Laryngeal papillomatosis: correlation between severity of disease and presence of HPV 6 and 11 detected by in situ DNA hybridisation

Laryngeal Cancer in Patients Younger than 30 Years: A Review of 99 Cases

Laryngeal cancer in patients younger than 30 years is uncommon. We present data on this population obtained from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program. We identified 99 patients in this age group from the SEER 17 registry, which includes data submitted from 1973 through 2003. This population was made up of 52 females and 47 males; most were white, and most were aged 25 to 29 years. Malignancies of the glottis were the most common cancers, followed by supraglottic lesions. The 5-year relative survival rate was lowest among those aged 15 to 19 years—60.1%; 5-year relative survival among those aged 20 to 24 and 25 to 29 years was 87.7 and 87.4%, respectively. The etiology of squamous cell carcinoma (SCC) in children and adolescents remains uncertain, but in the adult population, a history of smoking, drinking, and poor oral hygiene cannot be ignored. Carcinoma of the larynx in young people has been related to malignant degeneration of papillomas and to complications of radiotherapy for papillomas. Infection with the human immunodeficiency virus possibly accelerates the development of SCC in patients with significant risk factors, presumably by impairing normal immune surveillance mechanisms.

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

Papilomatose laríngea recorrente: experiência de 10 anos

INTRODUÇÃO: Os papilomas de vias respiratórias são tumores benignos, de caráter recorrente e progressivo, induzidos por vírus. Sua etiologia está relacionada com infecções por papilloma virus humano, sendo descritas duas formas clínicas: juvenil e adulta. OBJETIVO: Comparar as duas formas de apresentação, juvenil e adulta, observando se há diferenças epidemiológicas ou clínicas entre elas. DESENHO DO ESTUDO: Coorte histórica. MATERIAL E MÉTODO: Realizou-se estudo dos pacientes atendidos na Clínica Otorrinolaringológica do HC-FMUSP com diagnóstico de papilomatose laríngea entre 1990 e 1999. Cinqüenta e um pacientes foram identificados, mas sete não confirmaram o diagnóstico. Assim, 44 indivíduos foram a base desta revisão, sendo 47,72% da forma juvenil e 52,27% da forma adulta. RESULTADOS: Não houve predomínio entre os sexos (p=0,98). A idade média de início dos sintomas foi de 5,3 anos na forma juvenil e 42,6 anos na forma adulta. A dispnéia foi mais prevalente na forma juvenil (p=0,03). A taxa de recidiva geral foi de 66%, sendo de 76,2% na forma juvenil e 56,5% na forma adulta (p=0,17). A incidência de recidiva precoce (<3 meses) foi maior na forma juvenil (p<0,001). Observamos 13% de transformação maligna na forma adulta da doença. CONCLUSÕES: Na forma juvenil, ocorreram recidivas precoces associadas a quadros de dispnéia, necessitando de múltiplas intervenções. Na forma adulta, também observamos alta taxa de recidivas, com índice elevado de transformação maligna. Tratamentos que aumentem o tempo entre as recidivas se fazem necessários nas duas formas de apresentação da doença.

[Advances in the diagnosis of ENT tumors in childhood]

In the present study we review ENT tumor pathology in childhood. Only the most salient aspects are emphasized and the variety of entities reviewed was restricted. Molecular biology techniques reveal infection by human papilloma virus (types 6 and 11) in 50 % of papillomas, while immunohistochemical techniques are less effective in papilloma virus detection. The myofibroblastic nature of nasal angiofibroma has been demonstrated and its incidence is 25 times more frequent in patients with familial polyposis of the colon. Overexpression of p53 occurs in the initial stages of nasopharyngeal carcinoma, while overexpression of c-myc is correlated with an unfavorable prognosis. Recently, olfactory neuroblastoma has been shown not to express the protein product of the MIC-2 gene (antibody 12E7), thus the hypothesis that it could be a member of the Ewing tumor family (neuroectodermal peripheral tumors) has not been confirmed, although it is a primitive neural tumor. The head and neck rhabdomyosarcoma with the best prognosis is that located in the orbit, and cytogenetic studies have shown chromosomic translocation t(2;13) in 50 % of these childhood tumors when they are of the alveolar-type, while trisomy of chromosome 2 or 20 is more characteristic of the embryonic-type. Currently, any classifying features of ENT lymphomas must be based on the Revised European-American Classification of Lymphoid Neoplasms (REAL). Papillary and medullary carcinomas are the most common histological types of thyroid carcinoma in childhood. Alterations in ret/PTC play a significant role in the pathogenesis of both.

