Human papillomavirus genotype distribution in head and neck cancer: Informing developing strategies for cancer prevention, diagnosis, treatment and surveillance

Lacrimal sac ciliated HPV16 positive, adenosquamous carcinoma-A case report of a unique histological variant at this site and a review of the literature

A 47-year-old female developed a reddish swelling of the right medial canthus over 3 months. On examination, a red, firm mass, involving the right medial canthal and extending into the inferior fornix was present and the globe was displaced upwards and inwards. A staging MRI scan confirmed a lacrimal sac lesion with anterior orbit extension. After an equivocal biopsy, the patient underwent debulking surgery. Histology showed a lacrimal sac invasive adenosquamous carcinoma, comprising poorly differentiated squamous carcinoma and invasive adenocarcinoma areas arranged in a tubulo-glandular pattern. The adenocarcinoma harboured numerous cilia. p16 showed block positivity of both components and micro-dissected tissue from both areas showed the presence of HPV16 DNA by PCR. This is the first description of ciliated adenosquamous carcinoma of the lacrimal sac and this finding is placed into the context of what is known about ciliated head and neck adenosquamous carcinomas and the role of high-risk HPV.

Reappraisal of p16 for Determining HPV Status of Head and Neck Carcinomas Arising in HPV Hotspots

In an era of head and neck oncology where HPV status will soon dictate patient management, reliable HPV detection is critical. P16 immunohistochemistry (IHC) is currently recommended as the test of choice for oropharyngeal squamous cell carcinomas (OPSCCs). The purpose of this study was to determine the performance characteristics of p16 IHC based on a large clinical experience of squamous cell carcinomas (SCC) arising from HPV hot-spot regions of the head and neck. Consecutive OPSCCs, sinonasal SCCs, and metastatic SCCs of unknown primary sites were evaluated for the presence of HPV by p16 IHC and PCR-based HPV DNA testing as part of clinical care. For discrepant cases, high-risk HPV E6/E7 mRNA in situ hybridization (ISH) and, when possible, matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MassArray) genotyping were performed. 746 cancers underwent HPV testing by p16 IHC and DNA PCR genotyping. There was a 95.6% concordance between the 2 assays. Of the 33 discrepant cases, 32 cases (4.3%) were p16 positive but HPV DNA negative. In these cases, 68% were positive for mRNA ISH, invariably related to a non-16 HPV genotype. P16 IHC had an overall accuracy of 98.8%, a sensitivity of 99.8%, and a specificity of 92.1%. P16 IHC is a sensitive and specific assay for determining HPV status. HPV DNA PCR appears vulnerable to HPV genotype diversity and is prone to missing rare non-16 genotypes. HPV mRNA ISH is a practical and reliable direct measure of HPV that may help eliminate the small number of false-positive p16 cases and avoid potential patient harm related to erroneous HPV classification.

HPV-associated oropharyngeal cancer: in search of surrogate biomarkers for early lesions

The incidence of oropharyngeal cancer (OPSCC) has escalated in the past few decades; this has largely been triggered by high-risk human papillomavirus (HPV). Early cancer screening is needed for timely clinical intervention and may reduce mortality and morbidity, but the lack of knowledge about premalignant lesions for OPSCC poses a significant challenge to early detection. Biomarkers that identify individuals at high risk for OPSCC may act as surrogate markers for precancer but these are limited as only a few studies decipher the multistep progression from HPV infection to OPSCC development. Here, we summarize the current literature describing the multistep progression from oral HPV infection, persistence, and tumor development in the oropharynx. We also examine key challenges that hinder the identification of premalignant lesions in the oropharynx and discuss potential biomarkers for oropharyngeal precancer. Finally, we evaluate novel strategies to improve investigations of the biological process that drives oral HPV persistence and OPSCC, highlighting new developments in the establishment of a genetic progression model for HPV + OPSCC and in vivo models that mimic HPV + OPSCC pathogenesis.

Molecular pathology in diagnosis and prognostication of head and neck tumors

Classification of head and neck tumors has evolved in recent decades including a widespread application of molecular testing in tumors of the salivary glands, sinonasal tract, oropharynx, nasopharynx, and soft tissue. Availability of new molecular techniques allowed for the definition of multiple novel tumor types unique to head and neck sites. Moreover, the expanding spectrum of immunohistochemical markers facilitates a rapid identification of diagnostic molecular abnormalities. As such, it is currently possible for head and neck pathologists to benefit from a molecularly defined classifications, while making diagnoses that are still based largely on histopathology and immunohistochemistry. This review highlights some principal molecular alterations in head and neck neoplasms presently available to assist pathologists in the practice of diagnosis, prognostication and prediction of response to treatment.

