Human papillomavirus type 11 DNA in squamous cell carcinomas and pre-existing multiple laryngeal papillomas

Human papillomavirus co-infection and survival in oral and oropharyngeal squamous cell carcinoma: A study in 235 Brazilian patients

OBJECTIVES

While unknown for oropharyngeal squamous cell carcinoma (OPSCC) and oral squamous cell carcinoma (OSCC), some studies assessing cervical carcinoma have shown that human papillomavirus (HPV) co-infection can be associated with its prognosis.

METHODS

Through in situ hybridization (HPV and Epstein-Barr virus [EBV] probes) and immunohistochemistry (p16^INK4a, cyclin D1, p53, and Ki-67 antibodies), 126 OPSCC and 109 OSCC samples were assessed.

RESULTS

All patients were EBV-negative. OPSCC (25%) showed a significant association with HPV compared to OSCC (11%). Almost all HPV-associated cases were p16^INK4a-positive. Regarding OPSCC and OSCC, 23 and 7 cases were positive for high-risk HPV (HRHPV) only, 6 and 3 cases for low-risk HPV (LRHPV) only, and 3 and 2 cases for HRHPV/LRHPV, respectively. HPV-associated carcinomas showed a significantly higher proliferative index than HPV-unassociated carcinomas. Both carcinomas showed a similar overall survival rate, which was not affected by the HPV status. However, when comparing HPV-associated subgroups, patients with HRHPV/LRHPV-associated carcinomas showed worse survival.

CONCLUSION

LRHPV-associated and HRHPV/LRHPV-associated cases can also be detected when assessing OSCC and OPSCC. Further studies, especially in populations with a high prevalence of HPV-associated OPSCC, are necessary to understand the clinicopathological behavior of these neoplasm subgroups.

Co-expression of low-risk HPV E6/E7 and EBV LMP-1 leads to precancerous lesions by DNA damage

Background

Low-risk human papillomavirus (HPV), such as types 6 and 11, is considered non-oncogenic, but these types have been detected in oral cancer tissue samples, suggesting their possible involvement in oral carcinogenesis. Because double infection of high-risk HPV and Epstein-Barr virus (EBV) is known to be involved in oral carcinogenesis, we hypothesized that low-risk HPV and EBV co-infection can transform the oral cells. To verify our hypothesis, we evaluated the transformation activity of cell lines expressing both low-risk HPV E6/E7 and EBV LMP-1.

Methods

We transduced HPV6, 11 and 16 E6/E7 genes and EBV LMP-1 gene into primary mouse embryonic fibroblasts. The cell lines were examined for indices of transformation activity such as proliferation, induction of DNA damage, resistance to apoptosis, anchorage-independent growth, and tumor formation in nude mice. To evaluate the signaling pathways involved in transformation, NF-κB and p53 activities were analyzed. We also assessed adhesion signaling molecules associated with anchorage-independent growth such as MMP-2, paxillin and Cat-1.

Results

Co-expression of low-risk HPV6 E6 and EBV LMP-1 showed increased cell proliferation, elevated NF-κB activity and reduced p53 induction. Moreover, co-expression of low-risk HPV6 E6 and EBV LMP-1 induced DNA damage, escaped from apoptosis under genotoxic condition and suppression of DNA damage response (DDR). Co-expression of low-risk HPV11 E6/E7 and EBV LMP-1 demonstrated similar results. However, it led to no malignant characteristics such as anchorage-independent growth, invasiveness and tumor formation in nude mice. Compared with the cells co-expressing high-risk HPV16 E6 and EBV LMP-1 that induce transformation, co-expression of low-risk HPV6 E6 and EBV LMP-1 was associated with low MMP-2, paxillin and Cat-1 expression.

Conclusions

The co-expression of low-risk HPV E6/E7 and EBV LMP-1 does not induce malignant transformation, but it allows accumulation of somatic mutations secondary to increased DNA damage and suppression of DDR. Thus, double infection of low-risk HPV and EBV could lead to precancerous lesions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08397-0.

HPV Strain Predicts Severity of Juvenile-Onset Recurrent Respiratory Papillomatosis with Implications for Disease Screening

Juvenile-onset recurrent respiratory papillomatosis (JoRRP) is the most common benign neoplasm of the larynx in children, presenting with significant variation in clinical course and potential for progression to malignancy. Since JoRRP is driven by human papillomavirus (HPV), we evaluated viral factors in a prospective cohort to identify predictive factors of disease severity. Twenty children with JoRRP undergoing routine debridement of papillomas were recruited and followed for ≥1 year. Demographical features, clinical severity scores, and surgeries over time were tabulated. Biopsies were used to establish a tissue bank and primary cell cultures for HPV6 vs. HPV11 genotyping and evaluation of viral gene expression. We found that patients with HPV11+ disease had an earlier age at disease onset, higher frequency of surgeries, increased number of lifetime surgeries, and were more likely to progress to malignancy. However, the amplitude of viral E6/E7 gene expression did not account for increased disease severity in HPV11+ patients. Determination of HPV strain is not routinely performed in the standard of care for JoRRP patients; we demonstrate the utility and feasibility of HPV genotyping using RNA-ISH for screening of HPV11+ disease as a biomarker for disease severity and progression in JoRRP patients.

Risk factors for the development of high-grade dysplasia and carcinoma in patients with laryngeal squamous cell papillomas: Large retrospective cohort study

BACKGROUND

The incidence and risk factors for the development of high-grade dysplasia (HG-D) and laryngeal squamous cell carcinoma (LSCC) were assessed in patients with laryngeal squamous cell papillomas (LSP).

METHODS

Clinical data, human papillomaviruses (HPV) typing, HPV E6/E7 mRNA in situ hybridization, and sequencing of host genes in LSP biopsies of 163 patients were analyzed.

