addition, the past 20-40 years in many Western Countries, the incidence of HPV-positive TSCC and BOTSCC has risen, and >70% are men. This has resulted in a relative increase of patients with HPV-positive TSCC and BOTSCC that may not need the intensified chemo-radiotherapy (with many more severe debilitating side effects) often given today to patients with head and neck cancer. However, before tapering therapy, one needs to enable selection of patients for such treatment, by identifying clinical and molecular markers that together with HPV-positive status will better predict patient prognosis and response to therapy. To conclude, there is a new increasing group of patients with HPV-positive TSCC and BOTSCC with good clinical outcome, where options for better-tailored therapy are needed. For prevention, it would be of benefit to vaccinate both girls and boys against HPV16 infection. For potential future screening the ways to do so need optimizing.

Mobile fiber-optic sensor for detection of oral and cervical cancer in the developing world

Oral and cervical cancers are a growing global health problem that disproportionately impacts women and men living in the developing world. The high death rate in developing countries is largely due to the fact that these countries do not have the appropriate medical infrastructure and resources to support the organized screening and diagnostic programs that are available in the developed world. Diffuse reflectance spectroscopy (DRS) with a fiber-optic probe can noninvasively quantify the optical properties of epithelial tissues and has shown the potential as a cost-effective, easy-to-use, and sensitive tool for diagnosis of early precancerous changes in the cervix and oral cavity. However, current fiber-optic DRS systems have not been designed to be robust and reliable for use in developing countries. They are subject to various sources of systematic or random errors, arising from the uncontrolled probe-tissue interface and lack of real-time calibration, use bulky and expensive optical components, and require extensive training. This chapter describes a portable DRS device that is specifically designed for detection of oral and cervical cancers in resource-poor settings. The device uses an innovative smart fiber-optic probe to eliminate operator bias, state-of-the-art photonics components to reduce size and power consumption, and automated software to reduce the need of operator training. The size and cost of the smart fiber-optic DRS system may be further reduced by incorporating a smartphone based spectrometer.

Human papillomavirus (HPV) and oropharyngeal squamous cell carcinoma

Numerous reports in recent decades have shown that, in addition to smoking and alcohol, human papillomavirus (HPV) is also associated with the development of oropharyngeal squamous cell carcinoma (OPSCC), predominantly in the tonsils and base of the tongue. In 2007, the International Agency on Research against Cancer (IARC) therefore declared HPV to be a risk factor for OPSCC and noted that 80% of those affected are men. In addition, patients with HPV-positive OPSCC, in particular never-smokers, have a much better clinical response to therapy than patients with HPV-negative OPSCC and other head and neck cancers. Most patients with HPV-positive OPSCC may thus not need the increasingly intensive chemo-radiotherapy currently administered today to most patients with head neck cancers and associated with many adverse effects. Furthermore, an increase in the incidence of OPSCC has been observed in many western countries, accompanied by a rise in the proportion of HPV-positive tumors. Patients with HPV-positive OPSCC, like those with cervical cancer, more often have an earlier sexual debut and have more sexual partners. It has therefore been proposed that the increased incidence of OPSCC observed might be due to an epidemic of sexually transmitted HPV. The important issues today regarding this growing cohort of patients with HPV-positive OPSCC are therefore individualized treatment and prevention. More specifically, selected HPV-positive OPSCC patients with biomarkers of good prognosis might be included in randomized trials with less intensive treatment. HPV vaccination should also be considered for boys, in addition to the current recommendations for immunization of girls.

Weight and body mass index in relation to irradiated volume and to overall survival in patients with oropharyngeal cancer: a retrospective cohort study

Background

Weight loss is a common problem in patients with Squamous Cell Carcinoma of the Head and Neck (SCCHN) treated with radiotherapy (RT). The aims of the present study were to determine if treated volume (TV), as a measure of the radiation dose burden, can predict weight loss in patients with oropharyngeal cancer and to analyze weight loss and body mass index (BMI) in the same patient group in relation to 5-year overall survival.

