Demonstration of human papillomavirus types 6 and 11 in juvenile laryngeal papillomatosis by in-situ DNA hybridization

[Recurrent laryngeal papillomatosis]

Human papillomaviruses (HPV) 6 and 11 cause 90% of recurrent laryngeal papillomatosis (RLP). It is unclear whether recurrences are caused by new infections or the spread of infected cells. Symptomatic and sometimes curative treatment is laser surgery or conventional microsurgical removal. RLP surgery aims to relieve shortness of breath and improve the voice. Patients (especially children) are affected by voice problems, repetitive surgeries, pulmonary manifestations, and psychological trauma. Vaccination with Gardasil 9 (Merck & Co., Rahway, NJ, USA) prevents new infections with HPV 6, 11, 16, 18, 31, 33, 45, 52, and 58 and induces vaccine antigen-specific antibodies and CD4+ T helper cells. According to current studies, RLP can be avoided with prophylactic vaccination. The treatment is associated with a general vaccination risk (European Medicines Agency approval: girls and boys from 9 years). Studies also show that the vaccine after removal of HPV-associated neoplasia/papilloma prevents recurrences. Extension of the vaccination recommendation to prevent recurrences of HPV-associated diseases in men may promote applicability and herd immunity. For rare and treatment-refractory cases with laryngotracheal involvement, systemic therapy with bevacizumab (e.g. Avastin; Genentech, San Francisco, CA, USA), a VEGF antibody, is a promising adjuvant treatment option.

Human Fibroblast Interferon Adjuvant to CO2 Laser in the Treatment of Recurrent Juvenile Laryngeal Papillomatosis: Experience with 7 Cases

Preliminary results of adjuvant human fibroblasts interferon (IFN beta) given after CO2 laser excision in recurrent laryngeal papillomatosis in 7 adult patients are reported. Diagnostic procedure included histologic and immunohistochemical investigations to demonstrate the presence of viral cytopathic effect and for characterization of the virus. All patients underwent CO2 laser excision under general anesthesia followed by administration of IFN beta intramuscularly at the dose of 4x106 IU/day for 10 consecutive days. In the presence of complete remission, patients were followed without further therapy; in the presence of partial remission, a new combined treatment was established. All patients had a complete remission after combined treatment, but 4 subsequently developed recurrences. Treatments were always well tolerated; even cirrhotic patients showed no side effects.

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.

Diagnostic challenges of laryngeal papillomatosis and its implications among children in developing country

OBJECTIVES

To create an awareness of laryngeal papillomatosis in children and the implications of its mismanagement among the general practitioner and paediatricians, and to offer suggestions on its diagnostic techniques.

METHOD

Medical records of children with histologically confirmed laryngeal papillomatosis managed at the Otorhinolaryngology department of University College Hospital Ibadan Nigeria through 1993-2007 were reviewed for essential clinical data.

RESULTS

There were 38 paediatric patients, 23 (60.53%) males and 15 (39.47%) females, with laryngeal papillomatosis. Only 2 (5.26%) of these patients were correctly diagnosed by the referring clinicians. Diagnosis was delayed for 5 weeks to 3 months. About 90% of these patients had emergency tracheostomy and 92% had surgical excision for 2 sections or less.

CONCLUSION

Laryngeal papillomatosis misdiagnosis and mismanagement were common in our environment due to clinicians not being conversant with the disease entity. It should therefore be considered an important differential diagnosis in children with laryngeal symptoms to improve its clinical outcome. Otorhinolaryngologists should always be involved early without delay in the management.

Effect of human papilloma virus expression on clinical course of laryngeal papilloma

CONCLUSION

Our observations suggest that human papilloma virus (HPV) 6/11 is the main causative agent of laryngeal papilloma and that detection of active HPV DNA expression may be helpful in identifying patients with aggressive recurrent laryngeal papilloma.

OBJECTIVES

HPV is assumed to be the main causative agent of this disease. We investigated the expression of the entire genotype of HPV in cases of laryngeal papilloma and correlated their expression with the clinical course of the disease.