RESULTS

Progression to HG-D and LSCC was identified in 21.5% and 4.3% of LSP patients, respectively. A more advanced age at LSP onset and lack of HPV infection were detected as risk factors for the development of HG-D and LSCC (P < .05). The identification of HG-D was associated with its progression to LSCC (P < .05). Host gene mutations were identified in 3 of 7 patients with LSCC.

CONCLUSIONS

The histological monitoring of LSP and HPV typing are necessary for early detection of epithelial changes. Further research is needed to elucidate the role of host gene mutations in LSCC transformation.

Squamous Cell Carcinoma Originating from Adult Laryngeal Papillomatosis: Case Report and Review of the Literature

Background

The malignant transformation of laryngeal papillomatosis (LP) into squamous cell carcinoma (SCC) can occur in up to 4% of LP cases. The low-risk HPV types 6 and 11 are those that are most commonly related to LP; however, high-risk HPV types may be present. The present study reviews the literature on cases of malignant transformation of LP in adults and reports a clinical case.

Case Report

A 47-year-old male patient exhibiting hoarseness for 4 months presented an exophytic lesion in the right palatine tonsil and a digitiform-like lesion in the right vocal fold. The biopsy revealed a well-differentiated SCC in the vocal cord, which showed a transition zone with a squamous papillomatous lesion. By using the chromogenic in situ hybridization (CISH) test, both lesions showed a positive result for high-risk HPV types 16 and 18 and negative for low-risk HPV types 6 and 11. The final diagnosis was SCC arising from LP. The patient underwent surgical treatment. After 36 months of follow-up, no signs of recurrence were observed.

Results

The literature review revealed 25 cases of malignant transformation into SCC of LP with adult onset. Of these, only 9 cases were assessed by CISH and/or PCR for HPV identification, of which 7 were positive. The current study focuses on the eighth case, suggesting the involvement of the high-risk HPV types in its pathogenesis.

Conclusions

LP is considered a benign lesion with the potential for malignant transformation, which reinforces the need for its early diagnosis and the constant monitoring of patients with LP.

HPV in Head and Neck Cancer-30 Years of History

The interesting history of papillomavirus (PV) research has been reviewed before. The history of human papillomavirus (HPV) in head and neck region starts in 1901 when the contagious transmission of warty lesions into the mouth via oral sex was described, although the confirmation of their viral etiology had to wait until 1907. Ullman was the first to associate the human wart virus with laryngeal warts. Parsons and Kidd described the natural history of oral PV infections in rabbits already in 1942, but these findings were corroborated in humans only recently. Koilocytotic atypia described by Koss and Durfee in 1956 was recognized as a sign of HPV infection in cervical precancer lesions only in 1976-1977 (Meisels and Fortin; Purola and Savia). This prompted systematic surveys of head and neck lesions for the detection of koilocytosis since the late 1970s, and the authors of this communication were the first to propose the HPV involvement in a subgroup of head and neck cancers. Brandsma and Abramson demonstrated HPV16 DNA in tonsillar SCCs in 1989. Since the early 2000s, HPV research of head and neck squamous cell carcinomas (HNSCC) has made impressive progress, confirming that the specific anatomic site plays a key role in determining the susceptibility to HPV infection. The most likely cancer sites associated with HPV are the base of the tongue and palatine tonsils, followed by oral cavity, larynx, and sinonasal mucosa. There is substantial geographic variation in HPV association with HNSCC. Patients with HPV-associated HNSCC are younger, and survival is better than in the absence of HPV.

A case of recurrent respiratory papillomatosis with malignant transformation, HPV11 DNAemia, high L1 antibody titre and a fatal papillary endocardial lesion

Background

Recurrent respiratory papillomatosis (RRP) is a rare disease, which is characterised by the growth of papillomavirus-induced papillomas within the respiratory tract. Malignant transformation occurs in less than 1% of the cases.

Case presentation

We report a case of human papillomavirus (HPV) type 11-associated juvenile-onset RRP (JORRP) initially diagnosed at the age of two years. Remarkably high copy numbers of HPV11 DNA and antibody titres targeting the capsid protein L1 were detected in the patient’s serum. The patient developed squamous cell carcinomas in both lungs and extraordinarily an HPV11 DNA-positive papillary endocardial lesion in the left atrium of the heart, which caused thromboembolic events leading to the patient’s death at 19 years old.

Conclusion

We here report a severe case of JORRP hallmarked by HPV11 DNAemia and very high antibody titres directed against the major viral capsid protein L1. Furthermore, the extent of malignant transformation and the discovery of a very rare fatal endocardial lesion highlight the unpredictability of JORRP and the complexity of its clinical management.

Recurrent respiratory papillomatosis: HPV genotypes and risk of high-grade laryngeal neoplasia

Patients with recurrent respiratory papillomatosis (RRP) in Norway treated between 1987 and 2009 were recruited to this cohort study. They were followed from disease onset and data recorded until January 2012. Here, we describe the distribution of human papillomavirus (HPV) genotypes, the prevalence of multiple HPV infections, and the risk of high-grade laryngeal neoplasia and respiratory tract invasive carcinoma in a large cohort of patients with RRP. We also examined whether HPV genotype, gender, age or clinical course are risk factors for this development. Clinical records and histological specimens were reviewed. Using formalin-fixed paraffin-embedded biopsies, HPV genotyping were performed by quantitative polymerase chain reaction assays identifying 15 HPV types. HPV-negative specimens were analyzed by metagenomic sequencing. Paraffin blocks were available in 224/238 patients. The DNA quality was approved in 221/224 cases. HPV DNA was detected in 207/221 patients and all were HPV 6 or HPV 11 positive, comprising HPV 6 in 133/207, HPV 11 in 40/207 cases and HPV 6/11 in 15/207 cases. Co-infection with one or two high-risk HPV types together with HPV 6 or HPV 11 was present in 19/207 patients. Metagenomic sequencing of 14 HPV-negative specimens revealed HPV 8 in one case. In total, 39/221 patients developed high-grade laryngeal neoplasia. 8/221 patients developed carcinoma of the respiratory tract (six patients with laryngeal carcinoma and two patients with lung carcinoma). High-grade laryngeal neoplasias were found more frequently in HPV-negative versus HPV-positive patients, (RR = 2.35, 95% CI 1.1, 4.99), as well as respiratory tract carcinomas (RR = 48, 95% CI 10.72, 214.91). In summary, the majority of RRP were associated with HPV 6 and/or 11. HPV-negative RRP biopsies occurred more frequently in adult-onset patients, and were associated with an increased risk of laryngeal neoplasia and carcinoma in the respiratory tract.

