New treatment strategies for HPV-positive head and neck cancer

Integrative analysis in head and neck cancer reveals distinct role of miRNome and methylome as tumour epigenetic drivers

Head and neck cancer is the sixth most common malignancy worldwide, with the relatively low 5-year survival rate, mainly because it is diagnosed at a late stage. Infection with HPV is a well known aetiology, which affects the nature of these cancers and patients' survival. Besides, it is considered that the main driving force for this type of cancer could be epigenetics. In this study we aimed to find potential epigenetic biomarkers, by integrating miRNome, methylome, and transcriptome analyses. From the fresh head and neck cancer tissue samples, we chose a group for miRNome, methylome and transcriptome profiling, in comparison to adequate control samples. Bioinformatics analyses are performed in R v4.2.2. Count normalisation and group differential expression for mRNA and the previously obtained miRNA count data was performed with DESeq2 v1.36. Gene set enrichment analysis was performed and visualised using gProfiler2 v0.2.1 Identification of miRNA targets was performed by querying in miRTarBase using multiMiR v1.18.0. Annotation of CpG sites merging into islands was obtained from RnBeads.hg19 v1.28.0. package. For the integrative analysis we performed kmeans clustering using stats v4.2.2 package, using 8-12 clusters and nstart 100. We found that transcriptome analysis divides samples into cancers and controls clusters, with no relation to HPV status or cancer anatomical location. Differentially expressed genes (n = 2781) were predominantly associated with signalling pathways of tumour progression. We identified a cluster of genes under the control of the transcription factor E2F that are significantly underexpressed in cancer tissue, as well as T cell immunity genes and genes related to regulation of transcription. Among overexpressed genes in tumours we found those that belong to cell cycle regulation and vasculature. A small number of genes were found significantly differentially expressed in HPV-positive versus HPV-negative tumours (for example NEFH, ZFR2, TAF7L, ZNF541, and TYMS). In this comprehensive study on an overlapping set of samples where the integration of miRNome, methylome and transcriptome analysis were performed for head and neck cancer, we demonstrated that the majority of genes were associated exclusively with miRNome or methylome and, to a lesser extent, under the control of both epigenetic mechanisms.

Is an oropharyngeal HPV infection more frequently detectable in women with a genital HPV infection?

PURPOSE

If not eliminated by the immune system and persisting over years, oropharyngeal high-risk HPV infection can lead to cancer development in the oropharynx. HPV infection is very commonly found in the genital region and can serve as an HPV reservoir. In this study, we investigate whether women with a genital HPV infection are at a higher risk of harboring an undetected oropharyngeal HPV infection via genital-oropharyngeal transmission.

METHODS

Women presenting for routine gynecological checkups were included in this study. All participants received an HPV brush test from the genital region as well as from the oropharynx. Additionally, probable risk factors for an HPV infection were assessed in a structured questionnaire.

RESULTS

142 women were included in this study. The rate of oropharyngeal HPV infection was low with 2/142 (1,4%) women positive for a low-risk HPV genotype. In the genital brush test, 54/142 (38%) women were tested HPV positive of which 41/142 (29%) were positive for a high-risk HPV genotype.

CONCLUSIONS

The rate of an oropharyngeal HPV detection in our population was low with 2/142 women harboring a low-risk HPV infection.

NCCN Guidelines® Insights: Head and Neck Cancers, Version 1.2022

The NCCN Guidelines for Head and Neck Cancers address tumors arising in the oral cavity (including mucosal lip), pharynx, larynx, and paranasal sinuses. Occult primary cancer, salivary gland cancer, and mucosal melanoma (MM) are also addressed. The specific site of disease, stage, and pathologic findings guide treatment (eg, the appropriate surgical procedure, radiation targets, dose and fractionation of radiation, indications for systemic therapy). The NCCN Head and Neck Cancers Panel meets at least annually to review comments from reviewers within their institutions, examine relevant new data from publications and abstracts, and reevaluate and update their recommendations. These NCCN Guidelines Insights summarize the panel's most recent recommendations regarding management of HPV-positive oropharynx cancer and ongoing research in this area.

Trends in Cancer Treatment for Oral Cavity, Oropharynx, and Larynx in 2016 Versus 2009: SEER Patterns of Care Studies

PURPOSE

To determine if there was a higher percentage of patients treated surgically and with advanced radiotherapy in 2016 (N = 897) versus 2009 (N = 1136), the patient and tumor characteristics associated with surgical care and advanced radiotherapy, and if chemotherapy or targeted agent use varied over time for squamous cell carcinoma of the head and neck.

METHODS

We utilized Surveillance Epidemiology and End Results Patterns of Care datasets. Rao-Scott Chi-square tests and logistic regressions were applied to determine differences in surgery, advanced radiotherapy (RT), and chemotherapy by year.

RESULTS

There was a lower prevalence of surgery only treatment in 2016 versus 2009 with exception of oral cavity stages IVB/IVC and unknown, and larynx stage unknown. Advanced RT was more common in 2016 for patients receiving definitive RT among all sites, excluding stages I/II glottic larynx. Among each site (oral cavity, oropharynx, and larynx) lower stage was associated with increased odds of surgery. Among each site, advanced RT was more common in patients receiving definitive versus postoperative RT. For the larynx site, 2016 versus 2009 was associated with greater odds of advanced RT. Systemic treatment with fluorouracil, taxanes, or cetuximab was less prevalent in 2016.

CONCLUSION

In 2016 versus 2009, there was largely not a higher percentage of patients treated surgically. There was a higher prevalence of advanced RT for definitive care. Further investigations of these patterns are needed, including trend analysis.

Phytochemicals as Potential Chemopreventive and Chemotherapeutic Agents for Emerging Human Papillomavirus-Driven Head and Neck Cancer: Current Evidence and Future Prospects

Head and neck cancer (HNC) usually arises from squamous cells of the upper aerodigestive tract that line the mucosal surface in the head and neck region. In India, HNC is common in males, and it is the sixth most common cancer globally. Conventionally, HNC attributes to the use of alcohol or chewing tobacco. Over the past four decades, portions of human papillomavirus (HPV)-positive HNC are increasing at an alarming rate. Identification based on the etiological factors and molecular signatures demonstrates that these neoplastic lesions belong to a distinct category that differs in pathological characteristics and therapeutic response. Slow development in HNC therapeutics has resulted in a low 5-year survival rate in the last two decades. Interestingly, HPV-positive HNC has shown better outcomes following conservative treatments and immunotherapies. This raises demand to have a pre-therapy assessment of HPV status to decide the treatment strategy. Moreover, there is no HPV-specific treatment for HPV-positive HNC patients. Accumulating evidence suggests that phytochemicals are promising leads against HNC and show potential as adjuvants to chemoradiotherapy in HNC. However, only a few of these phytochemicals target HPV. The aim of the present article was to collate data on various leading phytochemicals that have shown promising results in the prevention and treatment of HNC in general and HPV-driven HNC. The review explores the possibility of using these leads against HPV-positive tumors as some of the signaling pathways are common. The review also addresses various challenges in the field that prevent their use in clinical settings.