Practical Application of Circulating Tumor-Related DNA of Human Papillomavirus in Liquid Biopsy to Evaluate the Molecular Response in Patients with Oropharyngeal Cancer

Recent findings have shown that human papillomavirus (HPV) DNA is present in the blood as a tumor-specific biomarker (circulating tumor-related HPV; ctHPV) in patients with HPV-related oropharyngeal cancer (HPV-related OPC). The molecular response (MR) in patients with HPV-related OPC can be defined as the change in the number of ctHPV copies in relation to its initial quantity. The optimal model for assessing the MR using a liquid biopsy (LB) should be based on the E6/E7 sequences of the viral genome. MR assessment can help to evaluate the intensity of ongoing treatments in relation to the tumor response. The evaluation of the residual disease at the end of therapy may also be performed by MR assessment. If a partial MR (pMR) is found, caution is indicated and a subsequent LB should be considered, due to the likelihood of disease progression. Complete radiological and clinical responses together with a complete MR (cMR) convincingly indicate a low risk of treatment failure. Moreover, molecular recurrence (Mrec) during a follow-up, confirmed in two consecutive assays, even despite the lack of any other clinical or radiological symptoms of progression, indicates patients at high risk of disease recurrence. In conclusion, MR by ctHPV assessment may hasten the early detection of disease progression, at any stage of the management of the patient with HPV-related OPC.

Oropharyngeal Carcinoma with a Special Focus on HPV-Related Squamous Cell Carcinoma

Human papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV-OPSCC) has one of the most rapidly increasing incidences of any cancer in high-income countries. The most recent (8th) edition of the Union for International Cancer Control/American Joint Committee on Cancer staging system separates HPV-OPSCC from its HPV-negative counterpart to account for the improved prognosis seen in the former. Indeed, owing to its improved prognosis and greater prevalence in younger individuals, numerous ongoing trials are examining the potential for treatment deintensification as a means to improve quality of life while maintaining acceptable survival outcomes. Owing to the distinct biology of HPV-OPSCCs, targeted therapies and immunotherapies have become an area of particular interest. Importantly, OPSCC is often detected at an advanced stage, highlighting the need for diagnostic biomarkers to aid in earlier detection. In this review, we highlight important advances in the epidemiology, pathology, diagnosis, and clinical management of HPV-OPSCC and underscore the need for a progressive understanding of the molecular basis of this disease toward early detection and precision care.

Cobas HPV Genotyping of FNA Sample Supernatant and Frozen Section Scrapings of Suspected Head and Neck Cancer

The human papillomavirus (HPV) status of squamous cell carcinomas (SCCs) of the head and neck is relevant for therapy planning, staging, and follow-up. Immunohistochemistry (IHC) for p16 is a surrogate marker of HPV status in oropharyngeal SCC, but not at other head and neck sites. We tested if the cobas HPV test was feasible and superior to p16-IHC on fine-needle aspiration (FNA) supernatants and frozen section (FS) scrapings of suspected SCC. A 500 μL aliquots of postcentrifugation supernatant CytoRich Red media of FNA cellblock specimens and scrapings of FS suspended in SurePath media vials were tested with the cobas HPV test and compared with p16-IHC and/or HPV in situ hybridization (ISH) performed on cellblock and/or resections. Twenty-nine (n=29) FNAs were tested for a cobas HPV test, p16, and/or HPV-ISH. The mean collection to testing time was 6.3 days (range: 0 to 24 d). Cobas yielded valid results in all cases; p16-IHC could not be interpreted in 4 (13%) cellblocks; correlation was performed on subsequent resections. Cohen κ correlation for cobas versus p16-IHC/HPV-ISH on FNA samples was 0.9, perfect agreement, sensitivity 100%, specificity 92.3%, positive predictive value 94.1%, negative predictive value 100%. Thirty-four (n=34) scrapings from FS were tested for cobas, p16, and/or HPV-ISH. The mean collection to testing time was 10.4 days (range: 1 to 28 d). Cohen κ correlation for cobas versus p16-IHC/HPV-ISH on FS scrapings was 1, perfect agreement. Sensitivity, specificity, positive predictive value, and negative predictive value was 100%. Cobas genotype was HPV-16 in 87%, HPV-18 in 3%, and HPV-other in 10%. Cobas HPV test in FNA supernatant and FS scrapings outperformed or was equivalent to p16-IHC and provided genotyping information.