Methods

The ARTSCAN trial is a prospective, randomized, multicenter trial in patients with SCCHN. Nutritional data from the ARTSCAN trial were analyzed retrospectively using univariate and multivariate statistical methods based on information on percentage weight loss from the start of RT up to five months after the termination of RT (study cohort 1, n = 232) and information on patients’ BMI at the start of RT (study cohort 2, n = 203). TV was defined as the volume of the patient receiving at least 95% of the prescribed dose. TV_{64.6 Gy} encompasses macroscopic tumor and TV_{43.7 Gy} elective lymph nodes of the neck.

Results

TV_{64.6 Gy} and TV_{43.7 Gy} were both significantly correlated with higher weight loss up to five months after the termination of RT in study cohort 1 (p < 0.001 for both). BMI at the start of RT was shown to be a prognostic factor for 5-year overall survival in study cohort 2 but weight loss was not. The hazard ratios and 95% confidence intervals were 3.78 (1.46–9.75) and 2.57 (1.43–4.62) in patients with underweight and normal weight, respectively.

Conclusions

TV can predict weight loss during RT in patients with oropharyngeal cancer regardless of clinical stage. A high BMI (>25 kg/m²) at the start of RT is positively associated with survival in patients with oropharyngeal cancer.

Human papillomavirus and oropharyngeal cancer, the epidemics, and significance of additional clinical biomarkers for prediction of response to therapy (Review)

In 2007, the International Agency for Research against Cancer (IARC) recognized human papillomavirus (HPV), especially HPV16, besides smoking and alcohol, as a risk factor for oropharyngeal squamous cell carcinoma (OPSCC), where tonsillar and base of tongue cancer dominate. Moreover, during the past decade, in many Western countries, a sharp rise in the incidence of OPSCC, more specifically of HPV-positive OPSCC has been observed. Notably, patients with HPV-positive OPSCC, where the majority are men, particularly never-smokers have a better clinical outcome than patients with HPV-negative OPSCC and other head neck cancer (roughly 80 vs. 40% disease-free survival with conventional radiotherapy and surgery). This suggests that many patients with HPV-positive OPSCC may not require the more aggressive intensified chemo-radiotherapy given to head neck cancer patients today, and could with somewhat tapered treatment maintain excellent survival, avoiding some of the severe side effects along with intensified treatment. However, before de-intensified treatment is administered additional biomarkers are necessary in combination with HPV-positive status in order to predict and select patients that will respond favorably to therapy. In conclusion, noteworthy issues within this field with an increasing cohort of patients with HPV-positive OPSCC are better-tailored therapy and prevention. Patients with HPV-positive OPSCC, with biomarkers for good response to therapy e.g., low MHC class I, or CD44 expression or high numbers of CD8+ tumor infiltrating lymphocytes, could be included in randomized trials with less severe therapy. Furthermore, possibilities to screen for HPV-positive OPSCC and to vaccinate boys against HPV infection should be further investigated.

Correlation of LMP10 expression and clinical outcome in Human Papillomavirus (HPV) positive and HPV-Negative tonsillar and base of tongue cancer

AIM

To examine LMP10 expression and its possible impact on clinical outcome in human papillomavirus (HPV) positive and HPV-negative tonsillar and base of tongue squamous cell carcinoma (TSCC and BOTSCC).

BACKGROUND

Outcome is better in HPV-positive TSCC and BOTSCC compared to matching HPV-negative tumours, with roughly 80% vs. 40% 5-year disease free survival (DFS) with less aggressive treatment than today's chemoradiotherapy. Since current treatment often results in harmful side effects, less intensive therapy, with sustained patient survival would be an attractive alternative. However, other markers together with HPV status are necessary to select patients and for this purpose LMP10 expression is investigated here in parallel to HPV status and clinical outcome.

MATERIALS AND METHODS

From 385 patients diagnosed between 2000 and 2007 at the Karolinska University Hospital, 278 formalin fixed paraffin embedded TSCC and BOTSCC biopsies, with known HPV DNA status, were tested for LMP10 nuclear and cytoplasmic expression (fraction of positive cells and staining intensity). The data was then correlated to clinical outcome.