Metabolomics of Oral/Head and Neck Cancer

Oral/head and neck cancer is the sixth most common human malignancies in the world. Despite the treatment advances in surgery, chemotherapy, and radiotherapy, the patient survival has not been significantly improved in the past several decades. As a new methodological approach, metabolomics may help reveal the metabolic reprogramming mechanisms underlying head and neck cancer cell proliferation, invasion, and metastasis and may be used to identify metabolite biomarkers for clinical applications of the disease. In this chapter, we briefly review recent metabolomic applications in head and neck cancer.

Longitudinal characterization of the tumoral microbiome during radiotherapy in HPV-associated oropharynx cancer

PURPOSE

To describe the baseline and serial tumor microbiome in HPV-associated oropharynx cancer (OPC) over the course of radiotherapy (RT).

METHODS

Patients with newly diagnosed HPV-associated OPC treated with definitive radiotherapy +/- concurrent chemotherapy were enrolled in this prospective study. Using 16S rRNA gene sequencing, dynamic changes in the tumor site microbiome during RT were investigated. Surface tumor samples were obtained before RT and at week 1, 3 and 5 of RT. Radiological primary tumor response at mid-treatment was categorized as complete (CR) or partial (PR).

RESULTS

Ten patients were enrolled, but 9 patients were included in the final analysis. Mean age was 62 years (range: 51-71). As per AJCC 8th Ed, 56%, 22% and 22% of patients had stage I, II and III, respectively. At 4-weeks, 6 patients had CR and 3 patients had PR; at follow-up imaging post treatment, all patients had CR. The baseline diversity of the tumoral versus buccal microbiome was not statistically different. For the entire cohort, alpha diversity was significantly decreased over the course of treatment (p = 0.04). There was a significant alteration in the bacterial community within the first week of radiation. Baseline tumor alpha diversity of patients with CR was significantly higher than those with PR (p = 0.03). While patients with CR had significant reduction in diversity over the course of radiation (p = 0.01), the diversity remained unchanged in patients with PR. Patients with history of smoking had significantly increased abundance of  Kingella (0.05) and lower abundance of Stomatobaculum (p = 0.03) compared to never smokers.

CONCLUSIONS

The tumor microbiome of HPV-associated OPC exhibits reduced alpha diversity and altered taxa abundance over the course of radiotherapy. The baseline bacterial profiles of smokers vs. non-smokers were inherently different. Baseline tumor alpha diversity of patients with CR was higher than patients with PR, suggesting that the microbiome deserves further investigation as a biomarker of radiation response.

[Tumor biology of oropharyngeal carcinoma]

BACKGROUND

Etiologically, oropharyngeal squamous cell carcinoma (OPSCC) can be divided into OPSCC caused by noxious agents and human papillomavirus (HPV)-driven carcinoma. These types differ with regard to clinical features and prognosis-differences which are rooted in the underlying molecular biology of the tumor.

OBJECTIVE

The aim of this work is to provide an overview of the molecular biological characteristics of the genetics, epigenetics, and immunology of OPSCC.

MATERIALS AND METHODS

A literature review was performed on a selection of genetic, epigenetic, and immunological factors characterizing OPSCC.

RESULTS

The understanding of genetic aberrations and their consequences for cancerogenesis and tumor biology is increasing. Epigenetic phenomena are complementing functional relationships. However, epigenetic mechanisms of gene regulation are complex and much research is still required in this field. Immunological aspects of cancer molecular biology have moved into the focus in light of recent advances in the field of immunotherapy.

CONCLUSION

The tumor biology of OPSCC is primarily defined by its HPV status. Additionally, HPV-independent genetic, epigenetic, and immunological signatures are being defined. From these advances, rationales for new treatment concepts may evolve.

HPV-Induced Oropharyngeal Cancer and the Role of the E7 Oncoprotein Detection via Brush Test

Background: High risk human papillomavirus (hr-HPV)-associated oropharyngeal cancers (OPCs) are characterized by significantly better therapy responses. In order to implement a de-escalated treatment strategy for this tumor entity, it is highly crucial to accurately distinguish HPV-associated OPCs from non-HPV-associated ones. Methods: In this prospective study, 56 patients with histologically confirmed OPC were evaluated. A commercially available sandwich ELISA test system was used for the detection of hr-HPV E7 oncoprotein targeting the genotypes 16, 18 and 45. Results were presented as optical density. Positivity for HPV DNA and p16 immunohistochemistry (IHC) was taken as the reference method. Results: E7 positivity was significantly associated with the reference method (p = 0.048). The sensitivity, specificity, positive predictive value and negative predictive value for the E7 oncoptotein was 60.9% (95% CI 38.5 to 80.3%), 66.7% (95% CI 46% to 83.5%), 64.2% (95% CI 49.4 to 77.4%) and 63.01% (95% CI 48.9–75.2%), respectively, for the cutoff provided by the manufacturer. Conclusions: We found a significant association between E7 oncoprotein detection and the currently used combination. We believe that the use of the ELISA based E7 antigen test could be a valuable addition in cases of ambiguous findings and may be used in combination with other techniques to distinguish between HPV-driven and non-HPV-driven OPCs. However, the low sensitivity of the assay coupled with the small sample size in our study may represent a limitation. We recommend that future larger studies elucidate the diagnostic value of the E7 brush test.

Insurance Status as a Predictor of Treatment in Human Papillomavirus Positive Oropharyngeal Cancer

OBJECTIVES

The link between human papillomavirus (HPV) and oropharyngeal cancer (OPC) is well known. Locally advanced, HPV-positive OPC (HPV OPC) can be treated with either chemoradiation or primary surgery with or without adjuvant therapy. Head and neck cancer patients with government insurance or uninsured have been shown to have worse prognosis than similar patients with private insurance. In this study, we aimed to determine if insurance status would predict treatment modality in patients with HPV OPC.

STUDY DESIGN

A retrospective analysis using the National Cancer Database (NCDB).

METHODS

The National Cancer Database was used to identify patients with HPV OPC who underwent primary surgery or primary chemoradiation from 2010-2015. Insurance status was categorized as government, private, or no insurance. The relationship between insurance status and treatment was investigated using Chi square and multivariate regression models. Kaplan-Meier analyses were performed comparing overall survival (OS) by insurance status.

RESULTS

There were 10,606 patients were included. There was a statistically significant correlation between insurance status and primary treatment modality for HPV OPC (P < .001). Patients with government insurance were 19.3% less likely to undergo surgery and uninsured patients were 36.9% less likely to undergo primary surgery when compared to those with private insurance (P < .001), even after correcting for TNM stage in multivariate analysis. There was an improved 5-year OS for patients with private insurance (86.6%) versus both government insurance (68.4%) and no insurance (69.9%) (P < .001).

