Recurrent respiratory papillomatosis

Adjuvant Intralesional Bevacizumab in Pediatric and Adult Populations With Recurrent Respiratory Papillomatosis: A Systematic Review

OBJECTIVE

Recurrent respiratory papillomatosis (RRP) is a rare disease of the airway for which there is no known cure. Treatment involves the surgical removal or destruction of these lesions. There has been a long-standing debate over the effectiveness of the adjuvant intralesional injection of the immune modifying agent bevacizumab. This study is a systematic review investigating the effect of adjuvant intralesional bevacizumab on patients with laryngeal papillomatosis. The main objective was to assess functional outcomes and efficacy.

DATA SOURCES

Pubmed, Google Scholar, and Web of Science.

REVIEW METHODS

Search words were "intralesional bevacizumab" AND "recurrent respiratory papillomatosis." Sources were systematically identified using inclusion and exclusion criteria (ie, study publication must post-date 2000, must be peer-reviewed, investigate patients with RRP, apply bevacizumab intralesionally, not systemically). Findings were then collected and analyzed.

RESULTS

Ten studies were included for analysis. The majority of these studies found an increase in the surgical interval, voice outcomes, and a decrease in tumor burden in most patients. No studies reported side effects or lasting complications related to the bevacizumab injection.

CONCLUSION

This systematic review provides further evidence for the safety of intralesional bevacizumab injections and their likely positive effect on disease control. Future research would benefit from the implementation of standardized documentation of RRP outcomes.

Characterization of HPV6/11-reactive T-cell subsets in papillomas of patients with juvenile-onset recurrent respiratory papillomatosis and identification of HPV11 E7-specific candidate TCR clonotypes

Juvenile-onset recurrent respiratory papillomatosis (JORRP) is caused by persistent infection of epithelial cells by low-risk human papillomavirus (HPV) types 6 and 11. While multiple infiltrated immune cells have been reported to mediate disease progress, knowledge of HPV-reactive T-cell subsets in papillomas remains elusive. Through single-cell RNA sequencing and RNA microarray, we found that CD8+ tissue-resident memory T (CD8+ TRM) cells with strong interferon-gamma (IFN-γ) production expanded, and were negatively correlated to the disease severity in the frequency of surgery. These IFN-γ+ CD8+ memory T cells were readily activated and expanded in vitro by autologous dendritic cells loaded with HPV11 E7 peptide pool. Moreover, T cell receptor (TCR) clonal expansion was observed in JORRP papilloma tissues, indicating a biased TCR repertoire toward HPV-specific recognition. Finally, we identified and characterized HPV11 E7-specific candidate TCR clonotypes from IFN-γ+ CD8+ memory T cells, suggesting their potential application in TCR-engineered T cells (TCR-T) therapy for HPV11-related diseases. Our findings provided insights into the specific local immune response to HPV6/11 infection and highlighted the importance of IFN-γ+ CD8+ TRM cells in anti-HPV6/11 T-cell immunity.IMPORTANCEThe persistent recurrence of human papillomavirus (HPV) 6/11 infection in papillomas underscores the failure of local immune responses in patients with juvenile-onset recurrent respiratory papillomatosis (JORRP). Our previous study demonstrated that T cells constitute the predominant immune cell population in JORRP papilloma tissues. Understanding the T-cell-mediated immune responses within JORRP papilloma tissues is crucial for disease control. In the present study, we characterized CD8+ tissue-resident memory T (CD8+ TRM) cells as the primary T-cell subset responsible for local anti-HPV6/11 immunity. Moreover, we identified two HPV11 E7-specific candidate T cell receptor (TCR) clonotypes out of IFN-γ+ CD8+ memory T cells. Overall, our findings provided insights into the local immune responses to HPV6/11 infection and offered information for developing more effective immunotherapeutic strategies against JORRP.

Clinical evaluation of pediatric patients with recurrent respiratory papillomatosis.: A longitudinal study at a Saudi Arabian tertiary care center

OBJECTIVES

To study the clinical evaluation of recurrent respiratory papillomatosis (RRP) patients and the factors associated with the improvement in the Derkay's score as a measure of disease severity.

METHODS

A retrospective cohort that included all juvenile RRP patients who were admitted to King Abdulaziz University Hospital, Riyadh, Saudi Arabia, between September 2015 and June 2022 and underwent surgical debulking.

RESULTS

A total of 16 patients were eligible to join our study. Among them, 7 patients were males. Hoarseness of voice was the most frequent symptom. The median period of the follow-up was 56 months. Complete remission was achieved in 31.3%. The univariate linear regression model revealed that the cidofovir-treated patients had a significant reduction in the change value of Derkay's score compared to those without treatment (regression coefficient= -5.83, 95% confidence interval [CI]: [-11.5 to -0.143], p=0.045). Also, the increased first Derkay's score decreased the change value and subsequently increased the improvement chance of the disease (regression coefficient= -0.424, 95% CI: [-0.764 to -0.083], p=0.018). However, in the multivariate regression model, both variables showed non-significant results.

CONCLUSION

cidofovir treatment and higher Derkay's scores affected the disease improvement.

Diode Laser for Juvenile Recurrent Respiratory Papillomatosis: A Case Series of 13 Patients

Juvenile recurrent respiratory papillomatosis (JRRP) is the most common benign tumor in the larynx. It is uncommon; however, it is potentially life-threatening because it compromises the respiratory tract and required several surgeries to manage recurrences. Currently, the carbon dioxide laser is the treatment of choice. There are no studies about the role of the diode laser which is easy to use and has lower usage cost. This case series presentation reported on the therapeutic effects and recurrence rate of JRRP when using Diode laser. This is a case series presentation of 13 children, who were diagnosed with JRRP and operated for laryngeal papillomatosis with Diode laser in Otorhinolaryngology and Head and Nick Surgery Department et al. Mouwasat Hospital, Damascus, Syria between 2015 and 2022. 13 children required 56 surgeries at a rate of 1-2 surgeries/year, mean number of surgeries for each child was 4.31. That suggests that Diode laser might have a role in reducing the number of surgeries compared to a study used cold instrument and CO2 laser. The complications rate was 30.8%, which is considered a high rate compared to the other studies. In conclusion, we encourage using it when the CO2 laser device is not available. However, we suggest, reducing the power as low as possible and avoiding of two opposing raw surfaces, especially at the anterior commissure and deep excision. Further longitudinal studies are recommended to validate these results.