RESULTS

An absent/low compared to a moderate/high LMP10 nuclear fraction of positive cells was correlated to a better 3-year DFS in the HPV-positive group of patients (log-rank p = 0.005), but not in the HPV-negative group. In the HPV-negative group of patients, in contrast to the HPV-positive group, moderate/high LMP10 cytoplasmic fraction and weak/moderate/high LMP10 cytoplasmic intensity correlated to a better 3-year DFS (p = 0.003 and p = 0.001) and 3-year overall survival (p = 0.001 and 0.009).

CONCLUSION

LMP10 nuclear expression in the HPV-positive group and LMP10 cytoplasmic expression in the HPV-negative group of patients correlated to better clinical outcome.

Feasibility and Efficacy of an Addiction Treatment Program in Patients With Upper Aerodigestive Tract Cancer

BACKGROUND

Continuing to smoke or to drink after the treatment of an upper aerodigestive tract (UADT) cancer is known to worsen the prognosis. We assessed the feasibility and efficacy of an addiction treatment program integrated into the cancer treatment.

METHOD

In four units devoted to UADT tumors, we proposed an addiction treatment to all patients still drinking or smoking at the end of the cancer treatment; the abstinence rate was assessed 6 and 12 months later.

RESULTS

One hundred and sixteen patients were included. Among the 73 patients still drinking and/or smoking at the end of the cancer treatment, 46.6% accepted an addiction treatment. In the latter, abstinence rate was increased, 52.2% versus 31.03% ( p = .07) at M12. In patients both drinking and smoking, addiction treatment doubled the rate of abstinence of both products (31% vs. 14%).

CONCLUSION

Offering addiction treatment to patients with UADT cancer improves abstinence rate and helps maintain long-term withdrawal.

[Primary presentation of non-hodgkin lymphoma. Report of a case]

Lymphomas are the most common non-epithelial tumors of the head and neck and its incidence has increased in recent decades. Around 10% are extranodal lymphomas, and in more than half of the cases are located in Waldeyer's lymphatic ring. The most common presenting symptoms are odynophagia and dysphagia (68%), and symptoms suggestive of oropharyngeal cancer such as cough, hoarseness, earache, feeling of occupation in the back of the mouth, throat or neck. In non-Hodgkin lymphomas in this location, B symptoms (weight loss, fever and sweating) are rare (5%). The histological subtype of each individual lymphoma affects the evaluation, therapy and prognosis.

Comparison of cryotherapy and photodynamic therapy in treatment of oral leukoplakia

Oral leukoplakia is a pre-malignant lesion of the oral mucosa. The aim of this study is to compare the curative effects of photodynamic therapy and cryotherapy in the treatment of oral leukoplakia. The first group, treated by photodynamic therapy (δ-aminolevulinic acid (ALA), 630-635 nm wavelength), consisted of 48 patients suffering from leukoplakia. The second group consisted of 37 patients treated using cryotherapy. Analyses and comparisons of the complete responses, recurrences, numbers of procedures and adverse effects after both PDT and cryotherapy were obtained. In the first group, a complete response was obtained in 35 patients (72.9%), with thirteen recurrences observed (27.1%) over a six-month period. In the second group, a complete response was obtained in 33 patients (89.2%), and recurrence was observed in nine patients (24.3%). Photodynamic therapy and cryotherapy appear to be comparative methods of treatment that may both serve as alternatives for the traditional surgical treatment of oral leukoplakia. The advantages of PDT are connected with minimally invasive and localized character of the treatment and with not damage of collagenous tissue structures, therefore normal cells will repopulate these arrangements. PDT is more convenient for patients, less painful, and more esthetic.

Selective intraarterial chemoradiation therapy for oropharyngeal carcinoma with high-dose cisplatin

PURPOSE

Cisplatin has shown a high tumor response rate among head and neck carcinomas, and the tumor response is related to the cisplatin dosage. The purpose of this study was to evaluate the efficacy and toxicity of selective intraarterial chemoradiation therapy for oropharyngeal carcinomas with high-dose cisplatin.

MATERIALS AND METHODS

This retrospective study consisted of 21 patients with oropharyngeal carcinoma, stages II-IVB, in whom intraarterial chemoradiation therapy was performed between 2000 and 2008. All patients were given two courses of selective intraarterial infusions of cisplatin (300 mg/m(2)), systemic chemotherapy with 5-fluorouracil, and simultaneous radiation therapy (58-61 Gy/30 fractions), with a 1-week rest period.