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.

Tracheobronchial extension of recurrent respiratory papillomatosis

Endobronchial and pulmonary dissemination reportedly occurs in 5% of patients with laryngeal papillomatosis. It is more frequently observed in the juvenile form, and carries significant implications for treatment. In this study, we review our experiences with pulmonary and endobronchial extension of laryngeal papillomatosis. The records of the 52 patients with laryngeal papillomas treated at our institution since 1980 were reviewed. Twenty-nine percent of the patients (N = 15) developed tracheobronchial extension; 7% (N = 4) demonstrated pulmonary involvement. The birth history, race, sex, age at onset of symptoms, presenting symptoms, site and type of papillomas, surgical procedures, other methods of treatment, complications, and mortality data were analyzed. Eighty percent of the patients with tracheobronchial involvement were born to mothers with a positive history of vaginal condylomas. Pulmonary changes in 4 patients were observed on either chest radiographs or computed tomography and were manifested as multiple parenchymal nodules in 3 of the 4 patients. Pneumatoceles, cavitary empyema, and multiple recurrent pneumonias were the predominant complications of pulmonary involvement. Of the 15 patients with tracheobronchial extension, 80% (N = 12) required tracheotomy before their presentation to us. The number of multiple surgical procedures performed to remove papillomas ranged from 7 procedures in 1 patient with a solitary tracheobronchial lesion to more than 100 procedures in 2 patients with diffuse bronchopulmonary papillomatosis. As our study shows, tracheobronchial involvement continues to complicate surgical treatment in this challenging disease process.

Human papillomavirus type, proliferative activity, and p53: potential markers of aggressive papillomatosis

CONTEXT

The predictive value of nuclear proliferation antigen (Ki-67), tumor suppressor gene product p53, and human papillomavirus type has not been evaluated for outcome of laryngeal papilloma.

OBJECTIVE

This study was designed to determine whether immunohistochemical analysis of Ki-67 and p53 and human papillomavirus typing by polymerase chain reaction are able to identify patients with a more aggressive course of laryngeal papillomatosis.

DESIGN

Immunohistochemistry and polymerase chain reaction were performed on archival, paraffin-embedded, laryngeal papillomatosis biopsy specimens at the time of diagnosis, at an intermediate time during treatment, and at the last procedure available. Staining indexes for Ki-67 and p53 were determined, and human papillomavirus type was analyzed for all biopsies.

PATIENTS

Twelve patients with recurrent laryngeal papillomatosis for at least 5 years were selected from patients treated at our institution during the last 20 years.

MAIN OUTCOME MEASURES

Separate analyses were conducted comparing average Ki-67 and p53 indexes against disease outcome, viral type, or average number of procedures per year. Associations were analyzed between virus type, average number of procedures per year, outcome, and histology.

RESULTS

No statistically significant associations were noted in Ki-67 or p53 indexes and outcome. Weak associations were noted for p53 indexes and procedures per year and virus type. Weak associations also were noted between virus type and development of neoplasia.

CONCLUSIONS

Our observations suggest that human papillomavirus typing may be helpful in identifying patients with aggressive recurrent laryngeal papillomatosis. The weak association between p53 indexes and procedures per year and virus type may have some predictive value in identifying aggressive lesions.

Survey of sinonasal inverted papillomata for Epstein-Barr virus

BACKGROUND

Several studies have indicated an etiologic role for viruses in the development of sinonasal inverted papillomata (IP). A recent report demonstrates a strong relationship (65%) between Epstein-Barr virus (EBV) and these lesions using polymerase chain reaction (PCR) analysis.

METHODS

The present study analyzes a series of paraffin-embedded tissues, comprising 25 surgically resected IPs and four fungiform papillomata (FP) for the presence of EBV using a sensitive in situ hybridization (ISH) assay and PCR.

RESULTS

None of the specimens examined showed evidence of EBV infection by ISH, and only two papillomata (one sinonasal IP and one FP) gave positive reactions for EBV using PCR.