Efficacy of Systemic Bevacizumab for Recurrent Respiratory Papillomatosis with Pulmonary Involvement

OBJECTIVES

Pulmonary papillomatosis is a rare but severe manifestation of recurrent respiratory papillomatosis (RRP). Efficacy data of systemic bevacizumab for pulmonary RRP are limited. This study's objective was to characterize disease response of pulmonary RRP to systemic bevacizumab.

METHODS

A retrospective review was performed to identify patients with pulmonary RRP seen at three medical institutions. Clinical symptoms, CT findings, and disease response were compared before and after initiation of systemic bevacizumab therapy. Disease response was categorized as complete response, partial response, stabilization, or progression for each subsite involved by papilloma.

RESULTS

Of the 12 pulmonary RRP patients treated with systemic bevacizumab, 4 (33.3%) were male, and 11 (91.7%) were juvenile-onset RRP patients. All presented with laryngeal, tracheal, and pulmonary RRP. The median (range) age at first bevacizumab infusion was 48.1 (19.5-70.2) years. Progression to pulmonary malignancy was identified in 3 (25.0%) patients, 2 before initiation of and 1 after complete cessation of bevacizumab therapy. Clinical symptoms such as dyspnea (75.0% vs. 25.0%; p = 0.01) and dysphagia and/or odynophagia (33.3 vs. 0.0%; p = 0.03) were significantly decreased following bevacizumab therapy. Compared with pre-treatment baseline, 9 (75.0%) patients experienced a stable-to-partial response in the lungs to systemic bevacizumab, and 10 (83.3%) experienced partial-to-complete responses in the larynx and trachea.

CONCLUSION

Systemic bevacizumab is effective in stabilizing progression in even the most severe cases of RRP, with both a dramatic reduction in laryngeal and tracheal disease as well as a stable-to-partial response of pulmonary involvement in a majority of patients.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:577-581, 2024.

Autoinflammatory Keratinization Diseases-The Concept, Pathophysiology, and Clinical Implications

Recent advances in medical genetics elucidated the background of diseases characterized by superficial dermal and epidermal inflammation with resultant aberrant keratosis. This led to introducing the term autoinflammatory keratinization diseases encompassing entities in which monogenic mutations cause spontaneous activation of the innate immunity and subsequent disruption of the keratinization process. Originally, autoinflammatory keratinization diseases were attributed to pathogenic variants of CARD14 (generalized pustular psoriasis with concomitant psoriasis vulgaris, palmoplantar pustulosis, type V pityriasis rubra pilaris), IL36RN (generalized pustular psoriasis without concomitant psoriasis vulgaris, impetigo herpetiformis, acrodermatitis continua of Hallopeau), NLRP1 (familial forms of keratosis lichenoides chronica), and genes of the mevalonate pathway, i.e., MVK, PMVK, MVD, and FDPS (porokeratosis). Since then, endotypes underlying novel entities matching the concept of autoinflammatory keratinization diseases have been discovered (mutations of JAK1, POMP, and EGFR). This review describes the concept and pathophysiology of autoinflammatory keratinization diseases and outlines the characteristic clinical features of the associated entities. Furthermore, a novel term for NLRP1-associated autoinflammatory disease with epithelial dyskeratosis (NADED) describing the spectrum of autoinflammatory keratinization diseases secondary to NLRP1 mutations is proposed.

Smoking and Carcinoma Trends in Recurrent Respiratory Papillomatosis Patients

INTRODUCTION

Recurrent respiratory papillomatosis (RRP) is a chronic disease of the upper respiratory tract caused by human papillomavirus types 6 and 11. The disease course is characteristically unpredictable, ranging from spontaneous remission to aggressive, recurrent disease. Thus, management is often challenging and requires unique approaches tailored to each individual patient. While recent literature has described risk factors for more aggressive disease, few sources have investigated the impact of smoking on RRP disease course and risk for malignant transformation.

METHODS

A retrospective chart review was conducted for adult RRP patients evaluated at an academic tertiary care center between 2005 and 2020. A total of 188 patients were identified. Demographic and clinical data were collected, including smoking and alcohol history, HPV subtype, history of dysplasia and/or carcinoma, voice handicap index scores, Derkay scores, debulkings (in office and operating room), and days to papilloma recurrence.

RESULTS

Malignant degeneration in RRP occurred in 16.3% of smokers and 3.6% of nonsmokers. Smokers who developed carcinoma had less debulkings per years of evaluation than those not developing carcinoma (0.21 vs 0.92, P = .004). Additionally, patients that either presented with or developed carcinoma during their course had a higher pack-year smoking history (18.0 vs 12.21, P = .0002). No difference in days to recurrence or inter-surgical interval was demonstrated between smokers and nonsmokers.

CONCLUSIONS

The report demonstrates that smoking can increase the risk of malignant transformation in RRP patients.

Recurrent respiratory papillomatosis (RRP) of tracheobronchial tree presenting as lung collapse with malignant transformation after a decade

Recurrent respiratory papillomatosis is a rare disease caused by HPV infection. We hereby report a patient with recurrent respiratory papillomatosis of the tracheobronchial tree with no laryngeal involvement who remained clinically stable for more than 10 years but then developed malignant transformation with metastases. A 61-year-old lady with good past health presented to our department in 2010 because of chronic cough for years. Chest X-ray showed reduced left lung volume. Bronchoscopy showed multiple nodules over left main bronchus and left upper lobe progressing to involve the posterior trachea and left lower lobe. Biopsy revealed squamous papilloma with mild dysplasia. She refused surgical intervention. She remained relatively stable until November 2022 when she developed left chest pain. CT showed features of malignant transformation with local invasion and metastases. Fine needle aspiration suggested squamous cell carcinoma. She succumbed in December 2022. Bronchoscopy should be considered in the investigation of unexplained chronic cough so that this rare disease can be detected at an early stage. The disease may not require intervention if uncomplicated. Despite clinical stability for a prolonged period, close monitoring for malignant transformation is warranted indefinitely.

Recurrent laryngeal papillomatosis: multimodal therapeutic strategies. Literature review and multicentre retrospective study

Objectives

Recurrent respiratory papillomatosis (RRP) is a benign, rare disease caused by Human Papilloma Virus (HPV) that can be divided into juvenile and adult forms. The course of the disease is variable, but is usually more aggressive in the juvenile form. The standard surgical treatment is represented by CO2 laser resection, although photoangiolytic lasers represent a valid alternative. Adjuvant therapies have been proposed for disease control in case of frequent surgical resections or spreading into the lower airways. In recent years, the development of immunotherapy led to the use of bevacizumab either intratumorally or intravenously, but the most promising therapeutic development is represented by HPV vaccination. This paper aims to present a narrative review of the literature and the experience of three different University Centres in the treatment of RRP.