CONCLUSIONS

Patients with private insurance are more likely to undergo primary surgery in HPV OPC and have improved overall survival.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:776-781, 2021.

The Role of HPV and Non-HPV Sexually Transmitted Infections in Patients with Oropharyngeal Carcinoma: A Case Control Study

Background: Certain high-risk (hr) types of human papillomavirus (HPV) can cause cervical cancer in women and penile cancer in men. Hr-HPV can also cause cancers of the oropharynx and anus in both sexes. In the anal and cervical region, a contribution of co-infections with Ureaplasma spp. on the persistence of the hr-HPV infection by a profound inflammatory state is suggested. Here, we investigated if non-HPV sexually transmitted infections are associated with oropharyngeal carcinoma (OPC). Materials and Methods: In this case-control study, a brush test directly from the tumor surface of OPC patients (study group) and from the oropharynx of healthy volunteers (control group), both groups matching in age and sex, was performed. HPV subtypes were detected using a commercially available test kit. For non-HPV sexually transmitted infections (Ureaplasma spp., Chlamydia trachomatis, Mycoplasma hominis, and Mycoplasma genitalium), a multiplex nucleic acid amplification approach was performed. Results: In the study group, 96 patients (23 female/73 male), with histologically confirmed OPC and in the control group 112 patients (19 female/93 male), were included. Oropharyngeal hr-HPV-positivity was detected in 68% (65/96 patients) of the study group and 1.8% (2/112 patients) of the control group (p < 0.001). In three patients in the study group, Ureaplasma spp. was detected, whereas no patient was Ureaplasma spp. positive in the control group (p = 0.097). Chlamydia trachomatis, Mycoplasma hominis, and Mycoplasma genitalium were negative in both groups. Conclusion: Based on the current study, the prevalence of oropharyngeal Ureaplasma spp. among patients with OPC is low and does not support a role in oropharyngeal cancer. However, the detection of the pathogen only among OPC patients but not in the healthy individuals might indicate a potential role and needs further elucidation.

Management of HPV-Related Squamous Cell Carcinoma of the Head and Neck: Pitfalls and Caveat

Head and neck squamous cell carcinomas (HNSCCs) are a very heterogeneous group of malignancies arising from the upper aerodigestive tract. They show different clinical behaviors depending on their origin site and genetics. Several data support the existence of at least two genetically different types of HNSCC, one virus-related and the other alcohol and/or tobacco and oral trauma-related, which show both clinical and biological opposite features. In fact, human papillomavirus (HPV)-related HNSCCs, which are mainly located in the oropharynx, are characterized by better prognosis and response to therapies when compared to HPV-negative HNSCCs. Interestingly, virus-related HNSCC has shown a better response to conservative (nonsurgical) treatments and immunotherapy, opening questions about the possibility to perform a pretherapy assessment which could totally guide the treatment strategy. In this review, we summarize molecular differences and similarities between HPV-positive and HPV-negative HNSCC, highlighting their impact on clinical behavior and on therapeutic strategies.

Molecular mechanisms underlying increased radiosensitivity in human papillomavirus-associated oropharyngeal squamous cell carcinoma

Oropharyngeal squamous cell carcinoma (OPSCC) is an important type of head and neck squamous cell carcinoma (HNSCC). The traditional risk factors for OPSCC include carcinogen intake, smoking, alcohol consumption, and lifestyle. In recent years, cases of human papillomavirus (HPV)-related OPSCC have gradually increased. At present, HPV-related OPSCC in developed Western countries comprise up to 90% of all OPSCC cases, while in other developing countries, the proportion of HPV-related OPSCC cases is also gradually increasing. Compared with HPV-negative OPSCC, HPV-positive OPSCC patients have better overall survival rates and local control rates and this improved prognosis may be related to the increased radiosensitivity of HPV-positive tumors. Due to this more favorable prognosis, many downgraded treatment schemes are gradually emerging, including simple radiotherapy instead of concurrent radiotherapy or reduced radiotherapy dose. However, there is insufficient theoretical basis for such schemes. Some studies have shown that delayed repair of DNA damage after radiation, G2/M arrest, increased hypoxia, and decreased proliferation capacity are the main reasons for the increased radiosensitivity of HPV-positive tumor cells. In this review, we discuss the four principles of tumor cell damage caused by radiation, including repair, reoxygenation, redistribution, and regeneration in order to reveal the mechanism whereby HPV increases the radiosensitivity of tumor cells. An attempt was made to provide sufficient information to facilitate more individualized treatment for HPV-positive OPSCC patients, under the premise of good tumor control.

Undifferentiated carcinoma of the oral tongue treated with cetuximab: A case report

Undifferentiated carcinoma of the oral cavity is a rare and possibly fatal malignant neoplasm. We present here a case of undifferentiated carcinoma of the oral tongue, which responded well to chemotherapy with cisplatin, 5-fluorouracil, and cetuximab. A 59-year-old man was referred to our hospital for a large tumor of the tongue. Physical examination revealed an ulcerative tumor, approximately 50 mm in diameter, on the right edge of the tongue and swelling of multiple cervical lymph nodes; therefore, the clinical diagnosis was tongue cancer (T4aN2bM0). The histological diagnosis from a biopsy specimen was undifferentiated carcinoma; we tested the sample for human papilloma virus immunoreactivity, which was positive. The patient then underwent chemotherapy with cisplatin, 5-fluorouracil and cetuximab. The tumor's size decreased markedly after two courses of chemotherapy, but the treatment was stopped due to the patient' various mental problems and pneumonia; he died 6 months after the initial visit. Our encounter with this patient suggests that cetuximab treatment is a good option for HPV-positive undifferentiated carcinoma of the oral tongue.

Roles of Ki-67 and p16 as biomarkers for unknown primary head and neck squamous cell carcinoma

PURPOSE

Treatment guidelines have not been established for unknown primary head and neck squamous cell carcinoma (SCC). For these patients, chemoradiotherapy (CRT) can provide a better prognosis than that for patients with other head and neck cancers. The presence of HPV in the tumor is associated with a better outcome. However, not all patients with HPV-positive unknown primary head and neck SCC experience good treatment outcomes in actual clinical settings.

METHODS

We thus retrospectively determined the Ki-67 proliferation index and p16 expression status to assess the associations of these parameters with treatment outcomes of patients with unknown primary head and neck SCC.

RESULTS

The subjects were 13 patients who underwent CRT after surgery or excision biopsy between 1999 and 2016. The 2- and 5-year overall survival (OS) rate was 76.9% and 68.4%, respectively. The prognostic factor was age. There was no significant difference in survival between patients with a high Ki-67 vs. low Ki-67 or between patients with p16-positive vs. p16-negative metastases OS. However, all p16-positive patients with low Ki-67 showed good locoregional control.