CONCLUSIONS

These data challenge the previous report and suggest that EBV is not a significant etiopathologic factor to be considered in the development of sinonasal IP.

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.

Detection of human papillomavirus in routinely processed biopsy specimens from laryngeal papillomas: evaluation of reproducibility of polymerase chain reaction and DNA in situ hybridization procedures

The frequency of human papillomavirus (HPV) in laryngeal papillomas varies largely among different studies. DNA in situ hybridization (ISH) has been the most widely used method for detection of HPV. The aim of this study was to compare the reproducibility and sensitivity of ISH with polymerase chain reaction (PCR) in 35 specimens of laryngeal papillomas routinely fixed in buffered or unbuffered formalin. Out of 12 specimens fixed in buffered formalin, 10 were positive for HPV 6/11 using ISH. The procedure was repeated three times and three specimens were positive only twice. Nine biopsies were positive for HPV using PCR with consensus primers (My 09/11) on dewaxed tissue without extracting DNA. In three repeated PCRs, the results were inconsistent in three samples. After DNA extraction, all 12 samples were positive with PCR. Of the 23 specimens fixed in unbuffered formalin, 14 were HPV-positive with ISH, while only one was positive with PCR. We concluded that PCR with My 09/11 consensus primers is a highly sensitive method for detection of HPV in laryngeal papillomas fixed in buffered formalin, but useless for samples fixed in unbuffered formalin. When DNA was extracted from the former type of fixed tissue, the results were highly reproducible. In contrast to PCR, ISH appeared to be less influenced by fixation procedure, but it was not as reproducible and sensitive as PCR. Negative results did not necessarily mean absence of HPV.

Ultrastructure and human papillomavirus DNA in papillomatosis of external auditory canal

BACKGROUND

A viral etiology has been suspected in papillomatosis of the external auditory canal (PEAC), but virus particles have not been detected so far, although they are easily demonstrable in skin warts. The purpose of the study was to solve this discrepancy by the use of polymerase chain reaction (PCR).

MATERIALS AND METHODS

Specimens from the external auditory canal of 14 patients with PEAC, but no human papilloma virus infection of the genital areas, were examined histologically by light and electron microscopy, as well as by PCR to detect viral DNA.

RESULTS

Histologically, papillomatosis was present in all specimens. Vacuolated cells were found in the upper part of the stratum malpighii in five cases. On electron microscopy, the numbers of perichromatin and interchromatin granules were increased, but no viral granules were observed. In all specimens, DNA of HPV 6 was detected using PCR, but there was no evidence of DNA of other HPV.

CONCLUSIONS

Papilloma of the external auditory canal is produced by infection with HPV 6.

Papova viruses and recurrent laryngeal papillomatosis

The pathogenesis of larynx papillomas has been a challenge of medical science for a long time. Both clinical observations and electronmicroscopical examinations have made it possible to establish the viral origin. Final evidence, however, has been achieved only by complicated immunohistochemical investigations. The Papova viruses--types 6 and/or 11--can be detected with in situ hybridization polymerase chain reaction amplification. HPV can be positivity demonstrated not only from visible papillomas but--in significant percentage--in neighboring healthy-looking mucous membranes. It may reveal the inadequacies of removal of lesions and the need for adjuvant therapy. To make treatment more effective we have developed a therapeutic regimen that combines CO2 laser microsurgery with immunostimulants.

Recurrent respiratory papillomatosis in the larynx: re-emergence of clinical disease following surgery

The treatment and aetiology of recurrent respiratory papillomatosis remains unclear. We report a case of laryngeal papillomatosis where repeated suction diathermy and later laser treatment led to the formation of a substantial glottic web, but a clinically papilloma-free state of the upper aerodigestive system. Division of the web led to widespread recurrence of the papillomas, which eventually resolved after the larynx had healed with the reformation of a limited anterior web. The role of surgical trauma and its effect on re-emergence of papillomas is discussed.