SUBJECTS AND METHODS

Seventy cases of laryngeal papilloma were evaluated for the presence of the HPV genome by in situ hybridization (ISH) using wide-spectrum HPV DNA probe. Specific types of HPV infection were determined by DNA ISH using type-specific HPV DNA probes (HPV 6, 11, 16, 18, 31, 33). Separate analyses were conducted comparing viral types, frequency of recurrences and duration of disease-free periods.

RESULTS

We detected HPV DNA in 40 of the 70 laryngeal papilloma cases (57%). In particular, HPV DNA was detected in 75% of the juvenile types. There were significant associations between HPV and laryngeal papilloma (p<0.01). Among the HPV-positive cases, major specific types were HPV 6/11 (97%). Significant associations were also noted between viral expression and clinical course.

Juvenile recurrent respiratory papillomatosis: still a mystery disease with difficult management

Juvenile recurrent respiratory papillomatosis (RRP) is the most common benign neoplastic disease of the larynx in children and adolescents and has a significant impact on patients and the health care system with a cost ranging from $60,000 to $470,000 per patient. The aim of this paper is to review the current literature on RRP and summarize the recent advances. RRP is caused by human papillomavirus (HPV; mainly by types 6 and 11). Patients suffer from wart-like growths in the aerodigestive tract. The course of the disease is unpredictable. Although spontaneous remission is possible, pulmonary spread and malignant transformation have been reported. Surgical excision, including new methods like the microdebrider, aims to secure an adequate airway and improve and maintain an acceptable voice. Repeated recurrences are common and thus overenthusiastic attempts to eradicate the disease may cause serious complications. When papillomas recur, old and new adjuvant methods may be tried. In addition, recent advances in immune system research may allow us to improve our treatment modalities and prevention strategies. A new vaccine is under trial to prevent HPV infection in women; the strongest risk factor for juvenile RRP is a maternal history of genital warts (transmitted from mother to child during delivery). Better understanding of the etiology of the disease and the knowledge of all available therapies is crucial for the best management of the affected patients.

Papillary endobronchial squamous cell carcinoma

A case of papillary endobronchial squamous cell carcinoma incidentally discovered on routine imaging studies is described. The patient, a 75-year-old woman, underwent imaging studies as part of a standard evaluation for a fracture on the right side of the hip. Chest radiographs were unremarkable other than for a nodular opacity overlying the left hemidiaphragm. Computed tomography of the chest, however, demonstrated an elongated, irregular mass in the right lower lobe that appeared to be associated with an adjacent segmental right lower lobe bronchus. Endoscopy followed by surgical resection was undertaken, revealing a tan, soft mass measuring 1.5 x 1.3 x 0.8 cm that was confined to the bronchus and did not appear to extend into the surrounding lung parenchyma. Microscopically, the mass showed a papillary, superficial squamous cell carcinoma confined to the bronchial mucosa without invasion of adjacent structures. The pathological and imaging features of this unusual variant of bronchogenic carcinoma are reviewed as well as the radiological differential diagnosis of endobronchial lesions. To our knowledge, this is the first report that describes the computed tomographic features of this rare lesion.

HspE7 treatment of pediatric recurrent respiratory papillomatosis: final results of an open-label trial

OBJECTIVES

We sought to evaluate the effectiveness of HspE7, a recombinant fusion protein of Hsp65 from Mycobacterium bovis BCG and E7 protein from human papillomavirus 16, to improve the clinical course of pediatric patients with recurrent respiratory papillomatosis.

METHODS

An open-label, single-arm intervention study was conducted in 8 university-affiliated medical centers. Twenty-seven male and female patients with recurrent respiratory papillomatosis, ages 2 to 18 years, were enrolled and followed up to 60 weeks. Before enrollment, these patients required surgery on average every 55 days. After a baseline debulking surgery, the patients received HspE7 500 microg subcutaneously monthly, for 3 doses over 60 days. The primary end point was the length of the interval from the last surgery during the treatment period until the first debulking surgery in the posttreatment period, compared with the median intersurgical interval (ISI) of the 4 surgeries before the treatment.