RESULTS

The 2-year overall survival rate of the 15 patients who completed the therapeutic regimen was 71.3%. The 2-year locoregional control rate and disease-free survival rate were 95.0% and 67.7%, respectively.

CONCLUSION

Selective intraarterial high-dose cisplatin chemotherapy with concomitant radiation therapy shows results similar to those of original methods in terms of survival and locoregional control with a reduction in the number of procedure times.

Oropharyngeal cancer epidemic and human papillomavirus

Patients with HPV-positive cancer were young and lacked traditional risk factors.

Oropharyngeal Cancer Epidemic and HPV

A growing body of research shows that human papillomavirus (HPV) is a common and increasing cause of oropharyngeal squamous cell carcinoma (OSCC). Thus, the International Agency for Research against Cancer has acknowledged HPV as a risk factor for OSCC, in addition to smoking and alcohol consumption. Recently, in Finland, the United Kingdom, the Netherlands, the United States, and Sweden, incidence of OSCC has increased, and an increase in the proportion of HPV-positive tumors was noted. On the basis of these data and reports indicating that patients with HPV-positive cancer have their first sexual experience at a young age and have multiple partners, we postulate that increased incidence of OSCC in the United States and some countries in northern Europe is because of a new, primarily sexually transmitted HPV epidemic. We also suggest that individualized treatment modalities and preventive vaccination should be further explored.

Paraneoplastic encephalomyelitis: Is it an oropharyngeal or a lung cancer complication?

This case report describes a patient with a locally advanced oropharyngeal cancer with a simultaneous paraneoplastic encephalomyelitis. To the best of our knowledge, a paraneoplastic neurological syndrome is a rare complication in head and neck cancer, and has previously not been reported in the literature. One year later, following initial treatment, a small cell lung cancer developed, a tumor frequently associated with this type of paraneoplastic syndrome. The dilemma, therefore, is whether this paraneoplastic symdrome was a secondary complication of the tonsilar concurrent cancer or a metachronous paraneoplastic syndrome prior to small cell lung cancer.

Impact of HPV in Oropharyngeal Cancer

The incidence of oropharyngeal cancers has increased in the western world and Human Papilloma Virus (HPV) has been recognised as a risk factor in the last decades. During the same period the prevalence of HPV in oropharyngeal tumours has increased and HPV has been suggested responsible for the increase. The HPV-positive tumours are today recognized as a distinct subset of head and neck cancers with its own clinopathological and risk profile and have a significantly improved prognosis regardless of treatment strategy. This review summarizes current knowledge regarding human papillomavirus biology, oncogenic mechanisms, risk factors, and impact of treatment.

Observation of the esophagus, pharynx and lingual root by gastrointestinal endoscopy with a percutaneous retrograde approach

AIM: To evaluate the efficacy of retrograde observation of the esophagus, pharynx, larynx and lingual root.

METHODS: With the beagle dog under anesthesia, the anterior wall of the stomach was fixed on the abdominal wall in a similar way to percutaneous endoscopic gastrostomy. The gastrointestinal scope was inserted via a 12 mm laparoscopic port for subsequent retrograde observation from stomach to the oral cavity.

RESULTS: With this technique, direct observation of gastric cardia was possible without restriction. The cervical esophagus was dilated well, also allowing clear observation of the hypopharyngo-esophageal junction. If the tongue was manually pulled out forward, observation of the lingual root was possible.

CONCLUSION: This procedure is easy and effective for pre-treatment evaluation of the feasibility of endoscopic resection in cases of superficial carcinoma of head and neck.

Rehabilitation: long-term physical and functional changes following treatment

OBJECTIVES

To describe the life altering issues that survivors of a head and neck cancer report post treatment and discuss multidimensional rehabilitation approaches.

DATA SOURCES

Published journal articles, literature reviews, research reports, book chapters.

CONCLUSION

Survivors and their family caregivers encounter many changes during the first 3 months following treatment for head and neck cancer, placing them at risk of multiple adjustment difficulties. Progressive weight loss, loss of energy, strength, muscle endurance and decreased functioning severely compromise healthy adjustment and quality of life.