HPV associated with recurrent respiratory papillomatosis

Papillomaviruses are members of the Papillomaviridae family. Over 150 HPV types have been identified. Recurrent respiratory papillomatosis (RRP) is a chronic condition caused by HPV characterized by recurrent papillomas of the respiratory tract, mainly the larynx. During the early stages, the condition presents with hoarseness, while more advanced disease presents with stridor and respiratory distress. There is no specific cure and treatment consists of repeated surgical procedures to remove the papillomas. Most patients eventually go into remission, but some suffer for many years with this condition, which may be fatal. HPV-6 and HPV-11 are the HPV types most commonly associated with RRP. Although most studies have found RRP due to HPV-11 to be more aggressive than disease due to HPV-6, the variability in disease aggressiveness is probably multifactorial. Information regarding the current epidemiology, molecular diversity and host immune responses is important for strategizing ways to reduce disease. Data on HPV genotypes associated with RRP would provide valuable information for vaccination programs to reduce the incidence of these genotypes in mothers and, in the long term, reduce the incidence of RRP in children. This review focuses on HPV-6 and HPV-11 as the HPV types that cause RRP, and discusses the viral genome and replication, clinical presentation of RRP, current techniques of diagnosis and genotyping, and the molecular diversity of HPV-6 and HPV-11.

Current concepts on human papillomavirus infections in children

Current evidence is strong enough to conclude that human papillomavirus (HPV) can be transmitted both sexually and non-sexually. The debate on HPV infections in children still continues but it is more focused on HPV prevalence than on transmission modes. HPV DNA detection in amniotic fluid, foetal membranes, cord blood and placental trophoblastic cells all suggest HPV infection in utero, i.e. prenatal transmission. Based on recent meta-analysis, vertical transmission occurs in approximately 20% of cases. Most of the mucosal HPV infections in infants are incident, persistent infections in oral and genital mucosa being found in less than 10% and 2% respectively. The mother seems to be the main transmitter of HPV to her newborn, but subsequent HPV infections are acquired horizontally via saliva or other contacts. Bimodal peak prevalence is seen for skin warts, oral papillomas and recurrent respiratory papillomatosis (RRP) in younger and older age groups, suggesting similar epidemiology. Of the clinical HPV diseases, juvenile-onset-RRP and genital condylomata are problematic; the former because of its life-threatening potential and the latter because of possible sexual abuse. HPV6 and 11 are the most common genotypes in both the lesions. Early in life, infections by the high-risk HPV genotypes may also remain persistent for a considerable period, and should be of considerable importance for HPV vaccination strategies.

The role of HPV type in Recurrent Respiratory Papillomatosis

OBJECTIVE

Human Papillomavirus (HPV) 6 and 11 are the aetiological agents responsible for Recurrent Respiratory Papillomatosis (RRP). There is general consensus that HPV11 results in more aggressive disease compared to HPV6.

METHOD

Pubmed was searched using the terms respiratory papillomatosis, HPV 6 and HPV11. Comparisons were made in the outcomes of HPV6 versus HPV11 positive RRP disease.

RESULTS

There are numerous sub-types or variants of both HPV6 and HPV11. These sub-types have different activities at least in-vitro. The numbers of different HPV types within RRP tissue may be more extensive than initially appeared. This depends specifically upon the HPV types tested for.

CONCLUSION

The clinical differences between HPV6 and HPV11 disease may not be accurately predictable as these viruses exist in numerous sub-types. Also, RRP tissue may contain more than one subtype or even be co-infected with other viruses that may influence outcome. In-vitro studies upon cell lines are a reasonable starting point for evaluation of these differences.

Side-effects of cidofovir in the treatment of recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is a chronic and difficult to treat disease of the larynx. In 1998, the first article was published that described the use of the antiviral substance cidofovir to treat this disease. Although the results are promising, there remains some concern about the potential carcinogenicity of cidofovir. There is a demand for a qualitative review of the side-effects of this medicine. In this review, the side-effects of cidofovir are investigated. Special attention was given to the potential carcinogenicity of cidofovir. For this review a search is performed in PubMed and EMBASE for relevant articles in which the use of intralesional cidofovir for patients with RRP is described. Eventually, 31 articles could be included for this review. In these articles a total of 188 patients with RRP were described who underwent therapy with intralesional cidofovir. Five of these patients have developed dysplasia of the larynx during the treatment with cidofovir. This is a percentage of 2.7. This percentage is concurrent with the incidence of spontaneous malignant degeneration of RRP (2–3%). Based on this review, it can be concluded that the use of intralesional cidofovir does not increase the risk of laryngeal dysplasia. Apart from the articles that describe the intralesional administration of cidofovir, some articles have been published in which the use of intravenous cidofovir is described as a therapy for RRP. Therefore, a summary is given on the side-effects of intralesional cidofovir as well as a summary on the reported side-effects of the intravenous administration of cidofovir. Based on the outcomes of this review, recommendations are given for a safe use of cidofovir for treatment of recurrent respiratory papillomatosis in the future.