CONCLUSIONS

The combination of ki67 expression and p16 expression status may allow prediction of local control more accurately than p16 expression status alone.

Review of surgical resection and reconstruction in head and neck cancer. Traditional versus current concepts

This review summarizes the development of head and neck cancer resection and reconstruction. The developments in the treatment of cancer patients are reflected in their surgical outcomes, in addition to functional and aesthetic improvements. New technologies, such as surgical simulation and planning, minimally invasive surgery, and microsurgery have been added to the field to improve surgical resection of the tumor and reconstruction. The field is still growing to optimize the management of head and neck cancer.

Evidence-based sizing of non-inferiority trials using decision models

Background

There are significant challenges to the successful conduct of non-inferiority trials because they require large numbers to demonstrate that an alternative intervention is “not too much worse” than the standard. In this paper, we present a novel strategy for designing non-inferiority trials using an approach for determining the appropriate non-inferiority margin (δ), which explicitly balances the benefits of interventions in the two arms of the study (e.g. lower recurrence rate or better survival) with the burden of interventions (e.g. toxicity, pain), and early and late-term morbidity.

Methods

We use a decision analytic approach to simulate a trial using a fixed value for the trial outcome of interest (e.g. cancer incidence or recurrence) under the standard intervention (p_S) and systematically varying the incidence of the outcome in the alternative intervention (p_A). The non-inferiority margin, p_A – p_S = δ, is reached when the lower event rate of the standard therapy counterbalances the higher event rate but improved morbidity burden of the alternative. We consider the appropriate non-inferiority margin as the tipping point at which the quality-adjusted life-years saved in the two arms are equal.

Results

Using the European Polyp Surveillance non-inferiority trial as an example, our decision analytic approach suggests an appropriate non-inferiority margin, defined here as the difference between the two study arms in the 10-year risk of being diagnosed with colorectal cancer, of 0.42% rather than the 0.50% used to design the trial. The size of the non-inferiority margin was smaller for higher assumed burden of colonoscopies.

Conclusions

The example demonstrates that applying our proposed method appears feasible in real-world settings and offers the benefits of more explicit and rigorous quantification of the various considerations relevant for determining a non-inferiority margin and associated trial sample size.

International Endocervical Adenocarcinoma Criteria and Classification: Validation and Interobserver Reproducibility

The current World Health Organization (WHO) classification for endocervical adenocarcinoma (EA) is based on descriptive morphologic characteristics; however, it does not fully reflect our current knowledge of the diverse pathogenesis of cervical glandular neoplasia. A novel classification system, the International Endocervical Adenocarcinoma Criteria and Classification (IECC), which incorporates etiology and biological behavior into the morphologic scheme, has been recently proposed. We aimed to validate the IECC by assessing its interobserver reproducibility in comparison to the WHO system. A cohort of 75 EAs was reviewed independently by 7 gynecologic pathologists and categorized following IECC and WHO criteria based on hematoxylin and eosin material alone and after immunohistochemistry results for p16, PR, p53, Napsin-A, vimentin, CDX2, and GATA3 were provided. Human papillomavirus (HPV) in situ hybridization and polymerase chain reaction results were compared with consensus diagnoses. IECC was superior to WHO in terms of interobserver agreement with κ=0.46 versus 0.3, respectively, on hematoxylin and eosin review and κ=0.51 versus 0.33, respectively, with immunohistochemistry. Under the IECC, 73 (97%) of EAs had majority agreement (≥4 reviewers in agreement) whereas 42 (56%) had perfect agreement (7/7 reviewers in agreement). Conversely, WHO showed majority agreement in 56 (75%) and perfect agreement in only 7 (10%) EAs. Reproducibility was poor in HPV-related WHO types (usual κ=0.36, mucinous not otherwise specified κ=0.13, intestinal κ=0.31, villoglandular κ=0.21) and good in major HPV-unrelated categories (gastric type κ=0.63, clear cell κ=0.81, mesonephric κ=0.5). Classification as per the IECC had excellent correlation with HPV status (by RNA in situ hybridization or polymerase chain reaction). We have shown that the IECC has superior interobserver agreement compared with the WHO classification system, and that distinction between HPV-related and HPV-unrelated EA can be made with good reproducibility and excellent prediction of HPV status. WHO morphologic variants of HPV-related EA are poorly reproducible. Conversely, agreement is high among important high-risk HPV-unrelated subtypes. Thus, our results further support replacing the current WHO classification with the IECC.

Magnetic Resonance-based Response Assessment and Dose Adaptation in Human Papilloma Virus Positive Tumors of the Oropharynx treated with Radiotherapy (MR-ADAPTOR): An R-IDEAL stage 2a-2b/Bayesian phase II trial

BACKGROUND

Current standard radiotherapy for oropharynx cancer (OPC) is associated with high rates of severe toxicities, shown to adversely impact patients' quality of life. Given excellent outcomes of human papilloma virus (HPV)-associated OPC and long-term survival of these typically young patients, treatment de-intensification aimed at improving survivorship while maintaining excellent disease control is now a central concern. The recent implementation of magnetic resonance image - guided radiotherapy (MRgRT) systems allows for individual tumor response assessment during treatment and offers possibility of personalized dose-reduction. In this 2-stage Bayesian phase II study, we propose to examine weekly radiotherapy dose-adaptation based on magnetic resonance imaging (MRI) evaluated tumor response. Individual patient's plan will be designed to optimize dose reduction to organs at risk and minimize locoregional failure probability based on serial MRI during RT. Our primary aim is to assess the non-inferiority of MRgRT dose adaptation for patients with low risk HPV-associated OPC compared to historical control, as measured by Bayesian posterior probability of locoregional control (LRC).

METHODS

Patients with T1-2 N0-2b (as per AJCC 7th Edition) HPV-positive OPC, with lymph node <3 cm and <10 pack-year smoking history planned for curative radiotherapy alone to a dose of 70 Gy in 33 fractions will be eligible. All patients will undergo pre-treatment MRI and at least weekly intra-treatment MRI. Patients undergoing MRgRT will have weekly adaptation of high dose planning target volume based on gross tumor volume response. The stage 1 of this study will enroll 15 patients to MRgRT dose adaptation. If LRC at 6 months with MRgRT dose adaptation is found sufficiently safe as per the Bayesian model, stage 2 of the protocol will expand enrollment to an additional 60 patients, randomized to either MRgRT or standard IMRT.

DISCUSSION

Multiple methods for safe treatment de-escalation in patients with HPV-positive OPC are currently being studied. By leveraging the ability of advanced MRI techniques to visualize tumor and soft tissues through the course of treatment, this protocol proposes a workflow for safe personalized radiation dose-reduction in good responders with radiosensitive tumors, while ensuring tumoricidal dose to more radioresistant tumors. MRgRT dose adaptation could translate in reduced long term radiation toxicities and improved survivorship while maintaining excellent LRC outcomes in favorable OPC.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT03224000; Registration date: 07/21/2017.