RESULTS

The mean of the first posttreatment ISI increased 93% (from 55 days to 106 days; p < .02). The median ISI for all surgeries after treatment was similarly prolonged (mean, 107 days; p < .02), indicating a sustained treatment effect, and was associated with a significant decrease in the number of required surgeries (p < .003). Unexpectedly, the treatment effect was most striking in the 13 female patients, who had statistically significant increases in both the first posttreatment ISI (142%; p < .03) and the median ISI (147%; p < .03). The most common adverse events were mild-to-moderate injection site reactions.

CONCLUSIONS

Treatment with HspE7 appears to significantly improve the clinical course in pediatric patients with RRP insofar as it reduces the frequency of required surgeries. These results warrant a confirmatory phase III trial.

Efficacy of cidofovir injection for the treatment of recurrent respiratory papillomatosis

To evaluate the efficacy of intralesional cidofovir injection for the treatment of recurrent respiratory papillomatosis (RRP). It is a prospective, open-label study design. This prospective study included 16 RRP patients, ages 9 to 68 years, who were treated with intralesional injections of cidofovir combined with surgical excision of RRP. The disease states of the patients pretreatment and posttreatment were assessed by assigning RRP severity scores, examining the need for any surgical excision of RRP, and evaluating the presence of RRP upon long-term follow-up. Sixteen patients were treated with cidofovir; however, three were lost to follow-up. Thirteen patients are the subjects of this report. This study group included three pediatric patients. Ten of thirteen patients (76.9%) responded to the treatment and are presently in remission. One patient did not respond, and two patients relapsed after initial success or had a partial response. The responders consisted of eight adults and two children. The mean number of injections the responders received was 3.5, and the average follow-up period of the responders was 25.4 months. No immediate complication of cidofovir treatment was evident. However, three patients were found to have significant vocal fold scarring after long-term follow-up. Cidofovir has been found to be efficacious in treating RRP. Further study regarding long-term follow-up and the assessment of possible side effects after cidofovir intralesional injection for RRP is required.

Indole-3-carbinol for recurrent respiratory papillomatosis: long-term results

We report the results of a clinical study using Indole-3-Carbinol (I3C) for the treatment of recurrent respiratory papillomatosis (RRP). I3C is abundant in cruciferous vegetables and has been shown to decrease papillomatous growth in cell cultures and be effective in an animal model of RRP. This is a prospective, open-label study design. Patients with RRP were enrolled from September 1996 to August 2001 and treated with I3C (adult dose of 200 mg PO BID). All patients underwent complete surgical removal and then started I3C. Further surgery was performed on an as-needed basis. Patients were categorized as having a complete, partial, or no response to I3C. Thirty-three patients treated with I3C were available for long-term follow-up (mean=4.8 years), whereas 12 patients were lost to follow-up. Eleven (33%) patients experienced remission of papillomatous growth and did not require surgery while on I3C. Ten (30%) patients had a reduction in papillomatous growth that resulted in less frequent surgery. Twelve patients (36%) had no clinical response. No patients experienced a worsening of their RRP. Of the 9 pediatric patients available, 1 experienced a complete response, 3 a partial response, and 5 had no response to I3C. Twelve patients with a positive response (partial or complete) to I3C are still taking I3C. Seven positive responders discontinued I3C, 3 of which have remained disease-free, whereas 4 continue to have RRP. No immediate or long-term side effects related to I3C were found. I3C has been found to be a successful treatment option for RRP. I3C's efficacy in pediatric patients merits further study.