Recurrent respiratory papillomatosis – the Manchester experience, 1974–1992

A series of 59 patients of all ages with recurrent respiratory papillomatosis (RRP) treated over an 18-year period is presented. A number of these patients were initially diagnosed in childhood but required treatment throughout adult life. The frequency of laser treatment was not related to either disease duration or age at onset. In 28 patients, the HPV type was identified, showing that HPV type 11 was more common in children and ran a more protracted clinical course. The requirement for tracheostomy in this series was small, whereas the incidence of malignant change in adult patients was significant

Human papillomavirus in head and neck cancer: Molecular biology and clinicopathological correlations

Human papillomaviruses are known to cause cancers of the cervix and other anogenital tract sites. Epidemiologic and molecular pathology studies have also suggested that HPV infection may be associated with cancers of the head and neck. Modes of transmission of HPV infection in the head and neck region have not been fully resolved; however, perinatal transmission and an association between sexual behavior and risk for HPV-positive cancers have been presented. Among the HPV types infecting the mucosa, high-risk, intermediate-risk and low-risk genotypes are defined, depending on their presence in carcinoma or precursor lesions. The phylogenic groups of HPVs also showed a definite correlation with the morphology of head and neck tumors. The groups A6, A7, and A9 include viruses that are frequently demonstrated in basaloid and verrucosus squamous cell carcinomas known to associate with HPV infection. Integration of HPV DNA into the host cell genome occurs early in cancer development and is an important event in malignant transformation. There is a trend for patients with HPV-positive tumors to be nondrinkers or light drinkers, the majority of these patients are females, and the median age is lower than in the case of HPV-negative tumors, but this latter difference was not always statistically significant. In the Kaplan-Meier survival model, the HPV-positive verrucous and basaloid squamous cell carcinomas showed better survival rates than the HPV-negative typical squamous cell carcinomas. An increased radiocurability of HPV-positive head and neck squamous cell carcinoma (HNSCC) has also been demonstrated.

Direct gene transfer into rat articular cartilage by in vivo electroporation

To establish a system for efficient direct in vivo gene targeting into rat joint, we have evaluated a strategy of gene transfer by means of the delivery of external electric pulses (EP) to the knee after intra-articular injection of a reporter gene (GFP). Rats were killed at various times after the electro gene-therapy to analyze GFP gene expression by immunohistochemistry. GFP staining was detected in the superficial, middle, and deep zones of the patellar cartilage at days 2 and 9, and thereafter only in the deep zone (months 1 and 2). The average percentage of GFP-positive cells was estimated at 30% both one and 2 months after the gene transfer. Moreover, no pathologic change caused by the EP was detected in the cartilage. The level and stability of the long-term GFP expression found in this study demonstrate the feasibility of a treatment of joint disorders (inflammatory or degenerative, focal or diffuse) using electric gene transfer.

Molecular Events in the Progression of Recurrent Respiratory Papillomatosis to Carcinoma

Context.—Identification of the type of human papillomavirus (HPV) by polymerase chain reaction and sequencing to determine coinfection or superinfection (by more than 1 HPV type) and other molecular events have not been reported in a series of patients exhibiting the morphologic spectrum of recurrent respiratory papillomatosis progressing to carcinoma.

Design.—Four cases of juvenile-onset recurrent respiratory papillomatosis progressing to carcinoma (no history of smoking or irradiation in 2 cases) were studied. Morphologically distinct foci (squamous papilloma, pulmonary papillomatosis, squamous dysplasia subjacent to carcinoma, and squamous carcinoma) were subjected to laser capture microdissection and polymerase chain reaction amplification using general primers in addition to type-specific primers for HPV types 16 and 18. Direct sequencing of polymerase chain reaction products identified the type of HPV. The tissue sections were immunostained using antibodies to p53, pRb, p21WAF1, and p16 proteins with a semiquantitative assessment.

Results.—Human papillomavirus 11 was the only type of HPV identified in all lesions of all cases associated with recurrent respiratory papillomatosis. There was a marked increase in p53 protein expression in foci of dysplasia and carcinoma as compared to squamous papilloma and pulmonary papillomatosis. An inverse correlation between p53 and p21WAF1 protein expression was noted in all lesions. pRb protein expression increased from the benign to the malignant end of the spectrum. p16 protein was expressed in all lesions.

Conclusions.—Infection by HPV-11 may be an early event associated with progression of recurrent respiratory papillomatosis to carcinoma. Increased expression of p53 and pRb proteins and a reduced expression of p21WAF1 protein appear to be significant subsequent events.

Human papillomavirus in larynx

OBJECTIVES

The core of the present clinical and basic research knowledge of laryngeal human papillomavirus (HPV) infection is described.

STUDY DESIGN

Review.

METHODS

A computer-aided search of MEDLINE database supplemented by hand searches of key journals was conducted.

RESULTS

One of the tumor-promoting factors in the larynx is the HPV found both in normal laryngeal epithelium and in laryngeal tumors. The most important manifestation of laryngeal HPV infection is laryngeal papillomatosis, a rare disease caused by HPV types 6 and 11. In laryngeal carcinogenesis, the role of HPV remains uncertain. The means of transmission of HPV are partly unknown, and the course of laryngeal HPV infection is unpredictable and variable. Treatment of laryngeal papillomatosis is based on surgery, especially on CO2 laser and shaver. Alpha-interferon is the drug of choice in patients whose response to surgery is poor. However, neither interferon nor other antiviral drugs are able to eradicate the virus from laryngeal mucosa. Little is known about immunological mechanisms involved in laryngeal HPV infection, but in defense against HPV cellular immunity is considered a more important mechanism than humoral immunity. A good experimental model of HPV infection is lacking in which the entire viral life cycle can take place. Organotypic cell cultures (collagen rafts) are useful, but the rate-limiting step in this method is the difficulties in culturing HPV-positive epithelial cells.