Methods

A retrospective analysis of the clinical charts of all patients affected by laryngeal papillomatosis and treated in three different University Centres between 2002 and 2022 was performed. The following parameters were collected: sex, age at first evaluation, sites of larynx involved, HPV type, type of first surgical treatment, presence and number of recurrences, surgical treatment of recurrences, adjuvant therapies, side effects and status at last follow-up.

Results

Seventy-eight patients were available for evaluation. Of these, 88% had adult onset RRP (Ao-RRP) and 12% juvenile onset RRP (Jo-RRP). The glottis was the most frequently involved subsite; all patients were submitted to surgical resection with CO2 laser under general anaesthesia. Recurrences appeared in 79% of the patients, the patients who did not recur were all adults. The mean number of recurrences was 9 (range 1-110). Recurrences were more frequent in children (M = 20; range 2-110) than adults (M = 5; range 1-21). Thirty-two (52%) of the 62 patients who recurred were re-treated with CO2 laser under general anaesthesia, while office-based treatment with a photoangiolytic laser was preferred in the remaining 30 (48%) patients. Adjuvant treatments were applied in 26 patients. The analysis of the course of the disease showed that in the 9 patients with Jo-RRP, 6 (67%) were free of lesions at the last follow-up, while the other 3 (33%) had papillomas. Of the 69 patients with Ao-RRP, 53 (77%) were alive and free of disease at the last visit, 14 (21%) were alive with disease, 1 (1%) was lost at follow-up and 1 (1%) died for other disease. Severe side effects were not observed except for 2 patients, who developed posterior glottic stenosis.

Conclusions

Our results confirmed the literature review. RRP is a potentially aggressive disease, especially in juvenile onset. Surgical resection is still first-line treatment, but in case of multiple recurrences the use of adjuvant therapies must be taken into consideration.

Molecular Mechanisms of Carcinogenesis in Pediatric Airways Tumors

Primary tumors of the airways in the pediatric population are very rare entities. For this reason, little is known about the pathogenesis of these neoplasms. Understanding the biology has different practical implications: for example, it could help in the differential diagnosis, have a prognostic significance, or may lead to the development of a targeted therapy. The aim of this article is to present the current knowledge about pediatric airways tumors, focusing on the molecular mechanisms that cause the onset and progression of these neoplasms. After a brief introduction of epidemiology and clinical presentation, the tumorigenesis of the most frequent pediatric airways tumors will be described: Juvenile-onset recurrent respiratory papillomatosis (JORRP), Subglottic Hemangiona (SH), Rhabdomyosarcoma (RMS), and Mucoepidermoid carcinoma (MEC).

Experience with Systemic Bevacizumab in Advanced Juvenile Recurrent Respiratory Papillomatosis

Vascular Endothelial Growth Factor has been demonstrated in squamous papillomas of Recurrent Respiratory Papillomatosis patients. This case series aimed at studying the feasibility and efficacy of systemic use of VEGF inhibitor Bevacizumab in advanced Juvenile Onset Recurrent Respiratory Papillomatosis (JORRP) patients. Three pediatric patients with advanced RRP were included in this study. A detailed bronchoscopic and radiological follow-up is presented. All patients responded well to the treatment. We conclude that systemic Bevacizumab can be tried as a feasible and rational adjuvant treatment in advanced JORRP patients.

Pulmonary manifestations of chronic HPV infection in patients with recurrent respiratory papillomatosis

Human papillomavirus (HPV) types 6 and 11 can infect the squamous epithelium of the respiratory tract. Up to 8·9% of patients with HPV-associated recurrent respiratory papillomatosis (RRP) have pulmonary involvement. Pulmonary manifestations of HPV infection are associated with considerable morbidity, in part because treatment options and management guidelines are lacking. Patients with pulmonary RRP have a 32-times increased lifetime risk of malignant transformation compared with the overall RRP population. We review the clinical and radiographic presentation, pathological features, and genetics of pulmonary RRP, and we provide management algorithms based on our clinical experience with this complex patient population. In patients with suspected pulmonary involvement, tissue-sparing procedures to address growing lesions might be warranted given the chronicity and multifocality of the disease over a patient's lifetime. However, malignant transformation of pulmonary lesion(s) warrants standard-of-care treatment for primary lung squamous cell carcinoma. Large cohort studies are needed to understand the clinical course of pulmonary RRP and to identify molecular markers of increased risk of malignant transformation in order to develop guidelines for optimal and standardised surveillance and treatment.

A Case of Recurrent Respiratory Papillomatosis With Lung Involvement and Malignant Transformation

Recurrent respiratory papillomatosis is a rare and complex progression of the disease due to the human papillomavirus (HPV). In this case report, we present the findings of a 53-year-old male who was diagnosed with obstructing respiratory papillomatosis of the trachea and underwent several procedures until the disease progressed to squamous cell carcinoma. Our objective with this case report is to contribute to a broader understanding of this disease by reporting a clinical case.

HPV and Recurrent Respiratory Papillomatosis: A Brief Review

Recurrent Respiratory Papillomatosis (RRP) is a rare but severe manifestation of human papillomavirus (HPV). As our knowledge about HPV infections has expanded, it has become possible to understand the course of RRP disease and unravel plausible efficient methods to manage the disease. However, the surge in reports on HPV has not been accompanied by a similar increase in research about RRP specifically. In this paper, we review the clinical manifestation and typical presentation of the illness. In addition, the pathogenesis and progression of the disease are described. On the other hand, we discuss the types of treatments currently available and future treatment strategies. The role of vaccination in both the prevention and treatment of RRP will also be reviewed. We believe this review is essential to update the general knowledge on RRP with the latest information available to date to enhance our understanding of RRP and its management.