Recent advances in the understanding and management of oropharyngeal cancer

Oropharyngeal squamous cell carcinoma (OPSCC) is an increasing health problem in the developing and developed world. In recent years, there have been major changes in the treatment paradigms for OPSCC. This is because of a number of reasons: the understanding and discovery of a new viral etiology (the human papillomavirus [HPV]), changes in practice patterns owing to advances in radiotherapy, and then an organ preservation strategy with the increased use of chemotherapy. Next came the development of new surgical technologies and the emergence of a new treatment modality, immunotherapy. In this article, we discuss the evolution of OPSCC treatments, starting with the traditional tobacco era. Treatment paradigms then evolved during the organ preservation era, the HPV era, and the minimally invasive surgery era. We are currently in the immunotherapy era, with a number of new drugs becoming available both on trial and by approval for use in the clinical setting for head and neck cancer patients. We discuss a number of trials and the reasons behind attempts at both treatment escalation and treatment de-escalation.

Human papillomavirus prevalence and clinicopathological associations in oropharyngeal squamous cell carcinoma in the Lebanese population

OBJECTIVES

To evaluate for the first time the prevalence of human papillomavirus in oropharyngeal squamous cell carcinoma in a Middle-Eastern population, and to determine associations between human papillomavirus profiles and clinicopathological characteristics.

METHODS

A retrospective chart review was conducted of all patients treated for oropharyngeal squamous cell carcinoma at the Hotel Dieu de France University Hospital (Beirut, Lebanon) between January 2010 and 2016. Existing formalin-fixed paraffin-embedded tumour samples were analysed. Human papillomavirus DNA viral load and p16 expression were evaluated using polymerase chain reaction and immunohistochemistry respectively.

RESULTS

Thirty patients (mean age of 60 years) were included. Twenty-seven per cent of patients were p16-positive/human papillomavirus DNA positive, 53 per cent were p16-negative/human papillomavirus DNA negative and 20 per cent were p16-positive/human papillomavirus DNA negative. Human papillomavirus 16 was the most frequent subtype (75 per cent). Smoking and alcohol consumption were significantly lower in the human papillomavirus positive group compared to the human papillomavirus negative group (p = 0.049 and 0.004, respectively).

CONCLUSION

Human papillomavirus rate was lower than reported rates in Western populations. Possible explanations include differences in social and cultural behaviours.

Prospective in silico study of the feasibility and dosimetric advantages of MRI-guided dose adaptation for human papillomavirus positive oropharyngeal cancer patients compared with standard IMRT

PURPOSE

We aim to determine the feasibility and dosimetric benefits of a novel MRI-guided IMRT dose-adaption strategy for human papillomavirus positive (HPV+) oropharyngeal squamous cell carcinoma (OPC).

MATERIALS/METHODS

Patients with locally advanced HPV+ OPC underwent pre-treatment and in-treatment MRIs every two weeks using RT immobilization setup. For each patient, two IMRT plans were created (i.e. standard and adaptive). The prescription dose for the standard plans was 2.12 Gy/fx for 33 fractions to the initial PTV. For adaptive plans, a new PTVadaptive was generated based on serial MRIs in case of detectable tumor shrinkage. Prescription dose to PTVadaptive was 2.12 Gy/fx to allow for maximum dose to the residual disease. Any previously involved volumes received minimally a floor dose of 50.16 Gy. Uninvolved elective nodal volumes were prescribed 50.16 Gy in 1.52 Gy/fx. Dosimetric parameters of organs at risk (OARs) were recorded for standard vs. adaptive plans. Normal tissue complication probability (NTCP) for toxicity endpoints was calculated using literature-derived multivariate logistic regression models.

RESULTS

Five patients were included in this pilot study, 3 men and 2 women. Median age was 58 years (range 45-69). Three tumors originated at the tonsillar fossa and two at the base of tongue. The average dose to 95% of initial PTV volume was 70.7 Gy (SD,0.3) for standard plans vs. 58.5 Gy (SD,2.0) for adaptive plans. The majority of OARs showed decrease in dosimetric parameters using adaptive plans vs. standard plans, particularly swallowing related structures. The average reduction in the probability of developing dysphagia ≥ grade2, feeding tube persistence at 6-month post-treatment and hypothyroidism at 1-year post-treatment was 11%, 4%, and 5%, respectively. The probability of xerostomia at 6-month was only reduced by 1% for adaptive plans vs. standard IMRT.

CONCLUSION

These in silico results showed that the proposed MRI-guided adaptive approach is technically feasible and advantageous in reducing dose to OARs, especially swallowing musculature.

Detailed analysis of adenosine A2a receptor (ADORA2A) and CD73 (5'-nucleotidase, ecto, NT5E) methylation and gene expression in head and neck squamous cell carcinoma patients

Background: The adenosine A2a receptor (A2aR) and the adenosine synthesizing enzyme CD73 have recently evolved as a novel immunotherapeutic target. However, little is known about epigenetic modification of the encoding genes ADORA2A and NT5E. Methods: In the present study, we evaluated methylation at 23 loci of ADORA2A and 17 loci of NT5E with regard to transcriptional activity, human papilloma virus (HPV) status, immune cell infiltration, and outcome in a cohort of 279 head and neck squamous carcinoma (HNSCC) patients obtained from The Cancer Genome Atlas (TCGA). Methylation and mRNA expression were generated by the Infinium HumanMethylation450 BeadChip and Illumina HiSeq 2000 RNA Sequencing Version 2 analysis (Illumina, Inc., San Diego, CA, USA). HPV status was assessed by RNA-Seq data analysis of the viral genes E6 and E7. Results: Thirteen out of 23 ADORA2A loci and 15/17 NT5E loci were significantly correlated with mRNA levels (p < 0.05). Inverse correlations were predominately found in promoter regions, while positive correlations were more profound at intragenic loci. ADORA2A hypermethylation was significantly associated with poor overall survival (OS, p ≤ 0.030), whereas NT5E hypomethylation was associated with decreased OS in HPV-positive tumors (p ≤ 0.024) and increased OS in HPV-negative HNSCC (p ≤ 0.029). Further, we found significant correlations between methylation and immune cell infiltrates. Conclusion: Our data might point towards a significant role of the A2aR/CD73 axis during cancer progression in HNSCC.