CONCLUSIONS

Although laryngeal papillomatosis is clinically well defined, the mechanisms and treatment modalities of laryngeal HPV infection need further investigations.

Powered laryngeal shavers and laryngeal papillomatosis: a preliminary report

Carbon dioxide (CO2) laser ablation is widely accepted as the most effective first line surgical treatment of recurrent laryngeal papilloma. However, vaporization of papilloma with the CO2 laser exposes the patient and staff to a potentially infective plume. Furthermore, unsuitable pathological tissue specimens and scarring of the surrounding laryngeal architecture are inevitable consequences of the thermal energy generated by this instrument. Following their innovative use in endonasal surgery, powered laryngeal microresecting instruments (Xomed Shavers) have been developed for laryngeal surgery. We assessed the value of these new instruments in five patients who had previously undergone laser ablation. All of the patients reported that their postoperative recovery was the 'same as' or 'better than' that following laser surgery. The surgeon reported that though there was more bleeding, shaver excision of papilloma provided good clearance of disease; easy collection of pathological samples; and a potentially safer and faster alternative to laser excision.

Multiple papilloma larynx

Multiple papilloma of larynx is caused by human papilloma virus. We treated sixteen such cases (10 males and six females) in the last 10 years. All presented with hoarseness while six presented with difficulty in respiration. Three patients needed tracheostomy, all had difficult decanulation, and one developed laryngotracheal stenosis and could not be decanulated. All were treated by surgical excision; ten had recurrence. Four patients were treated with post operative Acyclovir with no recurrence in three cases.

Squamous cell carcinoma arising in recurrent respiratory papillomatosis with pulmonary involvement: emerging common pattern of clinical features and human papillomavirus serotype association

Squamous papillomas of the lung are an uncommon feature of recurrent respiratory papillomatosis, occurring in fewer than 1% of cases. We describe a 23-year-old patient with pulmonary papillomas who developed a fatal squamous cell carcinoma of the lung. PCR-based human papillomavirus (HPV) typing showed the presence of HPV 11 DNA in both benign papillomas and invasive carcinoma. A review of the literature reveals four reports of malignant transformation of juvenile-onset recurrent respiratory papillomatosis in which HPV typing was performed. Similar clinical features are noted in all of the reports; specifically, each case has arisen in a young adult man with a history of papillomatosis since childhood. In each of the cases, HPV 11 was identified in association with the squamous cell carcinoma. Although HPV 11 is uncommonly associated with the development of invasive carcinoma at other sites, these findings suggest that it is correlated with malignant transformation in the setting of juvenile-onset recurrent respiratory papillomatosis.

Solitary squamous cell papilloma of the lung in a 40-year-old woman with recurrent laryngeal papillomatosis

A rare case of recurrent respiratory papillomatosis (RRP) is reported with a review of the literature. A 40-year-old Japanese woman had suffered from RRP since 1 year of age. She developed a pulmonary squamous papilloma with a thin-walled cavity, which was suspected as being lung carcinoma. The trachea and bronchi around the tumor were intact, and no malignant transformation was present. Two types of human papillomavirus, 6 and 16, were detected, both in the laryngeal and pulmonary papillomas by in situ hybridization and the polymerase chain reaction method. To date, only 40 cases of juvenile laryngeal papilloma with pulmonary involvement have been reported in the English literature.

Laryngeal cancer and human papillomavirus: HPV is absent in the majority of laryngeal carcinomas

Thirty laryngeal carcinomas from patients without pre-existing laryngeal papillomatosis were examined by PCR for the presence of HPV DNA. The utmost care was taken during sectioning of the tissue blocks and DNA-extraction in order to avoid false positive results. Three pairs of consensus primers were used: MY9/MY11, GP5+/GP6+ and CPI/CPII. HPV was detected in 1/30 carcinomas. The HPV type present could not be determined, but it was not type 6, 11, 13, 16, 18, 30, 31, 33, 35 or 45. In other studies the reported frequency of HPV in laryngeal carcinomas, as estimated by PCR, varies between 3-85%. The reasons for this unacceptable variation in reported results are discussed. The present results indicate that HPV DNA does not have a major role in malignant tumours of the larynx in patients without pre-existing recurrent laryngeal papillomatosis.

High-risk human papillomavirus types and squamous cell carcinoma in patients with respiratory papillomas

Respiratory papillomas (RPs) are benign, virally induced tumors of the larynx and respiratory epithelium that may obstruct the airway and tend to recur frequently. RPs are thought to be the result of infection with the human papillomaviruses (HPVs) types 6 and 11. We surveyed archival RP specimens to determine whether there were correlations of HPV type with patient characteristics or clinical course. Paraffin-embedded papilloma specimens of 45 different patients were analyzed. We assessed HPV types using the polymerase chain reaction with E6 consensus primers, hybrid capture assays (high or low risk), and dot blot hybridization of generic E6 PCR products with E6 type-specific oligonucleotide probes. The presence and type of HPV were correlated with patient data from a retrospective chart review. We found that RPs may have either low- or high-risk HPV types and some contain multiple HPV types. Respiratory infection with high-risk HPV apparently introduces a long-term risk of squamous cell carcinoma development, even in the absence of conventional cofactors. Low-risk HPV infection may also act in association with these cofactors to promote carcinogenesis. Our data also show a racial imbalance in RP that may indicate a difference in genetic resistance and/or susceptibility to HPV infection and the development of RP.