IMPLICATIONS FOR NURSING PRACTICE

Nurses can help patients and family identify survivorship issues to be managed at home. Planning, exploring, coaching, practicing skills with survivors and their family caregivers, providing specific information, and linking them with resources can help them bridge this transition into extended survivorship.

Prognostic Value of FDG-PET in patients with oropharyngeal carcinoma treated with concurrent chemoradiotherapy

Purpose

The purpose of this study was to evaluate the predictive value of 2-deoxy-2-[F-18]fluoro-d-glucose-positron emission tomography (FDG-PET) following concurrent chemoradiotherapy (CRT) on survival in patients with carcinoma of the oropharynx (OPC).

Methods

Eighteen patients with primary OPC who underwent PET pre- and post-CRT were evaluated prospectively for survival. The prognostic performance of post-CRT PET and CT for recurrence was compared.

Results

Patients with positive post-CRT PET exhibited significantly lower 2-year cause-specific survival and disease-free survival (50% vs. 91%, P < 0.05 and 0% vs. 83%, P < 0.0001); however, patients with positive post-CRT CT did not exhibit any significant difference (67% vs. 83%, P = 0.416 and 50% vs. 75%, P = 0.070). Other factors, such as clinical and pre-CRT PET variables, also did not indicate any significant difference. The accuracy of prediction of residual and local recurrence for post-CRT PET and CT (local%/regional%) was 83%/94% and 83%/78%, respectively.

Conclusion

OPC patients with positive post-CRT PET exhibit poor survival. The prognostic accuracy of post-CRT PET is superior to that of CT. The results of post-CRT FDG-PET should be included in the management of the OPC patients.

Recurrence in patients with oral and oropharyngeal squamous cell carcinoma: human papillomavirus and other risk factors

CONCLUSIONS

The results confirm that tumour stage influences the risk of recurrence/second primary tumour (SPT). High-risk human papillomavirus (HPV)-infected patients have a significantly higher risk of recurrence/SPT compared with high-risk HPV-negative patients. High alcohol consumption was associated with a higher risk of recurrence/SPT. In this study, the competing risk of death in intercurrent disease (DICD) was given special consideration.

OBJECTIVES

The aim of the present study was to evaluate whether any of the factors which were found to increase the risk of oral and oropharyngeal squamous cell carcinoma (OOSCC) in previous analyses (smoking tobacco, alcohol, high-risk HPV infection, oral hygiene, missing teeth and dentures) have an influence on recurrence or the occurrence of a new SPT of OOSCC within the first 3 years following diagnosis.

PATIENTS AND METHODS

One hundred and twenty-eight consecutive cases with planned curative treatment, who were part of a population-based case-control study carried out in southern Sweden between September 2000 and January 2004, were included. Only patients for whom the intention was curative treatment were eligible. The cases were followed to the first event of recurrence/SPT, death, loss to follow-up, 30 June 2005 or a maximum of 3 years. Time to the first event of recurrence/SPT was analysed by cumulative incidence, where DICD was a competing risk. Regression was performed on cause-specific hazard rates.

RESULTS

After a median follow-up time of 22 months (range 0-36 months), 30 recurrences, 2 SPT, 12 lost to follow-up and 21 deaths before recurrence or SPT were observed. Tumour stage was associated with both a higher risk of recurrence/SPT and of DICD. In univariate analysis, patients with tonsillar carcinoma had a significantly higher risk of recurrence/SPT than patients with carcinoma at other sites, but there was no difference according to site in multivariate analyses. High alcohol consumption was associated with a higher risk of recurrence/SPT, but not of DICD. There was no increased risk of recurrence/SPT related to smoking, but there was an association between smoking and DICD. High-risk HPV-positive cases had a higher risk of recurrence/SPT, but a lower risk of DICD compared with high-risk HPV-negative cases. This seemingly higher risk should be interpreted by taking the competing risk of DICD into account.