Recurrent respiratory papillomatosis: clinical characteristics and viral genotyping in a Brazilian population

This study presents 25 cases of recurrent respiratory papillomatosis (RRP) that occurred in Sao Luis, Maranhao State, Northeast region, Brazil, between January 2007 and December 2018. Sociodemographic and clinical profile of patients as well as human papillomavirus (HPV) infection status were evaluated. Clinical and histopathological data were collected from the patients' medical records. For the HPV infection analysis, DNA was extracted and subjected to amplification by a nested polymerase chain reaction. Viral genotyping was performed by automated sequencing. The median age of patients was 12.40 ± 12.6. years, and the juvenile form of the disease (68%) was the predominant form of disease. Female participants were predominant (60%), and they were from cities located in the interior of the State (60%). The most common clinical manifestation was dysphonia; recurrence was observed in most cases (56%), and tracheostomy was necessary in seven patients (26.9%). When comparing the RRP forms, patients in the juvenile-RRP group had higher recurrence rates and need of tracheostomy than those in the adult-RRP group. The viral genotyping analysis revealed that 47.8% of patients had low-risk HPVs, whereas 13.1% had high-risk HPVs, and in 39.1% of patients the viral genotype was not obtained. HPV-6 was the most prevalent type and Juvenile-RRP was more prevalent in our population. HPV was present at a high rate, and HPV-6 was the predominant genotype. This study serves as the basis for further studies to be conducted in the Brazilian population. Our findings aid the better understanding of RRP, possibly suggesting some prognostic factors associated with the disease aggressiveness.

The Synthesis of Main Capsid Protein of Anogenital Type HPV6 L1 in Plant Expression System on the Basis of Tomato Fruits

The anogenital type HPV6 L1 major capsid protein was synthesized in a plant expression system on the basis of tomato fruits. The content of HPV6 L1 reached 380 μg per 1 mg of total soluble protein of raw fruit mass, which was represented as a single band with a molecular mass of 56 kDa on the SDS electrophoregram. When orally administrated to mice, the vaccine material from the tomato fruit transgenic for HPV6 L1 induced highly effective antibody immune response with a high titer. The cross-reactivity during the interaction of the antibody to the HPV6 L1 protein from peripheral blood serum of mice vaccinated with HPV6 L1 with the antigenic proteins HPV16 L1, HPV18 L1, HPV31 L1, and HPV45 L1 was found. This is promising for creating a vaccine with a broad reactivity against dangerous anogenital papillomatoses and cervical cancer.

Pembrolizumab Induced Acute Persistent Airway Disease in a Patient with Recurrent Respiratory Papillomatosis (RRP)

OBJECTIVE

To present an uncommon but serious, recently identified complication of checkpoint inhibitor therapy in a patient treated with pembrolizumab infusion for disseminated recurrent respiratory papillomatosis (RRP).

METHODS

Case report.

RESULTS

A 43-year-old woman with underlying asthma developed acute hypoxic respiratory failure within 24 hours of her third infusion of pembrolizumab for treatment of intractable, disseminated recurrent respiratory papillomatosis. Pulmonary function testing revealed a severe intra-thoracic obstructive ventilatory defect. Discontinuation of pembrolizumab, ventilatory support, and treatment with systemic and inhaled corticosteroids resulted in resolution of respiratory failure; however, her underlying asthma remains poorly controlled.

CONCLUSION

To our knowledge, this case is the first report of pembrolizumab-induced obstructive respiratory failure in a patient being treated for RRP.

Photobiomodulation and Antiviral Photodynamic Therapy in COVID-19 Management

Coronavirus disease 2019 (COVID-19) has shocked the world by its spread and contagiousness. There is no approved vaccine and no proven treatment for this infection. Some potential treatments that have already been associated with antiviral and anti-inflammatory effects are under investigation. Photobiomodulation therapy (PBMT) is a photon-based therapy that uses light to mediate a variety of metabolic, analgesic, anti-inflammatory, and immunomodulatory effects. Antiviral photodynamic therapy (aPDT) is a branch of photodynamic therapy based on the reaction between a photosensitizing agent and a light source in the presence of oxygen, which can produce oxidative and free radical agents to damage the viral structures such as proteins and nucleic acids. This chapter aims to discuss the potential therapeutic benefit of PBMT and aPDT in the context of the novel coronavirus. Studies indicate that PBMT and aPDT could be useful in many viral and bacterial pulmonary complications like influenza, SARS-CoV, and MERS, but we found no direct study on SARS-CoV-2. With a combination of PBMT and aPDT, we may be able to combat COVID-19 with minimal interference with pharmaceutical agents. It might improve the efficacy of PBMT and aPDT by using monoclonal antibodies and preparing new photosensitizers at the nanoscale that target the lung tissue specifically. More animal and human studies would need to take place to reach an effective protocol. This chapter would encourage other scientists to work on this new platform.

Estimated incidence of juvenile-onset recurrent respiratory papillomatosis in Korea

OBJECTIVES

Recurrent respiratory papillomatosis (RRP) is caused by human papillomavirus (HPV) types 6 and 11 and is potentially preventable through vaccination. This study estimated the incidence of juvenile-onset RRP before the implementation of the national HPV vaccination program in Korea.

METHODS

We conducted a cohort study using claims data provided by a mandatory insurance program to estimate the incidence of RRP and associated healthcare use. Patients with juvenile RRP were defined as those aged ≤12 years with ≥2 admissions or ≥2 outpatient visits during which they received the International Classification of Diseases, 10th revision code for benign neoplasms of the larynx (D14.1).

RESULTS

During 2002-2014, 123 children (74 boys and 49 girls) were diagnosed with RRP. The patients had a mean of 6.5 person-years of follow-up. The incidence was estimated at 0.30/100,000 person-years. The median age at diagnosis was 4.0 years (mean, 4.3). Thirty-six (29.3%) patients underwent surgery, including 23 patients (18.7%) who underwent 2 or more surgical procedures. Severe disease, measured by more frequent surgical procedures and shorter time intervals between consecutive operations, was associated with a younger age at diagnosis.

CONCLUSIONS

The estimated incidence of juvenile-onset RRP in Korea was similar to that reported in other countries. The RRP burden should continue to be monitored using National Health Insurance Service claims data.

Association between the TAP1 gene polymorphisms and recurrent respiratory papillomatosis in patients from Western Mexico: A pilot study

Background

Recurrent respiratory papillomatosis (RRP) is a respiratory tract disease that affects children and adults and is characterized by the recurrent proliferation of multiple papillomas. The etiologic agent is the human papillomavirus, mainly genotypes 6 and 11. Furthermore, polymorphisms in TAP1 appear to influence the selection of antigenic peptides and the transport process to the rough endoplasmic reticulum, for their subsequent presentation to T lymphocytes, an essential process against viral diseases and tumor processes. Previous studies have shown that individuals with those polymorphisms are susceptible to immune, infectious, and tumor‐related diseases. The present study aimed to determine the association between the TAP1 rs1057141 (c.1177A>G) and rs1135216 (c.2090A>G) single nucleotide polymorphisms (SNPs) and RRP.