Acquired upper airway obstruction

Acquired upper airway obstruction is a common cause of respiratory emergencies in children. Most pathologic processes that result in upper airway compromise are a consequence of infection, trauma or aspiration. Today, many of the infectious causes of upper airway obstruction have lost their threat as a result of the progress made in preventing and treating these infections. Prompt recognition and appropriate management of the child presenting with upper airway obstruction remains critical, because certain causes can progress rapidly from a mild to a potentially life-threatening disease state. A correct diagnosis can often be made by history and physical examination, but additional studies may be useful in selected cases. The child's clinical appearance is the most reliable indicator of severity, and measurable signs are of less value. If respiratory failure is imminent, airway protection and endoscopy for definitive diagnosis may have priority over any other therapeutic or diagnostic procedure.

Human Papillomavirus Vaccines and Prevention of Cervical Cancer

Cervical cancer and precancerous cervical lesions constitute a major problem in women's health. Every year 470,000 cases of cervical cancer are diagnosed worldwide, and about half the women afflicted will die. In the United States alone, approximately 14,000 cases of cervical cancer are diagnosed each year despite the availability of screening and access to high-quality gynecological care. With the confirmation that cervical cancer is caused by an infectious agent, human papillomavirus, the possibility of fighting this disease with either prophylactic or therapeutic vaccination arose. This review describes advances in vaccine development and very promising first results for prophylactic vaccination against cervical cancer.

HLA class II polymorphisms and susceptibility to recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is characterised by multiple laryngeal papillomas. Left untreated, the lesions enlarge, spread, and endanger the airway. Medical treatments are unsatisfactory, and repeated surgery remains the mainstay of therapy. RRP is caused by human papillomavirus (HPV) infection. However, since oral HPV infection is common and RRP is rare, other host and/or viral factors may contribute to pathogenesis. In an attempt to identify such factors, we have investigated 60 patients. The patients were HLA class I, II, and tumor necrosis factor TNF typed by sequence-specific primer PCR, and the results compared to those for 554 healthy controls by using Fisher's exact test. Peripheral blood mononuclear cell proliferative responses of 25 controls and 10 patients to HPV-11 L1 virus-like particles (VLP) were compared. Short-term VLP-specific T-cell lines were established, and recognition of L1 was analyzed. Finally, the L1 open reading frames of HPV isolates from four patients were sequenced. Susceptibility to RRP was associated with HLA DRB1*0301 (33 of 60 patients versus 136 of 554 controls, P < 0.0001). The three most severely affected patients were homozygous for this allele. A range of T-cell proliferative responses to HPV-11 VLP were observed in DRB1*0301-positive healthy donors which were comparable to those in DRB1*0301-negative controls. Individuals with juvenile-onset RRP also mounted a range of VLP responses, and their magnitude was negatively correlated with the clinical staging score (P = 0.012 by the Spearman rank correlation). DRB1*0301-positive patients who responded to L1 recognized the same epitope as did matched controls and produced similar cytokines. Sequencing of clinical isolates excluded the possibility that nonresponsiveness was the result of mutation(s) in L1.

External genital warts: diagnosis, treatment, and prevention

External genital warts (EGWs) are visible warts that occur in the perigenital and perianal regions. They are due primarily to non-oncogenic human papillomavirus (HPV) types, usually types 6 and 11. Physical examination assisted by bright light and magnification is the recommended approach for primary diagnosis. Biopsy is indicated when EGWs are fixed to underlying structures or discolored or when standard therapies are not effective. Recurrences are common, and there is no single treatment that is superior to others. Among women with atypical squamous cells, molecular HPV testing may be useful in determining who should be referred for colposcopy. Condoms may provide some protection against HPV-related diseases and thus are recommended in new sexual relationships and when partnerships are not mutually monogamous. Because the efficacy of cesarean section in preventing vertical transmission of HPV infection from women with EGWs to their progeny has not been proved, it is not recommended.