Laryngeal papillomatosis: molecular, histopathological, and clinical evaluation

Molecular, histopathological, and clinical studies were carried out on a series of 79 laryngeal papillomas (LP) from 36 patients in order to investigate the hypothesis that juvenile and adult LP may represent a biological entity causally related to Human papilloma virus (HPV) infection. Using in situ hybridization with biotin-labelled probes and polymerase chain reaction, we detected human papilloma virus (HPV) 6/11 in 28 of 29 juvenile LP, in 26 of 30 adult multiple, and in 17 of 20 adult solitary LP. None of LP was found to harbour HPV types 16, 18, 31, 33, and 51. There were no clear-cut histological differences between juvenile and adult LP, the presence of koilocytosis was equally observed in both, and there was no prevalent type of epithelial hyperplasia in either form, except that all three cases of atypical hyperplasias (precancerous lesions) were found among adult patients. During a 14 year follow-up, no carcinomatous transformation of LP was observed. All juvenile LP in our study had frequent recurrences of the disease, however, numerous surgical procedures were also required in 16 of 27 adult patients. Our study supports Lindeberg's hypothesis of a similar pathogenesis for all forms of LP caused by the HPV types 6/11.

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.

Ribavirin treatment for juvenile respiratory papillomatosis

Juvenile respiratory papillomatosis involving the tracheo-bronchial tree imposes a significant management problem and is sometimes life threatening. The mainstay of treatment is repeated vapourization with a CO2 laser. To date, adjunctive medical treatments have been of limited value. A tracheostomized child with extensive laryngo-tracheo-bronchial papillomatosis who has required bronchoscopic lasering at two-weekly intervals for three years was treated with ribavirin, a broad spectrum anti-viral agent. The drug was administered in nebulized form using a small particle aerosol generator (S.P.A.G.) to the lower respiratory tract (6 gm/150 ml over nine hours) on three consecutive nights every two weeks over seven weeks and also administered orally (15 mg/kg/day). Endoscopic assessments were made every two weeks. At 14 days the papillomata were regressing and far less lasering was required. No further lasering was required up to 56 days. One month after stopping the ribavirin, however, a few sessile papillomata in the tracheo-bronchial tree had recurred and were treated with the laser. No adverse reactions were encountered. During the treatment period there was a significant reduction in the frequency of therapeutic endoscopies. This promising response requires further evaluation to define the role of ribavirin in the treatment of juvenile respiratory papillomatosis.

Investigation of premalignant lesions of larynx epithelium with histoautoradiography and HPV-assay

The histological evaluation of precancerous alterations of larynx epithelium is, in transitional cases, very difficult. The differentiation of harmless metaplasia, hyperplasia and keratosis from abnormal proliferation depends on the pathologist's training and experience. Fine diagnostic lines separate the different grades of dysplastic epithelial alterations. The tritiated thymidine, 3H-TdR, labelling and histoautoradiographic procedure of biopsy specimens taken from the larynx provide the possibility to recognise the DNA synthetiser cells. The number, location and distribution of 3H-TdR labelled cells in the epithelial layers help us to distinguish with clarity the growth activity, the degree of dysplasia. After 3 weeks' exposition time of sections prepared by photoemulsion and stained with haematoxilin-eosin, the result can be assessed. In addition to histoautoradiography HPV-assay was applied, as HPV may play a role in the pathogenesis of laryngeal preneoplastic alterations.

Juvenile respiratory papillomatosis: acyclovir reassessed

Four patients with aggressive respiratory papillomatosis have been treated with oral Acyclovir as adjuvant therapy while continuing to undergo regular endoscopy and laser treatment to the lesions. The duration of Acyclovir administration ranged from 2 weeks to 3 months. Two patients had papillomatosis confined to the larynx and two in addition had disease in the lower respiratory tract. One of the four patients had less aggressive disease during the treatment period. Acyclovir does not appear to significantly influence respiratory papillomatosis. Acyclovir's activity is dependent upon the presence of virally encoded thymidine kinase. This enzyme is not known to be encoded by papilloma viruses. Acyclovir is not recommended in the treatment of juvenile respiratory papillomatosis.