A clinician’s dilemma: what should be communicated to women with oncogenic genital HPV and their partners regarding the risk of oral viral transmission?

Head and neck cancer, the sixth most common cancer worldwide, account for about 1 out of 20 malignant tumors. In recent years a reduction in the incidence of cervical cancer, but a concomitant major increase in the incidence of HPV-mediated oropharyngeal cancer caused by orogenital HPV transmission has been observed. Consequently, in wealthy countries oropharyngeal squamous-cell carcinomas (OPSCC) is now the most frequent HPV-related cancer, having overtaken cervical cancer. Without effective medical interventions, this incidence trend could continue for decades. As no specific precursor lesion has been consistently identified in the oral cavity and oropharynx, HPV vaccination is the logical intervention to successfully counteract also the rising incidence of OPSCCs. However, HPV vaccine uptake remains suboptimal, particularly in males, the population at higher risk of OPSCC. Alternative primary prevention measures, such as modifications in sexual behaviors, could be implemented based on knowledge of individual genital HPV status. Until recently, this information was not available at a population level, but the current gradual shift from cytology (Pap test) to primary HPV testing for cervical cancer screening is revealing the presence of oncogenic viral genotypes in millions of women. In the past, health authorities and professional organizations have not consistently recommended modifications in sexual behaviors to be adopted when a persistent high-risk HPV cervicovaginal infection was identified. However, given the above changing epidemiologic scenario and the recent availability of an immense amount of novel information on genital HPV infection, it is unclear whether patient counseling should change. The right of future partners to be informed of the risk could also be considered. However, any modification of the provided counseling should be based also on the actual likelihood of a beneficial effect on the incidence of HPV-associated oropharyngeal cancers. The risk is on one side to induce unjustified anxiety and provide ineffective instructions, on the other side to miss the opportunity to limit the spread of oral HPV infections. Thus, major health authorities and international gynecologic scientific societies should issue or update specific recommendations, also with the aim of preventing inconsistent health care professionals’ behaviors.

Concordance of p16INK4a and E6*I mRNA among HPV-DNA-Positive Oropharyngeal, Laryngeal, and Oral Cavity Carcinomas from the ICO International Study

Background: Tests or test algorithms for diagnosing HPV-driven oral cavity and laryngeal head and neck carcinomas (HNC) have not been yet validated, and the differences among oral cavity and laryngeal sites have not been comprehensively evaluated. We aimed to assess the utility of a diagnostic algorithm for the detection of HPV-driven oral cavity (OCC), oropharyngeal (OPC) and laryngeal (LC) carcinomas using HPV-DNA testing followed by p16INK4a immunohistochemistry, taking E6*I mRNA detection as the reference standard. Methods: Formalin-fixed paraffin-embedded OCC, OPC, and LC carcinomas were collected from pathology archives in 29 countries. All samples were subjected to histopathological evaluation, DNA quality control, and HPV-DNA detection. All HPV-DNA-positive samples (including 78 OCC, 257 OPC, and 51 LC out of 3680 HNC with valid HPV-DNA results) were also tested for p16INK4a immunohistochemistry and E6*I mRNA. Three different cutoffs of nuclear and cytoplasmic staining were evaluated for p16INK4a: (a) >25%, (b) >50%, and (c) ≥70%. The concordance of p16INK4a and E6*I mRNA among HPV-DNA-positive OCC, OPC, and LC cases was assessed. Results: A total of 78 OCC, 257 OPC, and 51 LC were HPV-DNA-positive and further tested for p16INK4a and E6*I mRNA. The percentage of concordance between p16INK4a (cutoff ≥ 70%) and E6*I mRNA among HPV-DNA-positive OCC, OPC, and LC cases was 79.5% (95% CI 69.9−89.1%), 82.1% (95% CI 77.2−87.0%), and 56.9% (95% CI 42.3−71.4%), respectively. A p16INK4a cutoff of >50% improved the concordance although the improvement was not statistically significant. For most anatomical locations and p16INK4a cutoffs, the percentage of discordant cases was higher for HPV16- than HPV-non16-positive cases. Conclusions: The diagnostic algorithm of HPV-DNA testing followed by p16INK4a immunohistochemistry might be helpful in the diagnosis of HPV-driven OCC and OPC, but not LC. A different p16INK4a expression pattern was observed in those cases HPV-DNA-positive for types other than HPV16, as compared to HPV16-positive cases. Our study provides new insights into the use HPV-DNA, p16INK4a, and HPV-E6*I mRNA for diagnosing an HPV-driven HNC, including the optimal HPV test or p16INK4a cutoffs to be used. More studies are warranted to clarify the role of p16INK4a and HPV status in both OPC and non-OPC HNC.