Pharmacotherapy of recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is a disease which affects both children (juvenile-onset RRP) and adults (adult-onset RRP). While a greater amount of information is known about the epidemiology of juvenile-onset than adult-onset RRP, fundamental work is still needed to more fully describe areas such as the mode of transmission. The primary management approach focuses on the removal of the papillomas by surgical debulking, although persistence of the human papillomavirus genome and subsequent recurrence of disease is the typical outcome. In a minority of patients, surgical management must be supplemented with adjuvant medical therapy, with IFN being the best studied and most commonly used. Other adjuvant treatments being employed include photodynamic therapy, indole-3-carbinol, ribavirin and cidofovir. Large controlled trials are lacking for all but IFN, making it extremely difficult to assess clinical benefit and risk in a systematic fashion at the current time. As with surgical management, viral persistence occurs following treatment with these adjuvant modalities, further contributing to the challenge of managing patients with this potentially devastating disease.

A new laser treatment for vocal cord papilloma--585-nm pulsed dye

OBJECTIVES

Microvascular targeting with the 585- nm pulsed dye laser (PDL) may provide a new form of therapy to control symptoms caused by recurrent respiratory papillomatosis (RRP).

METHODS

Ten patients with RRP underwent 13 procedures under general anesthesia with the 585-nm PDL. A micromanipulator (11 procedures) and a flexible nasolaryngoscope (2 procedures) were used to deliver the laser pulses. Patients were followed postoperatively according to protocol.

RESULTS

Clinical examination revealed regression of papillomas in all patients. Seven patients had complete regression after PDL surgery, and 2 patients had partial response to treatment. One patient was lost to follow-up. No complications were present during this prospective nonrandomized pilot study.

CONCLUSION

Patients treated with PDL experienced regression of their papillomas. PDL may provide patients with RRP with an alternative treatment without the risks associated with CO(2) laser surgery. This procedure also has potential to be delivered on an outpatient basis with flexible fiberoptic laryngoscopes.

Juvenile onset recurrent respiratory papillomatosis: possibilities for successful antiviral therapy

Recurrent respiratory papillomatosis (RRP) is a potentially devastating disease that can have significant morbidity, and can even result in mortality due to airway compromise or, less commonly, malignant transformation. Two distinct types of RRP exist: adult-onset RRP (AO-RRP) and juvenile-onset RRP (JO-RRP). Acquisition of human papillomavirus (HPV), the causative agent of RRP, is believed to occur in the peripartum period in the case of JO-RRP, with disease symptoms (primarily hoarseness) becoming apparent during the first several years of life. Treatment currently consists of surgical debulking of the papillomas to relieve airway obstruction. However, numerous antiviral therapies have also been evaluated, albeit primarily under uncontrolled settings. This article will review the biology, natural history and management of HPV infection, with particular emphasis on JO-RRP.

Preliminary results of the use of indole-3-carbinol for recurrent respiratory papillomatosis

OBJECTIVE

We report the preliminary results of a phase I trial using indole-3-carbinol for the treatment of recurrent respiratory papillomatosis. Indole-3-carbinol is a chemical that is found in high concentrations in cruciferous vegetables and has been shown to alter the growth pattern of recurrent respiratory papillomatosis cell cultures and to be effective in an in vivo animal model of recurrent respiratory papillomatosis.

METHODS

Eighteen patients were treated with oral indole-3-carbinol and had a minimum follow-up of 8 months and a mean follow-up of 14.6 months. All patients received indole-3-carbinol, and outcome measures included a change in papilloma growth rate and the need for surgery during treatment compared with before treatment. All patients had serial examinations with videoendoscopy to document papilloma location and growth rate.

RESULTS

Thirty-three percent (6 of 18) of the study patients had a cessation of their papilloma growth and have not required surgery since the start of the study. Six patients have had reduced papilloma growth rate, and 6 (33%) patients have shown no clinical response to indole-3-carbinol. Indole-3-carbinol affects the ratio of hydroxylation of estradiol; changes in the ratios of urinary 2-hydroxylation and 16-hydroxylation of estradiol caused by indole-3-carbinol correlated well with clinical response. No major complications or changes in the children's growth curve were noted.

CONCLUSIONS

The preliminary results of treating recurrent respiratory papillomatosis with indole-3-carbinol holds promise. Longer follow-up of this patient group and a blinded, controlled trial are required. We conclude that indole-3-carbinol appears to be safe and well tolerated and may be an efficacious treatment for recurrent respiratory papillomatosis.