Methods

A case–control study was carried out on a group of 70 individuals (35 controls and 35 patients). RRP diagnosis, HPV genotyping, and viral load were determined through histology and PCR. SNPs rs1057141 and rs1135216 were identified through allelic discrimination, using real‐time PCR. The haplotypic analyses were performed using the Arlequin 3.5 program.

Results

HPV‐6 and HPV‐11 were the genotypes found in the samples. In the polymorphism analysis, rs1057141 showed no significant differences (p = 0.049, CI = 0.994–7.331). In contrast, a significant difference was found in rs1135216 (p = 0.039, OR = 2.4) in the allelic analysis, as well as in the dominant (p = 0.027, OR = 3.06), codominant (p = 0.033, OR = 3.06), and additive model (p = 0.043, OR = 2.505) in subjects with the G allele.

Conclusion

The G allele in rs1135216 was associated with a genetic risk of susceptibility for RRP in a population in Western Mexico.

Patient-Derived Organotypic Epithelial Rafts Model Phenotypes in Juvenile-Onset Recurrent Respiratory Papillomatosis

Juvenile-onset recurrent respiratory papillomatosis (JoRRP) is driven by human papillomavirus (HPV) low-risk strains and is associated with significant morbidity. While previous studies of 2D cultures have shed light on disease pathogenesis and demonstrated the utility of personalized medicine approaches, monolayer cultures lack the 3D tissue architecture and physiology of stratified, sequentially differentiated mucosal epithelium important in RRP disease pathogenesis. Herein we describe the establishment of JoRRP-derived primary cell populations that retain HPV genomes and viral gene expression in culture. These were directly compared to cells from matched adjacent non-diseased tissue, given the known RRP patient-to-patient variability. JoRRP papilloma versus control cells displayed decreased growth at subconfluency, with a switch to increased growth after reaching confluency, suggesting relative resistance to cell-cell contact and/or differentiation. The same papilloma cells grown as 3D organotypic rafts harbored hyperproliferation as compared to controls, with increased numbers of proliferating basal cells and inappropriately replicating suprabasal cells, mimicking phenotypes in the patient biopsies from which they were derived. These complementary model systems provide novel opportunities to elucidate disease mechanisms at distinct stages in JoRRP progression and to identify diagnostic, prognostic and therapeutic factors to personalize patient management and treatment.

Human Papillomavirus-Associated Cancers

Human Papillomavirus (HPV) is the causative agent in the majority of anal, head and neck, oral, oropharyngeal, penile, vaginal, vulvar, and cervical cancers. Cervical cancer is the fourth most common cancer among women worldwide. Of all diagnosed human malignant neoplasms, approximately 4.5% are attributable to HPV, including cervical, anal cancers, vaginal, vulvar, penile, and oropharyngeal cancers. Over 182 HPV types have been identified and sequenced to date however, only certain types of HPV are more frequent in malignant lesions and considered to be a major risk factor in the development of some cancers. Because most HPV infections are transient, and an individual's immunocompetent may clear the infection, HPV infection has received little attention from clinicians, the general public, or policy makers. This lack of attention may underpin a deadly and increasing problem because each newly acquired infection has the potential to persist and become an incurable, lifelong affliction. In addition, no successful treatment of HPV infection currently exists despite the great strides toward understanding the mechanisms underlying HPV pathogenesis. Moreover, ample research has proven that the use of prophylactic vaccines, such as Gardasil and Cervarix, have led to documented progress in decreasing the burden of HPV infection, however not all countries introduced a government-funded National HPV Vaccination Program to protect young men and women. This chapter summarizes the HPV infection, detection and prevention. We also shed light on non-cervical HPV-related cancers, which is rapidly increasing in more developed countries toward cervical cancer.

An Experimental Model of Human Recurrent Respiratory Papillomatosis: A Bridge to Clinical Insights

OBJECTIVES/HYPOTHESIS

To investigate the growth pattern of recurrent respiratory papilloma (RRP) implants on chicken embryo chorioallantoic membranes (CAMs) and to evaluate possible associations between the clinical course of the disease and the behavior of experimentally implanted RRP tumors.

STUDY DESIGN

Experimental study.

METHODS

Fresh 172 RRP tissue samples from 12 patients were implanted onto chick embryo CAMs. Morphological and morphometric analysis of the experimental CAM and chorionic epithelium was performed. The microvascular network of the CAM with the RRP implant was investigated under the effect of fluoresceinated anionic dextran. The peculiarities of the clinical course of the disease were evaluated.

RESULTS

The implanted RRP tissue samples survived on CAMs in 86% of cases, retaining their essential morphologic characteristics and proliferative capacity of the original tumor. Implants induced thickening of both the CAM and the chorionic epithelium, but none of the RRP implants crossed the basement membrane of the hosting CAM. A "crawling film" of acellular material with newly formed papilloma sprouts located on the outer chorionic epithelium of the CAM was detected. Direct association between a recurrence rate of RRP and the number of newly formed papilloma sprouts around the implanted tumor on CAMs was revealed.

CONCLUSION

The chicken embryo CAM-based model is appropriate for investigations of RRP and facilitates the understanding of tumor biology and the clinical course of the disease, thus providing the basis for further research and acceleration of the identification and development of new specific therapeutic compounds that limit the spread and recurrence of RRP.

LEVEL OF EVIDENCE

N/A Laryngoscope, 131:E914-E920, 2021.

The Association of Human Papillomavirus in Benign and Malignant Laryngeal Lesions-a Pilot Study

Various etiological factors have been described in laryngeal carcinogenesis. Tobacco and alcohol play a major role in the development of laryngeal cancers. However, recently there has been an overshadowing of association of human papillomavirus infection in laryngeal cancers. The aim of this study is to assess the prevalence of human papillomavirus (HPV) in malignant laryngeal lesions. This is a case control study. We conducted this study using tumor tissue specimens from 30 laryngeal squamous cell carcinoma patients and benign laryngeal tissue specimens from 30 cancer-free controls. The specimens from the lesion were sent to histopathological analysis as well as DNA extraction (DNeasy® Tissue kit) and polymerase chain reaction for detection of HPV. Positive samples underwent sequencing to detect the HPV serotype. Statistical analysis was performed using SPSS software. All 30 benign laryngeal lesion specimens were negative for the HPV DNA, while 4 of the 30 (7.5%) squamous cell carcinoma lesions were positive. One was HPV 16 and another one HPV 11. Two positive cases were not able to be sequenced probably due to low viral load. Our study suggests that the proportion of laryngeal squamous cell carcinomas attributable to infection by HPV seems to be low. Further prospective studies should be conducted with a larger group of patients to confirm the role of HPV in laryngeal cancers especially in treatment response and survival.