Prognostic value of aberrant promoter hypermethylation of tumor-related genes in early-stage head and neck cancer

Staging and pathological grading are useful, but imperfect predictors of recurrence in head and neck squamous cell carcinoma (HNSCC). Accordingly, molecular biomarkers that predict the risk of recurrence are necessary to improve clinical outcomes. The methylation statuses of the promoters of 11 tumor-related genes (p16, RASSF1A, E-cadherin, H-cadherin, MGMT, DAPK, DCC, COL1A2, TAC1, SST, and GALR1) were analyzed in 133 HNSCC cases using quantitative methylation-specific PCR. We detected frequent methylation of p16 (44%), RASSF1A (18%), E-cadherin (53%), H-cadherin (35%), MGMT (35%), DAPK (53%), DCC (42%), COL1A2 (44%), TAC1 (61%), SST (64%), and GALR1 (44%) in HNSCC. Disease-free survival was lower in patients with 6–11 methylated genes than in those with 0–5 methylated genes (log-rank test, P = 0.001). In a multivariate Cox proportional hazards analysis, the methylation of E-cadherin, COL1A2, TAC1, and GALR1 was associated with poor survival, with hazard ratios of 4.474 (95% CI, 1.241–16.124). In a joint analysis of these four genes, patients with 2–4 methylated genes had a significantly lower survival rate than those with 0–1 methylated genes in early-stage HNSCC. Importantly, the methylation of some genes was closely related to poor prognosis in early-stage HNSCC, providing strong evidence that these hypermethylated genes are valuable biomarkers for prognostic evaluation.

Radiation and chemotherapy with no excessive toxicity in a patient with human papillomavirus-related tonsillar cancer and porphyria cutanea tarda: Case report and literature review

BACKGROUND

Porphyria is a condition of cutaneous photosensitivity. It is unclear if radiotherapy (RT) is safe in patients with porphyria.

METHODS

We report a patient case with uncontrolled porphyria cutanea tarda treated with chemoradiation for p16-positive oropharyngeal cancer. Given the scarcity of data on this subject, we also conducted a literature review on the topic of radiation in patients with porphyria.

RESULTS

The patient in our study did not experience any unusual acute or late toxicity, despite receiving a high dose of cutaneous radiation. We also found the majority of the literature supports the safe use of therapeutic radiation in patients with porphyria.

CONCLUSION

In this patient, and in the majority of the literature, radiation seems safe in patients with porphyria; however, there are few reports on the subject in the literature, therefore, caution is warranted.

A 5‑year update of patients with HPV positive versus negative oropharyngeal cancer after radiochemotherapy in Austria

Background

After publishing promising results for the treatment of patients with human papilloma virus (HPV) positive oropharyngeal cancer with radiochemotherapy regarding 2‑year survival, we present an update of the disease-specific and disease-free survival after 5 years.

Patients and methods

A total of 29 patients of which 18 were HPV negative and 11 HPV positive with squamous cell carcinoma of the oropharynx received radiation therapy with or without chemotherapy (cisplatin) or immunotherapy (cetuximab) between 2007 and 2009. At time of the present analysis, six patients are still alive including four with HPV positive and two with HPV negative oropharyngeal carcinoma, while 15 out of 16 patients with HPV negative tumors died and 1 died of another cause with evidence of disease.

Results

Since the 2‑year disease-specific survival of patients with HPV positive cancer of the oropharynx was published with 100% versus 30.4% in HPV negative tumors, we now present the 5‑year disease-specific survival after treatment, which was 85.7% in HPV positive versus 11.1% in HPV negative patients.

Conclusion

We present the results of patients receiving radiochemo(immuno)therapy for oropharyngeal cancer regarding the HPV status, which is still promising.

Oncological and survival outcomes following transoral robotic surgery versus transoral laser microsurgery for the treatment of oropharyngeal squamous cell carcinoma: a systematic review protocol

OBJECTIVE/REVIEW QUESTIONS

The objective of this systematic review is to synthesize the best available evidence regarding the oncological and survival outcomes (as measured by disease control, disease-free survival, disease-specific survival and overall survival) of transoral robotic surgery (TORS) versus transoral laser microsurgery (TLM) in the treatment of oropharyngeal squamous cell carcinoma in adults (aged 18 years or older). Specifically the review questions are:1 Is there a difference in oncological outcomes between a traditional "Halstedian" en bloc tumor resection technique used in TORS versus a modern segmental tumor dissection technique used in TLM?2 Does one surgical approach confer better oncological outcomes with respect to a particular patient subgroup, such as patients with a positive human papilloma virus status or patient's with different tumor T-stages?

Transoral robotic surgery and oropharyngeal cancer: a literature review

The incidence of head and neck squamous cell carcinoma has risen steadily over the past decade due to the increase in cancers associated with the human papillomavirus (HPV). The prognosis for the treatment of this type of cancer with radiotherapy and chemoradiotherapy is good. However, because these treatments can have detrimental effects on organ function and quality of life, researchers are looking into transoral robotic surgery (TORS) as a possible alternate therapy. TORS might have a positive effect on postoperative function and quality of life for cancer survivors. The aim of this review is to report on the current situation regarding the treatment of oropharyngeal cancer with TORS, with a focus on the long-term oncologic and functional outcomes of this strategy. The articles cited in this review were selected from the PubMed and MEDLINE database. They contain study results pertaining to TORS implementation, complications, oncologic and functional outcomes, and the implications of HPV-associated cancer. We found that while TORS has some clear advantages and strengths and almost certainly a permanent place in future treatment, further research is necessary to correctly evaluate the role it will play in the complete management of oropharyngeal cancer.

[Is (chemo)radiotherapy really the future standard in the treatment of oropharyngeal carcinoma?]

Treatment of patients with oropharyngeal squamous cell carcinoma (OPSCC) requires interdisciplinary collaboration. Besides oncologic control, organ and function preservation are important priorities. One treatment option is primary concomitant chemoradiotherapy (CRT), particularly for locally advanced head and neck cancer. Another option is sequential CRT, where induction chemotherapy may be followed either by radiation alone or by CRT. An important aspect of these modalities is the development of functional sequelae with regards to swallowing as a direct consequence of radiogenic fibrosis, as well as tissue ctoxicity associated with cisplatin-based chemotherapy. Conventional open surgical approaches are being increasingly replaced by transoral surgical modalities with less treatment-related morbidity. As a further, equally important goal of appropriately indicated surgery, adjuvant (C)RT may be omitted or the dose significantly reduced. The advantages of primary surgery over primary CRT may be less obvious in cases still requiring adjuvant treatment, although not necessarily completely eliminated. For patients with human papillomavirus (HPV)-driven OPSCC, it is important to note that primary surgery may provide comparable or even increased survival benefit. To date, there is no evidence for a clear advantage of primary CRT over primary surgery in this group. In these cases, a de-escalated treatment package may be the preferred option. Here, the application of radioimmunotherapy as well as a reduced radiation dose may minimize long-term treatment-related morbidities.