Utility of 18F-fluorodeoxyglucose positron emission tomography in the preoperative staging of squamous cell carcinoma of the oropharynx

BACKGROUND

18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has been reported to be superior to computed tomography (CT)/magnetic resonance imaging (MRI) in the evaluation of head and neck cancers, but little is known about its usefulness in oropharyngeal squamous cell carcinoma (SCC). We therefore compared FDG PET and CT/MRI in the preoperative staging of previously untreated oropharyngeal SCC.

METHODS

Thirty-two consecutive patients with oropharyngeal SCC underwent FDG PET and CT/MRI before surgery. Each method was interpreted separately to assess primary tumor and cervical node status. Their sensitivity and specificity were compared relative to histopathologic analysis.

RESULTS

Histopathology revealed metastases in 29 of 39 dissected neck sides and in 47 of 163 dissected cervical levels. FDG PET had higher sensitivities than CT/MRI for primary tumor detection (25/32 vs. 30/32, P=0.063) and for identification of cervical metastases on neck side (22/29 vs. 28/29, P<0.05) and level-by-level (37/47 vs. 45/47, P<0.05) bases. In contrast, the specificity of the two methods did not differ significantly (P>0.5). FDG PET correctly interpreted the false-negative results of CT/MRI in 6 of 7 primary tumors and 8 of 10 cervical levels.

CONCLUSIONS

The improved preoperative staging of FDG PET may help in planning treatment, but its accuracy is insufficient to replace pathologic staging based on neck dissection.

Critical weight loss in head and neck cancer—prevalence and risk factors at diagnosis: an explorative study

GOALS OF WORK

Critical weight loss (> or =5% in 1 month or > or =10% in 6 months) is a common phenomenon in head and neck cancer patients. It is unknown which complaints are most strongly related to critical weight loss in head and neck cancer patients at the time of diagnosis. The aim of this explorative study was to assess the prevalence of critical weight loss and to analyze risk factors for critical weight loss in head and neck cancer patients before treatment.

MATERIALS AND METHODS

Critical weight loss and factors reducing dietary intake were assessed in 447 patients referred to an ear, nose and throat clinic at the time of diagnosis.

MAIN RESULTS

In total, data of 407 patients were analyzed. Critical weight loss was present in 19% of the patients. Patients with cancer in the hypopharynx, oropharynx/oral cavity and supraglottic larynx had the highest risk for critical weight loss. Loss of appetite, dysphagia/passage difficulties and loss of taste/aversion were significantly (p < 0.05) associated with critical weight loss.

CONCLUSIONS

Already before treatment, critical weight loss is a considerable problem in head and neck cancer patients. Critical weight loss is frequently observed in patients with cancer in the hypopharynx, oropharynx/oral cavity and supraglottic larynx.

Human papillomavirus as a risk factor for the increase in incidence of tonsillar cancer

Smoking and alcohol are well-known etiological factors in tonsillar cancer. However, as in cervical cancer, human papillomavirus (HPV) is currently found in a sizable proportion of tonsillar cancer. Recent reports from the U.S. and Finland show an increase in the incidence of tonsillar cancer, without a parallel rise in smoking and alcohol consumption. This study investigates whether the incidence of tonsillar cancer has also changed in Sweden and whether a possible explanation of the increase is a higher proportion of HPV-positive tonsillar cancer. The incidence of tonsillar cancer between 1970 and 2002 in the Stockholm area was obtained from the Swedish Cancer Registry. In parallel, 203 pretreatment paraffin-embedded tonsillar cancer biopsies taken during 1970-2002 from patients in the Stockholm area were tested for presence of HPV DNA by PCR. The incidence of tonsillar cancer increased 2.8-fold (2.6 in men and 3.5 in women) from 1970 to 2002. During the same period, a significant increase in the proportion of HPV-positive tonsillar cancer cases was observed, as it increased 2.9-fold (p < 0.001). The distribution of HPV-positive cases was 7/30 (23.3%) in the 1970s, 12/42 (29%) in the 1980s, 48/84 (57%) in the 1990s and 32/47 (68%) during 2000-2002. We have demonstrated a highly significant and parallel increase both in the incidence of tonsillar cancer and the proportion of HPV-positive tumors. Hence, HPV may play an important role for the increased incidence of tonsillar cancer. This should definitely influence future preventive strategies as well as treatment for this type of cancer.