Influence of fixation on human papillomavirus DNA detection in frozen and embedded paraffin lesions by in situ hybridization with biotinylated probes

Series of frozen or paraffin-embedded tissues from various body sites, taken from non-immunosuppressed or immunosuppressed patients with persistent papilloma lesions were examined for the presence of group specific antigen from human papillomavirus (HPV) by indirect immunofluorescence or HPV DNA by in situ hybridization with biotinylated probes. We have shown that it is possible to detect HPV DNA after fixation of tissues in neutral formalin, Bouin's or Baker's solution. However, the sensitivity was reduced as compared to frozen tissues. The HPV DNA was detected in nuclei of heavily infected epithelial cells such as plantar or hand warts or in dispersed cells containing high copy numbers of HPV DNA from lesions such as squamous cell carcinomas or keratoacanthomas. In premalignant or malignant lesions of both immunosuppressed or non-immunosuppressed patients, HPV DNA was rarely detected after fixation. HPV types commonly described for skin and genital samples were identified in non-immunosuppressed patients, whereas in transplant recipients oncogenic HPV type 16 was identified in benign warts as well as in premalignant or malignant lesions. Positive reactions with several HPV types were more frequent in lesions from grafted patients than from the normal population. Virus antigen was detectable more frequently in frozen sections than in fixed tissues. Our findings indicate that in situ hybridization is an appropriate and rapid technique to study the presence of HPV infection. However, numerous controls are needed to avoid misinterpretations.

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.

Human papillomavirus 6, 11, and 16 in laryngeal papillomas

Twenty-seven cases of benign laryngeal papillomas, both single and multiple variants, were analysed for human papillomavirus (HPV) by DNA slot-blot hybridization chiefly to determine the pattern of infection in Hong Kong Chinese. DNA was extracted from paraffin blocks of formalin-fixed tissue and probed separately for HPV 6, 11, 16, and 18. Sixteen cases (59 per cent) showed the presence of at least one of these four HPV genomes. Thirteen cases (48 per cent) were positive for HPV 11 only. Three other cases (11 per cent) showed triple positivity for HPV 6, 11, and 16. None were positive for HPV 18. The predominance of HPV 11 infection contrasts with other series which have shown either an almost equal distribution of HPV 6 and 11 or a predominance of HPV 6. The finding of HPV 16 in three cases was unexpected. Using the polymerase chain reaction (PCR) with primers complementary to the upstream regulatory region of the HPV 16 viral DNA, the presence of HPV 16 genome was confirmed in all three cases. As the number of HPV 16-positive cases in this study is small, analysis of more cases using fresh biopsy material and a wider range of HPV type-specific PCR primers is warranted to determine the relative incidence of HPV subtypes in these benign laryngeal papillomas.

Sinonasal papillomas and human papillomavirus: human papillomavirus 11 detected in fungiform Schneiderian papillomas by in situ hybridization and the polymerase chain reaction

A series of 19 paraffin-embedded sinonasal papillomas (four squamous papillomas, three fungiform papillomas, nine inverted papillomas, and three cylindrical cell papillomas) were investigated for evidence of human papillomavirus (HPV) infection using immunohistochemistry (polyclonal antibody to HPV capsid antigen), in situ hybridization (DNA probes for HPV 6/11, 16/18, and 31/33/35), and the polymerase chain reaction (primers and probes for HPV 6, 11, 16, 18, and 33). All three fungiform papillomas were positive by all three techniques: immunohistochemistry, in situ hybridization for HPV 6/11, and the polymerase chain reaction for HPV 11. None of the other lesions contained detectable HPV using the specific probes included in this study. These results support the continued classification of fungiform papilloma as a distinctive variant of schneiderian papilloma characterized by a predominantly exophytic growth pattern and an association with HPV 11.

Comparative in situ hybridisation study of juvenile laryngeal papillomatosis in Papua New Guinea and Australia

A comparative study of cases of juvenile laryngeal papillomatosis from Papua New Guinea (n = 3) and Brisbane, Australia (n = 9) was carried out. In situ hybridisation reactions for human papillomavirus (HPV) types 6 and 11 occurred in 11 cases. All three cases from Papua New Guinea and eight from Australia gave positive signals. A negative reaction was observed in one Australian case. The intensity of the reaction was strong in seven cases, moderate in one, and weak in three. An equivocal reaction was also noted with probes for types 16 and 18, and types 31, 33, and 35 in two cases from Australia and one from Papua New Guinea. It is concluded that as similar staining patterns and intensities occurred in cases from both areas, the aetiology is the same. The equivocal reactions noted in three cases were probably due to cross hybridisation rather than multiple infection.