Head and Neck Squamous Cell Carcinoma: Update on Epidemiology, Diagnosis, and Treatment

Squamous cell carcinoma arises from multiple anatomic subsites in the head and neck region. The risk factors for development of cancers of the oral cavity, oropharynx, hypopharynx, and larynx include tobacco exposure and alcohol dependence, and infection with oncogenic viruses is associated with cancers developing in the nasopharynx, palatine, and lingual tonsils of the oropharynx. The incidence of human papillomavirus-associated oropharyngeal cancer is increasing in developed countries, and by 2020, the annual incidence could surpass that of cervical cancer. The treatment for early-stage squamous cell cancers of the head and neck is generally single modality, either surgery or radiotherapy. The treatment for locally advanced head and neck cancers is multimodal, with either surgery followed by adjuvant radiation or chemoradiation as indicated by pathologic features or definitive chemoradiation. For recurrent disease that is not amenable to a salvage local or regional approach and for metastatic disease, chemotherapy with or without a biological agent is indicated. To date, molecular testing has not influenced treatment selection in head and neck cancer. This review will focus on the changing epidemiology, advances in diagnosis, and treatment options for squamous cell cancers of the head and neck, along with data on risk stratification specific to oropharyngeal cancer, and will highlight the direction of current trials.

Asian expert recommendation on management of skin and mucosal effects of radiation, with or without the addition of cetuximab or chemotherapy, in treatment of head and neck squamous cell carcinoma

With increasing numbers of patients with unresectable locoregionally advanced (LA) head and neck squamous cell carcinoma (HNSCC) receiving cetuximab/radiotherapy (RT), several guidelines on the early detection and management of skin-related toxicities have been developed. Considering the existing management guidelines for these treatment-induced conditions, clinical applicability and standardization of grading methods has remained a cause of concern globally, particularly in Asian countries. In this study, we attempted to collate the literature and clinical experience across Asian countries to compile a practical and implementable set of recommendations for Asian oncologists to manage skin- and mucosa-related toxicities arising from different types of radiation, with or without the addition of cetuximab or chemotherapy. In December 2013, an international panel of experts in the field of head and neck cancer management assembled for an Asia-Pacific head and neck cancer expert panel meeting in China. The compilation of discussion outcomes of this meeting and literature data ultimately led to the development of a set of recommendations for physicians with regards to the approach and management of dermatological conditions arising from RT, chemotherapy/RT and cetuximab/RT, and similarly for the approach and management of mucositis resulting from RT, with or without the addition of chemotherapy or cetuximab. These recommendations helped to adapt guidelines published in the literature or text books into bedside practice, and may also serve as a starting point for developing individual institutional side-effect management protocols with adequate training and education.

The rationale for HPV-related oropharyngeal cancer de-escalation treatment strategies

The treatment paradigms for head and neck squamous cell cancer (HNSCC) are changing due to the emergence of human papillomavirus-associated tumors (HPV-related), possessing distinct molecular profiles and responses to therapy. Retrospective studies have suggested that HPV-related HNSCCs are more frequently cured than those caused by tobacco. Current clinical trials focus on the reduction of treatment-related toxicity and the development of HPV-targeted therapies. New treatment strategies include: 1) dose reduction of radiotherapy, 2) the use of cetuximab instead of cisplatin for chemo-radiation 3) less invasive surgical options, i.e. trans-oral robotic surgery and trans-oral laser microlaryngoscopy, and 4) more specific treatment attempts, including immunotherapeutic strategies, thanks to increasing comprehension of the molecular background of HPV-related HNSCC. Whereas recently published data shed light on immune mechanisms, other studies have focused on specific vaccination against HPV-related HNSCC. A crucial problem is patient selection to the chosen bias. Truly HPV-related cancers (p16-positive and HPV DNA-positive) with biomarkers for good response to therapy could be included in randomized trials aiming for less severe and better tailored therapy.

Targeted Therapy in Oropharyngeal Squamous Cell Carcinoma: The Implications of HPV for Therapy

Oropharyngeal cancers caused by human papillomaviruses (HPV) have a different epidemiology, prognosis, genetic mutational landscape, response to treatment, and outcome when compared to HPV-negative cancers. In this review, a summary of our current understanding of HPV in head and neck cancer and the important advances that have shown HPV to be an etiological agent are discussed. HPV-positive and HPV-negative tumors are compared discussing clinicopathological factors, prognosis, outcome following treatment, and the molecular and genetic differences. Currently, the standard of care for oropharyngeal cancer is both surgery and post-operative radiotherapy with or without cisplatin or concurrent chemo-radiotherapy. The latter is used more often, especially in cancers of tonsil and base of tongue. However, there is increased interest in trying to de-intensify treatment and in the development of new treatments to target the underlying different molecular pathways of HPV-positive cancers. The current clinical trials involving surgery, chemotherapy, and radiation therapy are discussed. The new targeted treatments are also summarized. Although there is currently is no evidence from prospective studies to support a change in the treatment algorithm, the treatment options for patients with HPV-positive disease are likely to change in the future.

Evaluation of HPV Genotyping Assays for Archival Clinical Samples

Human papillomavirus (HPV) testing and genotyping of FFPE tissue samples is important in epidemiological investigations. Here, we compare four different HPV genotyping methods for use in FFPE clinical samples. Comparative testing was performed on 99 samples with a clinical suspicion of HPV. Specimens were analyzed with Anyplex II HPV28 detecting 28 genotypes using real-time PCR and melting curve analysis, CLART HPV2 detecting 35 genotypes using PCR and microarray detection, and MGP5+/6+ consensus primer system together with pyrosequencing. Results were compared to a real-time PCR reference protocol detecting 14 genotypes. In total, 68% of the samples were positive for an HPV genotype using the reference protocol and MGP5+/6+ primer system. Anyplex II HPV28 analysis and CLART HPV2 had 82% and 72% positive samples, respectively. All four methods showed good agreement when comparing the 14 genotypes included in the reference protocol. When evaluating all genotypes, the Anyplex II HPV28 assay and the CLART assay changed the status of the sample (individually or together) from negative with respect to the reference protocol to positive for either a Group 1 (n = 4) or Group 2 (n = 6) genotype. We conclude from this study that for an extended genotyping approach with a high sensitivity for FFPE specimens, both the Anyplex II HPV28 and CLART HPV2 assays are suitable alternatives despite minor intra-assay differences.

Radioresistance in head and neck squamous cell carcinoma: Biological bases and therapeutic implications

Head and neck squamous cell carcinoma (HNSCC) is strongly associated with alcohol and tobacco consumption. Lately, the incidence of human papillomavirus (HPV)-related tumors has shown a significant increase, and HPV-related tumors show distinctive features if compared with the HPV-negative counterpart. Locally advanced HNSCC can be treated with concomitant chemoradiotherapy, but early recurrences sometimes occur. Relapses are often related to an intrinsic radioresistance of the tumors. Alterations in intracellular pathways, primarily involved in cell proliferation, apoptosis, and DNA repair, can lead to radioresistance. Preclinical and clinical evidence highlighted that 3 main pathways, including the epidermal growth factor receptor (EGFR), the phosphotidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR), and the p53 signaling cascades, play a crucial role in radioresistance development. A future approach may consist in the association of radiotherapy (RT) and selective inhibition of the key pathways involved in radioresistance. Phase I, II, and III clinical trials are currently testing these novel treatment strategies.