Human genetic dissection of papillomavirus-driven diseases: new insight into their pathogenesis

Human papillomaviruses (HPVs) infect mucosal or cutaneous stratified epithelia. There are 5 genera and more than 200 types of HPV, each with a specific tropism and virulence. HPV infections are typically asymptomatic or result in benign tumors, which may be disseminated or persistent in rare cases, but a few oncogenic HPVs can cause cancers. This review deals with the human genetic and immunological basis of interindividual clinical variability in the course of HPV infections of the skin and mucosae. Typical epidermodysplasia verruciformis (EV) is characterized by β-HPV-driven flat wart-like and pityriasis-like cutaneous lesions and non-melanoma skin cancers in patients with inborn errors of EVER1-EVER2-CIB1-dependent skin-intrinsic immunity. Atypical EV is associated with other infectious diseases in patients with inborn errors of T cells. Severe cutaneous or anogenital warts, including anogenital cancers, are also driven by certain α-, γ-, μ or ν-HPVs in patients with inborn errors of T lymphocytes and antigen-presenting cells. The genetic basis of HPV diseases at other mucosal sites, such as oral multifocal epithelial hyperplasia or juvenile recurrent respiratory papillomatosis (JRRP), remains poorly understood. The human genetic dissection of HPV-driven lesions will clarify the molecular and cellular basis of protective immunity to HPVs, and should lead to novel diagnostic, preventive, and curative approaches in patients.

Trends in recurrent respiratory papillomatosis treatment

Recurrent respiratory papillomatosis (RRP) consist of benign tumours along the airway caused by human papillomavirus infection. Papillomas may cause changes in phonation and obstruct the airway. The purpose of this study was to evaluate the different surgical and adjuvant therapies available for the treatment of this condition reported between 2014-2018. A PubMed search was performed for RRP treatment articles published between 2014 -2018. Forty articles that encompassed 1425 patients with RRP met the criteria. Of these, 24 articles evaluate the use of adjuvant therapies such as bevacizumab, human papillomavirus vaccine and cidofovir. There has been an increase in adjuvant therapy options for RRP in the literature in recent years. An awareness of these options highlights gaps and opportunities in the care of these patients, opens the door to new protocols to control disease and increase intersurgical intervals, and guides us towards new management paradigms in the future.

Efficacy of microsurgery in combined with topical-PDT in treating recurrent respiratory papillomatosis: compare JORRP with AORRP

Background: Recurrent respiratory papillomatosis (RRP) remains a challenging and frustrating disease to treat.Objective: To explore the efficacy of microsurgery in combined with Topical-PDT in treating recurrent respiratory papillomatosis.Materials and methods: Fifty patients with RRP were treated with microsurgery in combined with Topical-PDT. Medical document of each patient was retrospectively reviewed. Detailed clinical information, metrics of clinical course, and current results were evaluated.Results: Juvenile onset RRP (JORRP) might experience a more aggressive course than AORRP (adult onset RRP) with higher Derkay score (p < .01) and higher operation frequency per year (p < .01). Microsurgical excision combined with Topical-PDT every 25 days achieved "remission" of disease in 78% of patients, "clearance" of disease in 52%, and "Cured" in two patients. Each patient who achieved "remission" of disease, performed 6.82 ± 3.39 operations, and continued 8.93 ± 7.03 months of treatment duration. No statistically differences were found in these two aspects between JORRP and AORRP. A negative correlation between tracheotomy and the efficacy of microsurgery in combined with Topical-PDT was found (p = .025, Pearson's r = -0.3).Conclusions and significance: Microsurgery in combined with Topical-PDT might be a powerful method to treat RRP. Tracheotomy is a negative factor for this therapy.

Homozygous NLRP1 gain-of-function mutation in siblings with a syndromic form of recurrent respiratory papillomatosis

Juvenile-onset recurrent respiratory papillomatosis (JRRP) is a rare and debilitating childhood disease that presents with recurrent growth of papillomas in the upper airway. Two common human papillomaviruses (HPVs), HPV-6 and -11, are implicated in most cases, but it is still not understood why only a small proportion of children develop JRRP following exposure to these common viruses. We report 2 siblings with a syndromic form of JRRP associated with mild dermatologic abnormalities. Whole-exome sequencing of the patients revealed a private homozygous mutation in NLRP1, encoding Nucleotide-Binding Domain Leucine-Rich Repeat Family Pyrin Domain-Containing 1. We find the NLRP1 mutant allele to be gain of function (GOF) for inflammasome activation, as demonstrated by the induction of inflammasome complex oligomerization and IL-1β secretion in an overexpression system. Moreover, patient-derived keratinocytes secrete elevated levels of IL-1β at baseline. Finally, both patients displayed elevated levels of inflammasome-induced cytokines in the serum. Six NLRP1 GOF mutations have previously been described to underlie 3 allelic Mendelian diseases with differing phenotypes and modes of inheritance. Our results demonstrate that an autosomal recessive, syndromic form of JRRP can be associated with an NLRP1 GOF mutation.

Topical 5-aminolevulinic acid photodynamic therapy for laryngeal papillomatosistosis treatment

BACKGROUND

To explore the therapeutic effect of topical 5-Aminolevulinic Acid photodynamic therapy (ALA-PDT) on laryngeal papillomatosis (LP) treatment.

METHODS

13 patients with LP underwent topical ALA-PDT after tumor resection (CO₂laser or/and microdebrider resection). All patients were irradiated 3-4 times. After ALA-PDT treatment, the laryngoscopic examination was performed every 1-2 months to observe the therapeutic effect.

RESULTS

All 13 patients were followed up for more than 1 year. Eleven cases (84.6%) showed no recurrence; two cases (15.4%) had relapses. One child developed III° inspiratory dyspnea caused by laryngeal mucosal edema and need endotracheal intubation again. Four patients had adhesion of the anterior commissure of the vocal cord. The detection rate of HPV infections was 76.9% and two patients had multiple HPV subtype co-infection.