Detection of human papillomavirus (HPV) in laryngeal carcinoma cell lines provides evidence for a heterogeneic cell population

The role of human papillomavirus (HPV) has been studied in laryngeal carcinomas with contradictory results. To evaluate the causal relationship between HPV infection and epithelial malignancies of the larynx, 27 laryngeal carcinoma cell lines from 22 patients were studied. Also, paraffin-embedded biopsy samples of the original tumours were available from 12 patients. First, Southern blot hybridisation (SBH) was used for the analysis of 18 cell lines and 12 original tumour sections were studied by in situ hybridisation (ISH) to detect HPV. Further, cell lines and tumour biopsy samples were investigated with polymerase chain reaction (PCR) using three sets of consensus primers directed to L1 and E1 ORFs (open reading frames) and type-specific primers to HPV 16 E6 region. The adjacent apparently normal epithelium of one original biopsy sample showed positive signals for HPV by ISH. All other samples were HPV negative with these methods. The study was then extended to 27 laryngeal carcinoma cell lines, including the 18 cell lines studied earlier. A new nested PCR method was used with MY as external and general primers (GP) as internal primers for the cell lines and original tumour samples to achieve a maximal sensitivity. Subsequent SBH was performed to confirm the specificity of PCR products with both low- and high-risk HPV oligonucleotide probe mixtures and also with the HPV 16 oligoprobe. With this method, seven of 27 (26%) cell lines and seven of 12 (58%) tumour samples were found to harbour high-risk HPV. In two cases both the original tumour sample and the derived cell line showed HPV positivity. These results indicate that HPV copy numbers are low and only a minority of tumour cells harbour HPV DNA, explaining partly the controversial results reported earlier.

An aggressive and invasive growth of juvenile papillomas involving the total respiratory tract

A malignant course of juvenile laryngeal papillomatosis has rarely been reported. In the present case the patient had had laryngeal papillomas since the age of three years. The papillomas gradually spread to the entire respiratory system, and during 30 years the patient was operated on more than 80 times. At present an invasive tumour spreading from the tongue into the parapharyngeal space, extending to the cranial base, has been demonstrated by magnetic resonance imaging (MRI). Intralesional therapy with Cidofovir, a promising antiviral drug against human papillomavirus (HPV) infection, was started with some clinical effect, although only on the superficial tumour growth. Histology of removed tumour tissue has demonstrated a mixture of exophytic and inverted growth pattern, and has mainly been interpreted as benign, in spite of a focally high mitotic index and an intermittent lack of maturation in the epithelium. In the most recent biopsies a verrucous carcinoma has been diagnosed. Expression of p53 was noted to increase in papillomas with time. All samples have been shown to harbour HPV 11, but no other HPV types.

A novel method to culture laryngeal human papillomavirus-positive epithelial cells produces papilloma-type cytology on collagen rafts

A novel method to culture human papillomavirus (HPV) positive laryngeal epithelial cells is described. Biopsies of laryngeal papillomas and of HPV-positive laryngeal mucosa were first cultured as a monolayer in which irradiated laryngeal fibroblasts originally derived from a papilloma (PPLF-XR) patient served as feeder cells. When these fourth or fifth passage epithelial cells were transferred to allow growth on an organotypic growth base (collagen raft containing unirradiated PPLF), they grew as a multilayer. This layer showed features typical of HPV infection with koilocytosis, parakeratosis, and isolated dyskeratotic cells. Based on in situ hybridisation, the original tumour sections and epithelial cells from each monolayer passage, as well as the collagen raft sections, contained HPV DNA. Our results show that HPV-infected epithelial cells can be maintained during passages in monolayer culture and that PPLF can support the growth of these cells well. The monolayer cell culture and the collagen raft, the latter providing differentiation-promoting effects, appears to facilitate maintenance of the infected cells and of the viral genome.

Malignant transformation of recurrent respiratory papillomatosis associated with integrated human papillomavirus type 11 DNA and mutation of p53

Recurrent respiratory papillomatosis (RRP), usually confined to the nasopharynx, trachea, and larynx, occasionally can progress to extensive bronchopulmonary disease. Most cases of bronchopulmonary and laryngeal papillomatosis are cytologically benign and do not undergo malignant transformation; however, squamous cell carcinoma (SCC) can arise in RRP in the absence of known risk factors such as radiation and smoking. In this study, the authors investigated molecular genetic alterations occurring in a case of metastasizing SCC that arose in long-standing bronchopulmonary papillomatosis. Genomic DNA from tracheal papillomata, tracheobronchial papillomata, SCC of the lung, and a lymph node metastasis was extracted. The physical state of the human papillomavirus type 11 (HPV-11) DNA was investigated by two-dimensional gel electrophoresis. Molecular genetic alterations of the host genome were studied by direct sequencing of polymerase chain reaction-amplified gene fragments and restriction fragment length polymorphism (RFLP) analysis. Episomal and integrated forms of HPV-11 sequences were detected in histologically benign tumors, but only the integrated form of the viral DNA could be found in malignant tissue samples. Molecular genetic studies revealed that an allelic loss of the interferon-beta gene (IFNbeta-1) and an endogenous type of mutation of the p53 antioncogene were found only in the malignant lesions. Mutations were not observed in the ras, neu, or multiple tumor suppressor (MTS1/p16) genes in any specimens. The authors' data indicated that the p53 genetic mutation was associated with integration of HPV-11 in histologically malignant lesions. This association may promote a progressive genetic instability that can lead to the development and clonal expansion of malignant lesions in RRP.

Prognostic value of clinical findings in histologically verified adult-onset laryngeal papillomas

A retrospective study of adult-onset laryngeal papilloma was performed to clarify whether any clinical features at the time of diagnosis could predict its course. All patients had a histologically confirmed diagnosis of laryngeal papillomas and were treated at Helsinki University Hospital between 1975 and 1994. Those with adult-onset disease and follow-up exceeding 1 year (n = 74) entered the study. Based on the case records surveyed, results suggested two risk factors for frequent laryngeal procedures: young age at onset of papilloma and a lesion extending to the anterior third to the vocal folds. It was not possible to predict the course of the disease by such clinical findings as symptoms or size or number of primary papilloma lesions. As regards the recurrence of disease, the classic division of adult-onset laryngeal papilloma into solitary and multiple type was not found to be clinically relevant.

