Brush-based cytology screening in the tonsils and cervix: there is a difference!

A brief review of cytology in dentistry

Oral cytology is a non-invasive adjunctive diagnostic tool with a number of potential applications in the practice of dentistry. This brief review begins with a history of cytology in medicine and how cytology was initially applied in oral medicine. A description of the different technical aspects of oral cytology is provided, including the collection and processing of oral cytological samples, and the microscopic interpretation and reporting, along with their advantages and limitations. Applications for oral cytology are listed with a focus on the triage of patients presenting with oral potentially malignant disorders and oral mucosal infections. Furthermore, the utility of oral cytology roles across both expert (for example, secondary oral medicine or tertiary head and neck oncology services) and non-expert (for example, primary care general dental practice) clinical settings is explored. A detailed section covers the evidence-base for oral cytology as a diagnostic adjunctive technique in both the early detection and monitoring of patients with oral cancer and oral epithelial dysplasia. The review concludes with an exploration of future directions, including the integration of artificial intelligence for automated analysis and point of care 'smart diagnostics', thereby offering some insight into future opportunities for a wider application of oral cytology in dentistry.

Is 2045 the best we can do? Mitigating the HPV-related oropharyngeal cancer epidemic

INTRODUCTION

Oropharyngeal cancer (OPC) will be among the most common cancers in men by 2045 due to a rapid rise in human papillomavirus (HPV)-related OPC. Those who survive their cancer often suffer life-long treatment effects and early death. HPV vaccination could prevent virtually all HPV-related cancers but is not an effective preventive strategy for those already exposed. Without a dramatic increase in vaccine uptake in the U.S., HPV vaccination will have a negligible effect on OPC incidence through 2045 and no substantial impact until 2060. Additionally, targeted screening for earlier diagnosis may soon be feasible for those inadequately protected by vaccination.

AREAS COVERED

PubMed search for English-language articles related to incidence, screening, and prevention of HPV-related malignancies, focused on OPC in the U.S.

EXPERT OPINION

HPV-related OPC incidence will continue to increase for the foreseeable future with prophylactic vaccination offering no substantial public health impact for decades. Consequently, we must rapidly increase vaccination rates and develop screening methods to identify high-risk individuals. Such individuals would be eligible for potential preventive treatments and screening to diagnose early-stage HPV-related OPC allowing less morbid treatments. These methods will bridge the population into an era of decreasing incidence after vaccination takes effect.

Accuracy of liquid-based brush cytology and HPV detection for the diagnosis and management of patients with oropharyngeal and oral cancer

Objectives

This study aims to evaluate the usefulness of liquid-based brush cytology for malignancy diagnosis and HPV detection in patients with suspected oropharyngeal and oral carcinomas, as well as for the diagnosis of tumoral persistence after treatment.

Material and methods

Seventy-five patients with suspicion of squamous cell carcinoma of the oropharynx or oral cavity were included. Two different study groups were analyzed according to the date of the sample collection: (1) during the first endoscopy exploration and (2) in the first control endoscopy after treatment for squamous cell carcinoma. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for malignancy diagnosis as well as for HPV-DNA detection on brush cytologies were assessed.

Results

Before treatment, the brush cytology showed a sensitivity of 88%, specificity of 100%, and accuracy of 88%. After treatment, it showed a sensitivity of 71%, specificity of 77%, and accuracy of 75%. HPV-DNA detection in cytology samples showed a sensitivity of 85%, specificity of 100%, and accuracy of 91% before treatment and an accuracy of 100% after treatment.

Conclusions

Liquid-based brush cytology showed good accuracy for diagnosis of oropharyngeal and oral squamous cell carcinoma before treatment, but its value decreases after treatment. Nevertheless, it is useful for HPV-DNA detection, as well as to monitor the patients after treatment.

Clinical relevance

Brush cytology samples are reliable for the detection of HPV-DNA before and after treatment and may be a useful method to incorporate in the HPV testing guidelines.

Screening for HPV-related oropharyngeal, anal, and penile cancers in middle-aged men: Initial report from the HOUSTON clinical trial

BACKGROUND

The Human papillomavirus (HPV)-related Oropharyngeal and Uncommon Cancers Screening Trial of Men (HOUSTON) was designed to determine the prevalence of IgG antibodies to HPV type 16 E proteins (HPV16EAbs), to screen for persistence of HPV and/or detect HPV-related premalignancies and cancers, and to assess acceptance of screening among middle-aged men.