Effect of experimental and commercial artificial saliva formulations on the activity and viability of microcosm biofilm and on enamel demineralization for irradiated patients with head and neck cancer (HNC)

The effect of different artificial saliva formulations on biofilm activity and viability, and on enamel demineralization for head and neck cancer (HNC) patients was evaluated. Irradiated enamel samples were treated (1 min) with BioXtra® or with experimental formulations containing carboxymethylcellulose plus inorganic constituents alone (AS) or containing 0.1 mg mL^-1 CaneCPI-5 (AS + Cane), 1.0 mg mL^-1 hemoglobin (AS + Hb) or combination of both (AS + Cane + Hb). Phosphate-buffered-saline and chlorhexidine (0.12%) were negative and positive control, respectively. Biofilm was produced from the saliva of five male HNC patients, under 0.2% sucrose exposure for 5 days, and daily treated with the formulations (1 min). No significant effects were observed for the different experimental treatments. BioXtra^® significantly reduced lactobacilli, demonstrating antibacterial potential for this group. Chlorhexidine was an effective treatment to significantly reduce all parameters, being an important antimicrobial and anticaries agent. Future in vitro studies must be performed using a new approach for the design of the experimental formulations.

The Prevalence of High- and Low-Risk Types of HPV in Patients with Squamous Cell Carcinoma of the Head and Neck, Patients with Chronic Tonsillitis, and Healthy Individuals Living in Poland

Human papillomavirus (HPV) is a virus with the potential to infect human epithelial cells and an etiological agent of many types of cancer, including head and neck cancer. The aim of the study was to determine the prevalence of HPV infection in patients with head and neck squamous cell carcinoma (HNSCC), patients with chronic tonsillitis, and healthy individuals, and to establish high- and low-risk HPV genotypes in these groups. The objectives also comprised the delineation of the relationship between the infection with high- or low-risk HPV subtypes and clinicopathological and demographic characteristics of the study groups. This study was composed of 76 patients diagnosed with HNSCC, 71 patients with chronic tonsillitis, and 168 cases without either of these conditions (the control group). HPV detection and identification of subtypes were performed on isolated DNA using a test which allowed detection of 33 common high-risk and low-risk HPV subtypes. The prevalence of HPV infection was 42.1%, 25.4%, and 37.5% in HNSCC, chronic tonsillitis, and control groups, respectively. HPV 16 was the most prevalent genotype in all groups and the non-oncogenic HPV 43/44 was frequent in HNSCC patients. This analysis provides insight into the prevalence of oral oncogenic and non-oncogenic HPVs in patients with head and neck cancer, patients with chronic tonsillitis and healthy individuals, and leads to the conclusion that further investigations are warranted to examine a larger cohort of patients focusing on high- and low-risk HPV genotypes. Efforts should be focused on screening and prevention strategies, and therefore, it is important to introduce tools for effective detection of HPV genotypes. Furthermore, given the role of vaccines against oral HPV infection, our observations lead to the suggestion that HPV vaccination should be of considerable importance in public health strategies.

Human papilloma virus circulating tumor DNA assay predicts treatment response in recurrent/metastatic head and neck squamous cell carcinoma

Despite the rising incidence of human papillomavirus related (HPV+) oropharyngeal squamous cell carcinoma (OPSCC), treatment of metastatic disease remains palliative. Even with new treatments such as immunotherapy, response rates are low and can be delayed, while even mild tumor progression in the face of an ineffective therapy can lead to rapid death. Real-time biomarkers of response to therapy could improve outcomes by guiding early change of therapy in the metastatic setting. Herein, we developed and analytically validated a new droplet digital PCR (ddPCR)-based assay for HPV16 circulating tumor DNA (ctDNA) and evaluated plasma HPV16 ctDNA for predicting treatment response in metastatic HPV+ OPSCC. We found that longitudinal changes HPV16 ctDNA correlate with treatment response and that ctDNA responses are observed earlier than conventional imaging (average 70 days, range: 35-166). With additional validation in multi-site studies, this assay may enable early identification of treatment failure, allowing patients to be directed promptly toward clinical trials or alternative therapies.