Recurrent respiratory papillomatosis

Juvenile-onset recurrent respiratory papillomatosis is a vertically transmitted disease caused by members of the human papilloma virus family. Characterized by the relentless growth of papillomatous lesions of the larynx, recurrent respiratory papillomatosis imposes significant morbidity on patients and strain on their families. Surgical excision of the papillomata remains the mainstay of therapy, but human papilloma virus DNA persists in adjacent, normal-appearing mucosa and likely serves as a reservoir for viral reseeding. Despite multiple adjuvant treatment modalities, a cure for recurrent respiratory papillomatosis remains elusive. Most afflicted patients eventually enter spontaneous remission, but some endure several hundred surgical procedures before this welcome respite.

A possible role for human papillomaviruses in head and neck cancer

Human papillomaviruses (HPVs) cause benign tumors in the respiratory tract. Mounting evidence suggests that they also play a role in the etiology of a subset of head and neck cancers. Carcinomas in patients with a history of recurrent respiratory papillomatosis clearly are caused by persisting HPV interacting with one of more carcinogenic agents. Verrucous carcinomas of the oral cavity, tonsillar and tongue carcinomas are strongly linked with HPVs, based on molecular epidemiologic data. Tonsillar cancer have been shown to express HPV RNA, presumed necessary to induce and maintain a carcinoma, supporting a viral etiology. This paper reviews the molecular and cellular basis for considering HPVs as causative agents of cancer, and reviews the literature that considers the possible role of HPVs in head and neck cancer.

Adult respiratory papillomatosis: human papillomavirus type and viral coinfections as predictors of prognosis

Pathologic material and the records of 29 patients with laryngeal papillomatosis were reviewed. The relationship between the type of human papillomavirus (HPV) and the presence of viral coinfections was correlated with clinical outcome. Using polymerase chain reaction, paraffin-embedded specimens were analyzed for the presence of HPV, Epstein-Barr virus (EBV), cytomegalovirus (CMV), and herpes simplex virus (HSV). The HPV type could be identified in 24 patients' specimens. Twenty-one patients were infected with HPV type 6. The other 3 were infected with HPV type 11 or 16. Three patients developed squamous cell carcinoma, of whom 2 had HPV type 11 or 16. We found HSV, EBV, and CMV in 50%, 12.5%, and 0% of specimens, respectively. An aggressive clinical course was observed in 17 patients. Evidence of coinfection with other viruses was identified in 11 (65%) of these patients. In contrast, a benign clinical course was observed in 7 patients, of whom 2 (29%) had viral coinfections. We conclude that the HPV type and the presence of viral coinfections may be predictive of an aggressive clinical course.

Diet-modified sex hormone metabolism: is this the way forward in recurrent respiratory papillomatosis and squamous carcinoma prophylaxis?

We report two cases of recurrent laryngeal papillomatosis in women who subsequently developed squamous cell carcinoma as they approached the climacteric. The role of human papilloma virus (HPV) and oestrogen metabolism is outlined. The use of indoles from cruciferous vegetables is also discussed.

Lack of detection of human papillomavirus (HPV) in transformed laryngeal keratoses by in situ hybridization (ISH) technique

Laryngeal keratosis (LK) is a precancerous mucosal change with a variable possibility of malignant transformation. Recent studies evidencing HPV-DNA genomes in a large series of non-malignant and malignant laryngeal lesions suggest a role of HPV in the transformation of laryngeal lesions possibly in synergistic interaction with other carcinogens. In this study, we analyzed 115 biopsy specimens from benign laryngeal lesions to evaluate the risk of malignant transformation and its relationship to degree of dysplasia and to histological features of virus cell infection. The rate of transformation of LK was 8% (9/115). Our results indicate that the risk of transformation in laryngeal keratoses without dysplasia (LKWOD) is lower than that in laryngeal keratoses with dysplasia (2.2% vs 25%, respectively) (p < 0.05). An increased risk of malignant evolution in laryngeal keratoses with dysplasia (LKWD) was also related to the degree of dysplasia (rate of transformation of 12.5, 22.2 and 36% in mild, moderate and severe dysplasia, respectively). Histological features suggesting HPV infection (koilocytic-like atypia and epithelial papillary hyperplasia) were found in 6 LK only, no case subsequently developing cancer. In both benign and transformed LK, analyzed by ISH, we failed to detect HPV genomes, suggesting a major role of others carcinogens, such as tobacco and/or alcohol, in the transformation of LK.

Antibody response to a synthetic peptide derived from the human papillomavirus type 6/11 L2 protein in recurrent respiratory papillomatosis: correlation between Southern blot hybridization, polymerase chain reaction, and serology

Recurrent respiratory papillomatosis (RRP) is the most common benign tumour of the larynx, affecting both children and adults. We present a series of 25 patients, including 10 cases of juvenile multiple, 8 cases of adult solitary, and 7 cases of adult multiple RRP. Biopsy tissue from each patient was screened by Southern blot hybridization and polymerase chain reaction for the presence of human papillomavirus (HPV) DNA. Sera from patients and age- and sex-matched controls were tested for the presence of HPV-specific antibodies using a synthetic peptide derived from the minor capsid protein (L2) of HPV 6/11. By Southern blot hybridization and/or polymerase chain reaction, biopsies from all patients were positive for HPV 6/11 DNA. There was no difference in antibody response between cases and controls. Female cases and controls had significantly higher antibody titers than male subjects. A correlation was observed between the HPV-specific antibody level and the number of surgery-necessitating recurrences.