CONCLUSIONS

The preliminary effect of topical ALA-PDT significantly reduces recurrence and improves the cure rate of LP. Further research on this treatment is still required.

Trends and targets in antiviral phototherapy

Photodynamic therapy (PDT) is a well-established treatment option in the treatment of certain cancerous and pre-cancerous lesions. Though best-known for its application in tumor therapy, historically the photodynamic effect was first demonstrated against bacteria at the beginning of the 20^th century. Today, in light of spreading antibiotic resistance and the rise of new infections, this photodynamic inactivation (PDI) of microbes, such as bacteria, fungi, and viruses, is gaining considerable attention. This review focuses on the PDI of viruses as an alternative treatment in antiviral therapy, but also as a means of viral decontamination, covering mainly the literature of the last decade. The PDI of viruses shares the general action mechanism of photodynamic applications: the irradiation of a dye with light and the subsequent generation of reactive oxygen species (ROS) which are the effective phototoxic agents damaging virus targets by reacting with viral nucleic acids, lipids and proteins. Interestingly, a light-independent antiviral activity has also been found for some of these dyes. This review covers the compound classes employed in the PDI of viruses and their various areas of use. In the medical area, currently two fields stand out in which the PDI of viruses has found broader application: the purification of blood products and the treatment of human papilloma virus manifestations. However, the PDI of viruses has also found interest in such diverse areas as water and surface decontamination, and biosafety.

Position statement for the diagnosis and management of anogenital warts

BACKGROUND

Anogenital warts (AGW) can cause economic burden on healthcare systems and are associated with emotional, psychological and physical issues.

OBJECTIVE

To provide guidance to physicians on the diagnosis and management of AGW.

METHODS

Fourteen global experts on AGW developed guidance on the diagnosis and management of AGW in an effort to unify international recommendations. Guidance was developed based on published international and national AGW guidelines and an evaluation of relevant literature published up to August 2016. Authors provided expert opinion based on their clinical experiences.

RESULTS

A checklist for a patient's initial consultation is provided to help physicians when diagnosing AGW to get the relevant information from the patient in order to manage and treat the AGW effectively. A number of frequently asked questions are also provided to aid physicians when communicating with patients about AGW. Treatment of AGW should be individualized and selected based on the number, size, morphology, location, and keratinization of warts, and whether they are new or recurrent. Different techniques can be used to treat AGW including ablation, immunotherapy and other topical therapies. Combinations of these techniques are thought to be more effective at reducing AGW recurrence than monotherapy. A simplified algorithm was created suggesting patients with 1-5 warts should be treated with ablation followed by immunotherapy. Patients with >5 warts should use immunotherapy for 2 months followed by ablation and a second 2-month course of immunotherapy. Guidance for daily practice situations and the subsequent action that can be taken, as well as an algorithm for treatment of large warts, were also created.

CONCLUSION

The guidance provided will help physicians with the diagnosis and management of AGW in order to improve the health and quality of life of patients with AGW.

Management of laryngeal papillomatosis using coblation: another option of surgical intervention

PURPOSE

Recurrent respiratory papillomatosis is a disease caused by the human papilloma virus (HPV). HPV is frequently localised in the larynx. The disease tends to recur and frequent intervention is usually required. Management modules include surgical intervention using microdebriders or laser ablation as well as adjuvant treatments which aim mainly at maintaining an adequate airway and secondly to manage dysphonia caused by the growth on the vocal folds. In this pilot study, another surgical modality is trialled using plasma-mediated radio-frequency ablation (coblation).

METHODS

Retrospective study examining management of 15 adult patients diagnosed with recurrent laryngeal papillomatosis and surgically treated using coblation. One patient required multiple procedures. Pre-operative assessment in voice clinic evaluating voice quality and its impact on patients' life-quality using voice parameters and self-assessment questionnaires. Follow-up post-operatively using the same parameters from 4 to 6 weeks after surgery until up to 2 years later to check recurrence rate. No other adjuvant treatment was used and all patients received post-operative voice therapy.

RESULTS

78.6% of patients did not show evidence of recurrence during the study period. Improvement in voice handicap following first intervention is reported and recurrence rate in the rest of the sample reported.

CONCLUSIONS

The results of this small sample seem to support the previous small studies' findings that coblation is a good excisional technique to use for removal of laryngeal papillomatosis. Recurrence rates seem to be slightly lower than rates reported in the literature for the other surgical modalities.

LEVEL OF EVIDENCE

IV.

Histologic effect of the potassium-titanyl phosphorous laser on laryngeal papilloma

Objectives

Tissue effects occurring with potassium‐titanyl phosphorous (KTP) laser treatment are difficult to quantify due to the multiple variables that affect not only the fluence (energy delivered) but also the laser–tissue interaction. This histopathologic analysis of recurrent respiratory papilloma (RRP) removed after treatment with KTP laser therapy permits correlation of histologic effect with method of laser treatment.

Methods

The histopathology of RRP resected specimens in a single patient was compared following treatment with KTP laser in contact and non‐contact modes as documented with intraoperative photography and video imaging.

Results

Epithelial‐sparing injury selective to the microvasculature was identified on histopathologic assessment of a specimen treated with noncontact angiolysis. Highly cauterized papillomatous epithelium without identifiable vascular structures was identified on tissue removed after treatment with the KTP laser in contact mode.

Conclusion

The histopathologic assessment of acute KTP laser effect on papilloma permits correlation between technique of application and tissue effect. Similar assessments may be helpful to modify dosimetry for individual patients requiring repeated treatment and may also assist in refining the development of existing KTP laser treatment classification systems.

Level of Evidence

4

MVA E2 therapeutic vaccine for marked reduction in likelihood of recurrence of respiratory papillomatosis

Background

Recurrent respiratory papillomatosis (RRP) or laryngeal papillomatosis is a disease caused by papillomavirus infection.

Methods

In this phase I/II clinical trial, we evaluated the efficacy of the modified vaccinia Ankara (MVA) E2 virus in the treatment of RRP. Twenty‐nine patients (18 female and 11 male) underwent injection of MVA E2 directly into the borders of the vocal cords where lesions were seen and were monitored by direct laryngoscopy. The immune response was assessed by the determination of CD3⁺, CD4⁺, and CD8⁺ lymphocytes counts. The presence of papillomavirus was determined by polymerase chain reaction analysis.