METHODS

HOUSTON consists of a cross-sectional study and a longitudinal cohort study of men aged 50-64 years. Serologic HPV16EAb status and oral rinse HPV16 status were determined. All HPV16EAb-positive (HPV16EAb+) men and a matched cohort of HPV16EAb-negative (HPV16EAb-) men as well as all oral rinse HPV16-positive (HPV16+) men were included in the longitudinal study (blinded to their results) and underwent oropharyngeal screening every 6 months as well as one-time anal and penile screening.

RESULTS

Of 553 men enrolled in the cross-sectional study, six (1.1%) were HPV16EAb+ (two were also oral rinse HPV16+), and 41 (7.4%) were HPV16EAb- but oral rinse HPV16+. These 47 men, along with five matched controls, were invited to participate in the longitudinal study, and 42 (81%) agreed and completed baseline in-person screening, with 93% and 90% completeing 6-month and 12-month follow-up visits. One HPV16EAb+ (also oral rinse HPV16+) man, who declined participation in the longitudinal study, presented 4 months after enrollment with an early-stage HPV16-related pharyngeal cancer. Additionally, one HPV16EAb+ (oral rinse HPV16-) man and two oral rinse HPV16+ (HPV16EAb-) men were diagnosed with oncogenic HPV-associated anal dysplasia.

CONCLUSIONS

This biomarker panel deserves further prospective study to explore potential utility for HPV-related cancer screening among men.

Considerations in Human Papillomavirus-Associated Oropharyngeal Cancer Screening: A Review

Importance

The incidence of human papillomavirus (HPV)-positive oropharyngeal cancer (OPC) is anticipated to rise over the next few decades until the effects of prophylactic vaccination are realized, which highlights the potential importance of secondary prevention. The objective of this review is to evaluate the evidence associated with screening for HPV-positive OPC.

Observations

Evaluation of a potential clinical preventive screening service requires characterization of the disease burden, the at-risk target screening population, screening tests, treatment, and screening benefits and harms. The lifetime risk of OPC is 0.7% for men and 0.2% for women and is expected to increase. The disease burden of HPV-positive OPC is substantial; most patients undergo morbid multimodality treatment and incur high costs in the process. Middle-aged and older adult men with elevated number of lifetime vaginal or oral sex partners are at highest risk. Patients may benefit from early detection of the disease-the 4-year overall survival of patients with stage I HPV-positive OPC is 87%, a considerable portion of whom are eligible for less morbid single-modality therapy. However, available screening tests are insufficiently sensitive and specific considering the current HPV-positive OPC incidence rates in the most at-risk patients. Further, the benefits and harms of screening for HPV-positive OPC are unknown.

Conclusions and Relevance

The current and projected future population-level burden of HPV-positive OPC supports further exploration of secondary preventive interventions. However, screening for HPV-positive OPC is not currently justified. Advances in biomarker discovery and improved characterization of (1) a highly at-risk, target screening population and (2) the benefits and harms of screening will be necessary. Large-scale clinical trials and rigorous evaluation of how to best implement this service into clinical practice will also be needed.

Human papillomavirus genome variants and head and neck cancers: a perspective

Human papillomaviruses (HPV) cause infections that are responsible for diverse clinical manifestations from benign conditions to invasive cancer. As different HPV types are associated with variable pathogenic potential, minor genetic variations within a given high-risk HPV type might also be associated with distinct oncogenic capacities, through variable ability of persistence or risk of progression to precancer/cancer. Most recent HPV variant studies in the cervix using latest sequencing technology confirmed that minor changes in the HPV genome can have a major influence on carcinogenesis and have revealed key data that help better understand the carcinogenicity of HPV at a molecular level. Here we review the limited number of studies on HPV genome variants in head and neck cancers (HNC) and discuss their implications for cancer research in the light of accumulated knowledge for the cervix. Challenges in transposing HPV variant studies from the lower anogenital to the upper aerodigestive tract are also discussed, highlighting the main gaps of knowledge in the field of HPV-induced HNC. Specifically in the head and neck region, the lack of characterisation of precancerous lesions and the difficulty in sampling normal tissue will challenge the development of accurate studies. Although there is so far no indication that HPV variant research in HNC could directly translate into clinical application, such research is expected to be useful to disentangle unanswered questions in the pathogenesis of HNC. Yet, history of HPV variant research suggests that, to be successful, studies will require large international collaborative efforts.