Human papillomavirus in laryngeal papillomas and in adjacent normal epithelium

Eleven adults with laryngeal papillomas were studied for the presence of human papillomavirus (HPV) DNA by in situ hybridization. As well as from the papillomas, three additional biopsies were taken from the normal-appearing mucosa as follows: the involved vocal cord, the opposite vocal cord (when the papilloma was unilateral), and from the ventricular fold on the side of the lesion. These normal tissues were analysed by polymerase chain reaction (PCR) to detect HPV DNA. All except one of the 11 papillomas contained HPV DNA; nine were HPV 6/11 DNA positive and one positive for HPV 16 DNA. The normal-appearing laryngeal mucosa harboured HPV DNA in eight out of 11 patients. The present results strongly support the concept that the adult-type laryngeal papilloma is an HPV-induced lesion, mostly due to HPV types 6 and 11. The persistence of HPV DNA in the adjacent normal epithelium is consistent with the frequent recurrence of these lesions.

Analysis of prevalence of human papillomavirus in laryngeal carcinomas. Study of 40 cases using polymerase chain reaction and consensus primers

In this study we determined the frequency of association of human papillomavirus (HPV) and laryngeal carcinomas and investigated the possibility that HPV may be associated with larger or more aggressive tumors. Laryngeal squamous cell carcinomas from 40 patients who did not have preexisting papillomas by clinical history were retrieved from formalin-fixed, paraffin-embedded blocks and analyzed for HPV. Twenty-two cases were tumors of the true vocal folds, and 18 were supraglottic. Clinical follow-up was available for 25 patients. We used the polymerase chain reaction (PCR) with the "hot start" modification and consensus primers that can detect over 30 distinct HPV types. Three of the 40 patients (8%) had detectable HPV DNA. These 3 patients did not have unusual age demographics and were smokers. All but 1 of the 22 HPV-negative patients who were questioned were also smokers. We compared the outcomes for large (4 cm or greater) HPV-positive and -negative tumors. Six of the 40 tumors were 4 cm or greater and involved contiguous structures. Two of these 6 were HPV-positive, and these patients died of disease after 3 and 16 months, respectively. Of the 4 HPV-negative patients with tumors greater than 4 cm, 3 are disease-free at 41, 42, and 3 months, respectively, and 1 was lost to follow-up. The third HPV-positive patient had a tumor less than 1 cm, and is disease-free after 38 months. While the number of HPV-positive cases is too small for definitive conclusions, it is possible that for large tumors the presence of HPV DNA may portend a worse prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of ras oncogene mutations in human squamous cell carcinoma of the head and neck

The presence of proto-oncogene mutations at codons 12, 13 and 61 of the Ha-, Ki-, and N-ras in primary head and neck squamous cell carcinoma are analysed in this study. Oncogene ras-specific sequences were amplified by the polymerase chain reaction and probed with mutation specific oligonucleotide probes. Mutations were detected in 8 of 22 samples (36.3%). No mutations were detected on patients' peripheral blood DNA. We found that histologically and clinically, squamous cell carcinomas with or without a ras mutation do not differ significantly from each other.

Hypnotherapeutic intervention for voice disorders related to recurring juvenile laryngeal papillomatosis

Recurring juvenile laryngeal papillomatosis is resistant to cure, and thus usually requires multiple operations which may lead to the extensive proliferation of vocal fold scar tissue. Severe hoarseness, sharply lower pitch, and weak loudness levels are common sequelae. Adjunctive hypnotherapy can increase motivation for change, speed up the acquisition of vocal skills, and possibly even facilitate or sustain remission of growths in selected patients. An 8-year-old girl with severe active eruptions went into remission after 16 sessions, and a 12-year-old boy, already in remission at the beginning of the intervention period, remained free of neoplasms throughout the regimen. Whether or not hypnosis contributed significantly to the sanguine results, it is probable that, at the least, the hypnotic intervention facilitated the achievement of certain technical objectives in voice therapy.

In situ hybridization and laryngeal papillomas

The technique of in situ hybridization with biotin-labeled probes was applied to 20 patients with laryngeal papillomatosis (9 with adult-onset disease and 11 with juvenile-onset). Ten patients were noted for epithelial transformation of their laryngeal disease. All patients, regardless of their clinical outcome, tested positive for human papillomavirus group 6/11. The biotin method of in situ hybridization proved to be a sensitive method in this study, identifying the infecting viral group in 23 of 24 samples. This study also tested for group 16/18 and is the first to test for the presence of group 31/33/35 in the larynx. These viruses or members of related groups have been reported in malignancies of the head and neck as well as the uterine cervix. They have yet, however, to be identified in benign laryngeal papillomas or laryngeal papillomas that have undergone epithelial transformation.

Laryngeal precancer: a review of the literature, commentary, and comparison with oral leukoplakia

Laryngeal keratosis (LK) is a precancerous mucosal change with great similarity to oral leukoplakia. Its malignant transformation rate varies from 1% to 40%, with the highest rates being found in patients microscopically diagnosed as "keratosis with atypia" (KWA). Recent evidence indicates that even cases with only mild or moderate epithelial dysplasias are at increased risk for malignant transformation, with the highest rates occurring in patients with more severe dysplasia or carcinoma in situ. Approximately 81% of LK patients are men and the average age at diagnosis is 50 years, a decade younger than that for laryngeal carcinoma patients. A high proportion of LK patients are tobacco smokers (84%) and alcohol abusers (at least 35%). LK is almost always found on the true vocal cords and is usually bilateral (67%). Clinical signs of high risk include, in decreasing order of importance: erythroplakia, surface granularity, increased keratin thickness, increased size, recurrence after conservative removal, and long duration. The annual incidence of LK in the United States is 10.2 and 2.1 lesions per 100,000 males and females, respectively.