Results

Lesions were completely eliminated in 13 patients (44.8%). In 16 patients (55.2%), lesions recurred between 6 and 18 months after treatment; these patients received a second round of treatment with MVA E2, and they are not seen with new recurrences.

Conclusion

The MVA E2 vaccine has excellent potential for generating complete regression of RRP lesions.

Laryngotracheobronchial papillomatosis: chest CT findings

To evaluate the findings on chest CTs in 16 patients (8 men and 8 women) with laryngotracheobronchial papillomatosis.

Transformation of Recurrent Respiratory Papillomatosis: Squamous Cell Carcinoma in a Pregnant Teen

Recurrent respiratory papillomatosis is a rare intractable benign disease with a bimodal age distribution. We present a rare case of malignant transformation of juvenile-onset recurrent respiratory papillomatosis in a 19-year-old pregnant woman, who was found to have a right upper lobe mass and cavitary nodules bilaterally that were biopsy proven to be node-negative, multifocal squamous cell carcinoma. In her second trimester, she underwent video-assisted thoracoscopic right upper lobectomy and middle lobe lateral segmentectomy, followed by left lower lobe segmentectomy 0 months later. Recovery was uneventful, and she remains disease-free 1 year following both resections.

Safety and Immunogenicity of a Nonadjuvant Human Papillomavirus Type 6 Virus-like Particle Vaccine in Recurrent Respiratory Papillomatosis

OBJECTIVES

To assess the safety and immunogenicity of a nonadjuvant human papillomavirus (HPV) type 6 L1 virus-like particle (VLP) vaccine in recurrent respiratory papillomatosis (RRP) in local Chinese patients.

METHODS

Patients with RRP who had undergone surgical treatment before intramuscular administration of an escalating dose of HPV type 6 L1 VLPs (1, 5, and 25 µg at 4 weekly intervals) as part of their treatment were followed up for more than 10 years. Efficacy was assessed by detecting the vaccine-induced type-specific antibody titer, calculating the intersurgical interval, and observing recurrence or remission of papillomas after receiving the vaccine.

RESULTS

Nonadjuvant HPV vaccine was generally well tolerated, with no serious vaccine-related adverse episodes. It induced seroconversion for each vaccine-related HPV type. At week 12 (4 weeks after injecting 25 µg), the vaccine-induced type-specific antibody titer was significantly high. Analysis of all patients found a significant increase in the intersurgical interval and decrease in the scores. One patient (16.7%; female) experienced complete remission. Five patients (83.3%) (two males and three females) experienced partial remission. In total, complete or partial remission was achieved in six (100%) patients.

CONCLUSIONS

Administration of nonadjuvant HPV type 6 L1 VLPs vaccine to RRP was generally well tolerated and highly immunogenic.

HPV vaccination as preventive approach for recurrent respiratory papillomatosis - a 22-year retrospective clinical analysis

BACKGROUND

Recurrent respiratory papillomatosis (RRP) is a rare, benign disease of the aerodigestive tract, especially the larynx, caused by infection with the human papillomavirus (HPV) types 6 or 11. Current management focuses on surgical debulking with microdebrider of papillomatous lesions with or without concurrent adjuvant therapy, e.g. Cidofovir®. This retrospective study evaluates the results of patients treated at a department of the university clinic between 1990 and 2012 and compares the results of the conventional treatment with a new treatment approach using adjuvant vaccination with Gardasil®.

METHODS

A retrospective Kaplan Maier analysis of n = 24 patients diagnosed and treated with RPR was performed. The records were reviewed for gender, age at the time of first manifestation of disease and time to recurrence.

RESULTS

Only n = 2 (15.4%) of the n = 13 vaccinated patients developed a recurrence of the disease after a mean time of 54.9 months (SD: 9.5 months). All patients who were not vaccinated (n = 11; 100%) developed a relapse after a mean time of 12.3 months (SD: 9.72 months).

CONCLUSION

We propose that adjuvant HPV vaccination with Gardasil® might have a preventive effect in RRP by occluding new papilloma formation.

Clinical and sociodemographic characteristics associated with disease severity in juvenile recurrent respiratory papillomatosis: A study of 104 patients in a tertiary care pediatric hospital

BACKGROUND

Juvenile recurrent respiratory papillomatosis (JRRP) is generally aggressive and with a high recurrence rate. Currently, there is no definite curative treatment for JRRP. Therefore, a greater understanding of the aspects that influence the severity and prognosis of the disease is required.

OBJECTIVE

The aim of this study was to establish the clinical and socioeconomic characteristics of pediatric patients with JRRP and its relationship with the severity of the disease in a tertiary care pediatric hospital.

RESULTS

A strong relationship was observed between the severity of the disease and the age at the time of diagnosis, and having a tracheostomy. A moderate association was found between the severity of the disease and the age at the time of the study, the area of origin and the recurrence rate. None of the socioeconomic statuses had a correlation with the severity of the JRRP.

CONCLUSIONS

JRRP is associated with multiple surgeries due to the recurrence and aggressiveness of the disease. The socioeconomic status does not seem to influence the severity of the disease, whereas younger patients and users of tracheostomy should receive a more strict follow-up given the increased risk of severe disease.

A Young Adult with Cough and Wheezing Since Infancy

A 20-year-old man presented for outpatient evaluation of treatment options for recurrent respiratory papillomas. He was born with vocal cord paralysis. At 4 weeks of life, he underwent tracheostomy. In childhood his tracheostomy was closed, and he was found to have occasional, small papillomas in the trachea. During puberty, he experienced a dramatic increase in the number and size of the papillomas.

Host control of human papillomavirus infection and disease

Most human papillomaviruses cause inapparent infections, subtly affecting epithelial homeostasis, to ensure genome persistence in the epithelial basal layer. As with conspicuous papillomas, these self-limiting lesions shed viral particles to ensure population level maintenance and depend on a balance between viral gene expression, immune cell stimulation and immune surveillance for persistence. The complex immune evasion strategies, characteristic of high-risk HPV types, also allow the deregulated viral gene expression that underlies neoplasia. Neoplasia occurs at particular epithelial sites where vulnerable cells such as the reserve or cuboidal cells of the cervical transformation zone are found. Beta papillomavirus infection can also predispose an individual with immune deficiencies to the development of cancers. The host control of HPV infections thus involves local interactions between keratinocytes and the adaptive immune response. Effective immune detection and surveillance limits overt disease, leading to HPV persistence as productive microlesions or in a true latent state.