Screening for Cancer in Persons Living with HIV Infection

Survival with human immunodeficiency virus (HIV) infection has greatly improved due to effective antiretroviral therapy (ART). As infectious complications have declined, malignancy now accounts for over one-third of deaths among people living with HIV (PLWH). Based on practices in the general population, cancer screening of PLWH can decrease both morbidity and mortality. In this article, we review and consider directed approaches for colorectal, breast, cervical and lung cancer screening. Furthermore, routine physical examinations may detect lymphomas and skin, anal and oral cancers. Comprehensive cancer prevention in PLWH should also include ART adherence, vaccination against oncogenic viruses, treatment of hepatitis viruses and smoking cessation. Cancer screening for PLWH warrants further research on safety and efficacy as well as targeted efforts to increase adherence.

Human papillomavirus and head and neck carcinomas: focus on evidence in the babel of published data

Human papillomavirus (HPV)-associated squamous cell carcinoma of the oropharynx is a well-defined entity mostly affecting young to middle-aged male non-smokers. It is generally associated with a favourable outcome, and for this reason a less intensive therapeutic approach has been proposed for this subset of patients. The incidence of HPV-associated oropharyngeal cancers is rapidly increasing in most Western countries, but detailed epidemiological data are not available for the Italian population. Furthermore, among other head and neck regions, a smaller proportion of oral high-grade dysplasia and cancers seems to depend on HPV infection, whereas its role in laryngeal cancer is recognised as less relevant. HPV-dependent neoplastic transformation depends on the expression of viral oncogenes in the infected host cell that can only be directly documented through viral oncogene mRNA identification. The consensus on how to classify these patients from clinical and laboratory diagnostic points of view is still limited, with different approaches based on one or more diagnostic techniques including p16 immunostaining, in situ hybridisation and polymerase chain reation (PCR) amplification of viral DNA. The possibility of early diagnosis relying on the identification of HPV infection in oral and oropharyngeal exfoliated cells has so far provided unsatisfactory results, although viral persistence after treatment has been associated with risk of recurrence. Presently, sufficient data are not available to document the natural history and progression from tonsillar HPV infection to oropharyngeal cancer development, and to clearly define the modality of transmission and risk exposure, among which sexual behaviours appear to play a relevant role. The diffusion of HPV vaccination and its administration to both genders will undoubtedly dramatically modify the epidemiology of HPV-related head and neck cancers in the coming years.

Deep brush-based cytology in tonsils resected for benign diseases

A fraction of oropharyngeal cancer (OPC), especially in the tonsil, is caused by human papillomavirus (HPV), mainly HPV16. Noninvasive diagnostic methods to detect precancerous lesions in the tonsil would be useful, e.g., liquid-based cytology (LBC). However, ill-characterized precancerous lesions may be hidden in the depth of the tonsillar crypts. We therefore conducted a study on HPV and tonsillar precancerous lesions to evaluate, among other things, the utility of LBC obtained by deep brushing of the resected tonsils. Two hundred non-paediatric patients (mean age: 30.3 years) who underwent tonsillectomy for infection-related conditions (69%) or other conditions (mainly obstructive sleep apnoea, 31%) were included. An ultra-sensitive Luminex bead-based platform was used to test for the DNA of 21 mucosal HPV types; 56% of slides were unsatisfactory due to low number of squamous epithelial cells or the masking effect of a large number of lymphocytes. Three patients (1.5%; 95% CI: 0.5-4.3) showed suspicious cytological findings (atypical squamous cells-cannot exclude high-grade squamous intraepithelial lesion, ASC-H) while 3 others were HPV-positive (2 for HPV16 and 1 for HPV39). None of the ASC-H patients and HPV-positive patients showed dysplasia at histological examination. The rarity of HPV infection in the tonsil conflicts with the relatively frequent detection of the virus in the mouth. In conclusion, aggressive deep brushing of tonsils, while hardly applicable in vivo, is unlikely to be a reliable method to detect precancerous lesions. The absence of OPC screening modalities places the priority on multi-purpose primary prevention strategies, i.e., HPV vaccination and reduction of smoking and drinking.