Oropharyngeal carcinoma and its treatment in Finland between 1995–1999: a nationwide study

The survival figures for advanced stage oropharyngeal carcinoma (OPC) have remained moderate in spite of radical combined modality treatments. The purpose of this study was to investigate the used treatment approach and the outcome of OPC in a nationwide study. Retrospective clinicopathological data of all patients diagnosed with OPC between 1995 and 1999 at the five university hospitals in Finland were reviewed. All patients had a minimum 4-year follow-up. A total of 168 patients (145 men and 23 women, mean age 59 years; range 28 - 89 years) were included. The T categories were as follows: T1, n =34; T2, n =55; T3, n =40; T4, n =39. One hundred and seventeen (69.6%) patients presented with neck node metastases and three (1.8%) patients with distant metastases. In the majority (61.3%) of the patients the tumor was located in the lateral wall of the oropharynx. In 144 (85.7%) patients the treatment was performed with curative intent. Of these, surgery of the primary tumor was performed in 123 (85.4%) patients, and the defect was reconstructed with a pedicled flap or free tissue transfer in 66 (53.7%) of these patients. A neck dissection (ND) was performed in 86 (69.9%) out of these 123 cases. Surgery was the only treatment modality in 10 (6.9%) patients. Radiation therapy (RT) only (with or without chemotherapy) was given to 21 (14.6%), combined treatment with surgery + radiation therapy (S + RT) to 110 (76.4%) and surgery + chemoradiotherapy (S + CRT) to 3 (2.1%) patients. Overall (OS) 3- and 5-year survival rates were 58 and 45%, respectively. Disease-specific (DSS) 5-year survival rates by T-class for the patients treated with curative intent were as follows: T1, 77%; T2, 70%; T3, 66%; T4, 53%. The variable treatment approach, the frequent locoregional recurrences and the moderate survival point out the need to consider new strategies in the management of OPC.

Human papillomavirus type 16 in head and neck carcinogenesis

The aetiology of squamous cell carcinomas of the head and neck (HNSCC) is multifactorial. Oncogenic human papillomaviruses (HPVs), a causative agent in uterine cervical cancer, have also been repeatedly detected in HNSCC, especially in squamous cell carcinomas of tonsils. Approximately half the HPV DNA-positive HNSCC contain detectable E6/E7 transcripts with wild-type p53, reduced pRb and overexpressed p16 in the tumours. HPV-16 is the predominant type and exists in episomal, integrated, or mixed forms. Tonsillar carcinomas have a remarkably higher viral load than carcinomas at other sites of the head and neck region. HPV-16 DNA has also been detected in tumour-free tonsils. Infection by oncogenic HPVs is a necessary but not a sufficient cause of cancers. Studies on the molecular mechanisms underlying HPV-associated carcinogenesis are difficult, because HPV is not easy to propagate in vitro. HPV-immortalised human tonsillar epithelial cell lines may provide an in vitro model to study co-factors for the HPV-associated tonsillar cancers and to test the effects of anti-viral and anti-tumour agents.

Presence and Influence of Human Papillomaviruses (HPV) in Tonsillar Cancer

Tonsillar cancer is the most common of the oropharyngeal carcinomas and human papillomavirus (HPV) has been found to be present in approximately half of all cases. Patients with HPV-positive tonsillar cancer have been observed to have a better clinical outcome than patients with HPV-negative tonsillar cancer. Moreover, patients with tonsillar cancer and a high viral load have been shown to have a better clinical outcome, including increased survival, compared to patients with a lower HPV load in their tumors. Recent findings show that HPV-positive tumors are not more radiosensitive and do not have fewer chromosomal aberrations than HPV-negative tumors, although some chromosomal differences may exist between HPV-positive and -negative tonsillar tumors. Current experimental and clinical data indicate that an active antiviral cellular immune response may contribute to this better clinical outcome. These data are also in line with the findings that the frequency of tonsillar cancer is increased in patients with an impaired cellular immune system. Thus, therapeutic and preventive HPV-16 antiviral immune vaccination trials may be worthwhile, not only in cervical cancer, but also in tonsillar cancer.