Translational genomics and head and neck cancer: toward precision medicine

Head and neck squamous cell carcinoma (HNSCC) comprise a wide spectrum of neoplasms with different tumor biologies, prognosis and response to therapies. Current tumor classification and traditional diagnostic methods (e.g. clinical assessment, histopathology) are limited in their capacity to determine prognosis and clinical decision-making. Despite recent improvements in treatment, the outcome for patients with HNSCC remains poor. Similar to most tumors, several patient-related factors, (e.g. genetics and environment) and disease-related factors (e.g. tumor location, TMN staging) play a significant role on survival. Thus, the problem in defining the prognosis is that the clinical course and response to treatment differ considerably among patients. Such interindividual variability is related to the heterogeneity of the tumor, genetic and epigenetic variations, thus reflecting the interaction of multiple biological components that result in a unique phenotype. Integrative genomics are developed to identify the molecular pathways leading to cancer at the individual level and find novel prognostic markers for HNSCC, hence tailoring a treatment accordingly. Such genetic-based personalized diagnosis allows tumor stratification and implementation of targeted therapy. Modern medicine includes new drugs that disrupt the implicated molecules and their signaling pathways. Here, we summarize the current state of knowledge that elucidates the translation of genetic data into clinical benefit.

The current and future impact of human papillomavirus on treatment of squamous cell carcinoma of the head and neck

BACKGROUND

Squamous cell carcinoma of the head and neck (SCCHN) was traditionally associated with smoking and alcohol use; however, human papillomavirus (HPV) infection has recently been implicated as a novel risk factor for oropharyngeal tumors. Furthermore, HPV-associated oropharyngeal carcinoma (OPC) appears to be a distinct entity with different epidemiology, biology, and clinical outcomes.

METHODS

Here, we comprehensively review the existing data regarding HPV status and prognostic or predictive outcomes in both the locoregionally advanced (LA) and recurrent/metastatic (RM) disease setting and discuss ongoing trials that may eventually impact the treatment of patients with HPV-positive (HPV+) SCCHN.

RESULTS

A body of retrospective and prospective data established an association between HPV+ OPC and better survival, particularly for LA disease. Current data on RM disease are limited, but they also suggest prognostic significance for HPV.

CONCLUSIONS

Better outcomes in HPV+ LA disease may allow for less aggressive treatment in the future, and several trials are evaluating deintensified regimens in patients with HPV+, LA OPC; it should be emphasized that deintensification strategies are appropriate only in a clinical research setting and only for selected subgroups of HPV+ patients. In addition, HPV-targeted strategies, such as vaccines, are currently undergoing clinical evaluation. On the other hand, the prognostic impact of HPV in RM disease requires further validation before any modifications in treatment can be made. Likewise, the predictive significance of HPV status in both disease settings remains to be defined.

CLINICAL TRIAL NUMBERS

NCT00226239, NCT00301028, NCT00387127, NCT00410826, NCT00503997, NCT00514943, NCT00544414, NCT00768664, NCT00939627, NCT01084083, NCT01302834, NCT01687413, NCT01706939.

Transoral Robotic Surgery in the HPV Era

The incidence of oropharyngeal squamous cell carcinoma (OPSCC) has markedly increased over the last three decades mostly due to human papillomavirus (HPV)-related infections. Cancers resulting from HPV infection bear a better prognosis than those that are smoking-related. Because HPV-positive patients are often younger, with lower rates of co-morbid illness and longer overall life expectancies, long-term sequelae of therapy have become an important issue. Treatment of oropharyngeal cancers has typically involved the use of radiation and chemotherapy to avoid the morbidity of open surgery which included mandibulotomy and composite resection. Transoral robotic surgery (TORS) is an emerging treatment option for this disease, avoiding the morbidity of open approaches while providing excellent oncologic and functional outcomes. With overall survival rate at 2 years exceeding 80%, and local failure rate of less than 3%, patients receiving TORS report relatively good health-related quality of life (QOL) scores. The aim of the current review is to provide a summary of the current literature with regard to the oncologic and functional outcomes following treatment of OPSCC with TORS.

Dose escalation to high-risk sub-volumes based on non-invasive imaging of hypoxia and glycolytic activity in canine solid tumors: a feasibility study

INTRODUCTION

Glycolytic activity and hypoxia are associated with poor prognosis and radiation resistance. Including both the tumor uptake of 2-deoxy-2-[18 F]-fluorodeoxyglucose (FDG) and the proposed hypoxia tracer copper(II)diacetyl-bis(N4)-methylsemithio-carbazone (Cu-ATSM) in targeted therapy planning may therefore lead to improved tumor control. In this study we analyzed the overlap between sub-volumes of FDG and hypoxia assessed by the uptake of 64Cu-ATSM in canine solid tumors, and evaluated the possibilities for dose redistribution within the gross tumor volume (GTV).

MATERIALS AND METHODS

Positron emission tomography/computed tomography (PET/CT) scans of five spontaneous canine solid tumors were included. FDG-PET/CT was obtained at day 1, 64Cu-ATSM at day 2 and 3 (3 and 24 h pi.). GTV was delineated and CT images were co-registered. Sub-volumes for 3 h and 24 h 64Cu-ATSM (Cu3 and Cu24) were defined by a threshold based method. FDG sub-volumes were delineated at 40% (FDG40) and 50% (FDG50) of SUVmax. The size of sub-volumes, intersection and biological target volume (BTV) were measured in a treatment planning software. By varying the average dose prescription to the tumor from 66 to 85 Gy, the possible dose boost (DB) was calculated for the three scenarios that the optimal target for the boost was one, the union or the intersection of the FDG and 64Cu-ATSM sub-volumes.

RESULTS

The potential boost volumes represented a fairly large fraction of the total GTV: Cu3 49.8% (26.8-72.5%), Cu24 28.1% (2.4-54.3%), FDG40 45.2% (10.1-75.2%), and FDG50 32.5% (2.6-68.1%). A BTV including the union (∪) of Cu3 and FDG would involve boosting to a larger fraction of the GTV, in the case of Cu3∪FDG40 63.5% (51.8-83.8) and Cu3∪FDG50 48.1% (43.7-80.8). The union allowed only a very limited DB whereas the intersection allowed a substantial dose escalation.

CONCLUSIONS

FDG and 64Cu-ATSM sub-volumes were only partly overlapping, suggesting that the tracers offer complementing information on tumor physiology. Targeting the combined PET positive volume (BTV) for dose escalation within the GTV results in a limited DB. This suggests a more refined dose redistribution based on a weighted combination of the PET tracers in order to obtain an improved tumor control.