Detection of HPV in oral rinse samples from OPSCC and non-OPSCC patients

Background

Due to the increasing rates of oropharyngeal cancer, oral HPV infection is a significant concern. Methods for detecting oral HPVs is not standardized as there are different techniques available. We propose that use of oral rinse samples to detect for HPVs is a suitable technique within a clinic setting. Thus, our main objective is to study HPV detection in oral rinse samples.

Methods

In our study, we used oral rinse sample collection coupled with real-time PCR to detect for HPVs types 16 and 18, and preferentially amplified FAP PCR samples to detect for a broad range of HPVs, in oropharyngeal squamous cell carcinoma (OPSCC), non-OPSCC, and healthy patients.

Results

Thirty three percent of 100 cancer patients were positive for any type of HPV; of those 23 were positive for HPV16. Only 1 of 110 healthy controls was positive (this subject was positive for HPV18).

Conclusion

Our results indicate that HPV detection in oral rinse samples may be useful as a screening tool to detect HPV-associated oral cancers.

Pilot study on the effects of high molecular weight sodium hyaluronate in the treatment of chronic pharyngitis

Although several therapeutic approaches are available at present for the treatment of chronic pharyngitis, new therapeutic strategies acting on pharyngeal mucous function should be investigated in order to improve symptoms and quality of life. High-molecular weight hyaluronate performs important functions on mucociliary clearance, tissues hydration, defense against micro-organisms, and on tissue repair as well, but at present there is no clinical evidence of its exogenous use in patients with chronic pharyngitis. Our open, randomized controlled study was carried out to investigate efficacy, and tolerability of exogenous high molecular weight sodium hyaluronate (SH) at the dosage of 9 mg three times a day for a period of 30 days, in patients with chronic pharyngitis. Results show significant improvements of symptoms and cytology in active group (A, n = 10) vs. control group (B, n = 10). Good compliance and no adverse events were reported in group A. In conclusion, SH was effective and safe in patients with chronic pharyngitis.

Optical coherence tomography and autofluorescence imaging of human tonsil

For the first time, we present co-registered autofluorescence imaging and optical coherence tomography (AF/OCT) of excised human palatine tonsils to evaluate the capabilities of OCT to visualize tonsil tissue components. Despite limited penetration depth, OCT can provide detailed structural information about tonsil tissue with much higher resolution than that of computed tomography, magnetic resonance imaging, and Ultrasound. Different tonsil tissue components such as epithelium, dense connective tissue, lymphoid nodules, and crypts can be visualized by OCT. The co-registered AF imaging can provide matching biochemical information. AF/OCT scans may provide a non-invasive tool for detecting tonsillar cancers and for studying the natural history of their development.

The role of cytology in the era of HPV-related head and neck carcinoma

Enlarged neck lymph nodes are very often subject to fine needle aspiration biopsy to detect metastatic disease in patients with suspected or proven squamous cell carcinoma in head and neck region. Cytology specimens of metastatic carcinoma in such patients are routinely evaluated for human papilloma virus (HPV) to identify patients with HPV-related head and neck squamous cell carcinoma. Different types of cytology specimens including smears, cytospins, cell blocks and aspirated material in the rinse can all be used for different types of HPV testing such as immunohistochemistry for p16, HPV-in situ hybridization, and HPV-Polymerase chain reaction. There is currently no consensus regarding the testing of high-risk HPV in cytology specimens. The establishment of standardized HPV testing of cytology specimens is of utmost importance and is eagerly awaited.

Epidemiology of HPV-associated oropharyngeal cancer

Squamous cell carcinoma of the oropharynx is increasing in incidence in epidemic proportion. This site specific increase in incidence is due to an increase in human papillomavirus (HPV)-related squamous cell carcinoma, while the incidence of tobacco related squamous cell carcinoma is decreasing. In particular, the incidence of HPV-related oropharyngeal squamous cell carcinoma (OPSCC) is increased among middle aged white men, and sexual behavior is a risk factor. HPV-related oropharyngeal squamous cell carcinoma represents a growing etiologically distinct subset of head and neck cancers with unique epidemiological, clinical, and molecular characteristics that differ from those of HPV-unassociated cancers. In this review, we discuss the epidemiology of HPV-related OPSCC, the prevalence of oral/oropharyngeal HPV infection, and efforts aimed at reducing the incidence of HPV-related OPSCC.

Human papillomavirus infection is rare in nonmalignant tonsil tissue in the UK: implications for tonsil cancer precursor lesions

The incidence of human papillomavirus (HPV)-associated tonsil cancer is increasing but the prevalence of HPV, and of premalignant precursors, in tonsil tissue is unknown. We aimed to assess prevalence of HPV infection in nonmalignant tonsillar crypt epithelia and to histopathologically characterise positive samples. Formalin-fixed paraffin-embedded (FFPE) tonsil tissue specimens were obtained from an age- and sex-stratified random sample of patients aged 0-69 years whose paired tonsils were archived following elective tonsillectomy at hospitals throughout England and Southern Scotland from 2004 to 2008. Homogenised fresh-frozen tonsil tissue was also obtained from archive for two random subsets of males aged 25-34 and over 44. HPV status was assessed in all samples for 20 mucosal HPV types by GP5+/6+ polymerase chain reaction (PCR) enzyme immunoassay and by HPV16 type-specific PCR targeting the E6 gene. In the homogenised material, HPV status was also assessed for 44 HPV types by SPF10-PCR enzyme immunoassay. Of 4,095 randomly sampled FFPE specimens, amplifiable DNA was extracted from 3,377 (82.5%) and from 511 of 524 (97.5%) homogenised tonsils. HPV DNA was identified in 0 of 3,377 (0%, 95% CI 0-0.089%) fixed samples and 0 of 511 (0%, 95% CI 0-0.58%) homogenised samples. This suggests HPV infection may be rare in tonsil reticulated crypt epithelia. Furthermore, we found no evidence of HPV-associated premalignant neoplasia. These data suggest that if HPV-associated premalignant lesions do occur, they are likely to be rare and may have a high risk of progression to carcinoma.

HPV-related cervical disease and oropharyngeal cancer

Human papillomavirus (HPV), especially HPV 16, is associated with the development of both cervical and oral cancer. We show the case of a woman affected by HPV-related cervical disease and oropharyngeal squamous cell carcinoma (OPSCC). A 41-year-old woman arrived at our Colposcopy Center following an abnormal Pap smear result (ASC-H) and a diagnosis of moderate cervical dysplasia obtained by a cervical biopsy. She underwent a colposcopy that showed a cervical abnormal transformation zone grade 2. A laser conization was performed in November 2010. Histology reported a moderate/severe dysplasia. The cone resection margins were free. Follow-up colposcopy and cytology were negative. The HPV testing showed an infection by HPV 16. In October 2012, the patient presented to the Head-Neck ER after episodes of hemoptysis; a lesion was found in the left tonsillar lodge. A biopsy was performed with a result of squamous cell carcinoma with low-grade differentiation. The HPV testing detected a high-risk HPV and the immunohistochemical analysis was positive for p16. She was treated by chemotherapy and brachytherapy. She was followed at the head-neck center with monthly visits with oral visual inspection that showed complete absence of mucosal abnormalities. HPV-related OPSCC and cervical precancerous/cancerous lesions have significant similarities in terms of pathogenesis. They are both caused largely by HPV 16, as in the present case. In conclusion, because of this association found in literature and in our case, we think that women with HPV cervical lesions should have regular surveillance for oropharyngeal cancer, whereas women with OPSCC should be encouraged to have diligent cervical screening.

Economic impact of human papillomavirus-associated head and neck cancers in the United States

Cases of human papillomavirus (HPV)-associated head and neck cancers are rapidly increasing in the United States. Little is known about the economic burden of these cancers. A literature review identified 7 studies that characterized aspects of the overall economic burden of HPV-associated head and neck cancers in the United States. Other cost studies are detailed to highlight the clinical reality in treating these patients. As the clinical awareness of the role of HPV in head and neck cancers continues, the economic impact of cancers caused by this virus will have implications for the role of various preventive measures.