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.

Clinical update on the role of HPV and cervical cancer

In the mid-1980s, a clear connection was made between infection by the human papillomavirus (HPV) and cervical cancer. This association led to the generation of a large body of literature about the diagnosis, testing, treatment, transmission and, virological life span of HPV-related neoplasms and cancers. Because of advances in virology, molecular biology, and biochemistry, more is known about HPV and its effects on cervical neoplasms than ever before. Because deaths from cervical cancer, while less common in the United States and western Europe, account for 20% of cancer deaths in women worldwide (1), accurate knowledge of the disease and its prevention is critical for nurses working with patients both with preinvasive and invasive disease.

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.

Detection of human papillomavirus in laryngeal lesions by in situ hybridization

Human papillomavirus (HPV) is associated with human neoplasms of squamous epithelium. Squamous papillomas and verrucous carcinomas are two types of squamous neoplasms of the larynx that present difficult problems in differential diagnosis. Using in situ hybridization with biotinylated DNA probes, we examined benign squamous papillomas and verrucous squamous carcinomas of the larynx for the presence of HPV. Forty-two biopsy specimens from 18 patients with laryngeal papillomas and 11 biopsy specimens from seven patients with verrucous carcinomas were obtained from the files of Pennsylvania Hospital, Philadelphia, PA. Tissue sections were hybridized with an HPV DNA cocktail. The HPV-positive cases then were subtyped further with DNA probes specific for HPV subtypes 6/11, 16/18, and 31/33/35. All benign squamous papillomas (42 of 42) were positive for HPV subtype 6/11. None of the verrucous carcinomas contained demonstrable HPV (none of 11). Some of the squamous papillomas were recurrences, which shows the persistence of the virus. These results indicate that laryngeal papillomas may be related to HPV, but verrucous carcinomas are not.

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.

Human papilloma viruses in the human hypopharynx

The possible association of human papilloma viruses (HPV) with laryngopharyngeal squamous cell carcinoma is under investigation. Recent work suggests regional differences in the prevalence of HPV infection in the hypopharynx. The present study investigates the prevalence of HPV in tissue obtained from a series of piriform fossae. Piriform fossa epithelium was harvested from 12 autopsy cases free of local disease. DNA was obtained by SDS/Proteinase K digestion. Evidence of HPV infection was documented by the polymerase chain reaction using oligonucleotide primers complementary to sequences in the E6 region of HPV types 11, 16 and 18. All the specimens were positive for beta-globin. HPV11 was isolated from two patients. None were positive for HPV16 or HPV18. An 18% prevalence rate for HPV11 in the normal human hypopharynx was found.

Human papilloma viruses: a study of their prevalence in the normal larynx

The association of human papilloma viruses (HPV) with laryngopharyngeal squamous cell carcinoma is under investigation. The suitability of control tissue in the reported series, invariably obtained from histologically normal tissue adjacent to a squamous cell carcinoma or from patients with benign laryngopharyngeal disease, is questionable. The present study determined the prevalence of HPV in a series of normal larynges. Twelve autopsy larynges were collected. DNA was obtained by SDS proteinase K digestion. Evidence of HPV infection was documented by the polymerase chain reaction using oligonucleotide primers complementary to sequences in the E6 region of HPV types 11, 16 and 18. Four female and eight male larynges, mean age 65 years (SD = 16 years) were collected 72 hours postmortem (median value). HPV type 11 was isolated from three specimens. A 25 per cent prevalence rate for HPV 11 was found. No other HPV types were isolated.

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.

Elevated levels of the p53 tumour suppressor protein in the basal layer of recurrent laryngeal papillomas

Using immunocytochemical techniques, recurrent laryngeal papillomas from six adult patients were studied. The p53 tumour suppressor gene protein was detected in the basal epithelial cells in papillomas from all six patients. None was detected in normal epithelium. Elevated levels of p53 protein are usually indicative of its inactivation either by point mutation or by complexing with tumour virus proteins.

Detection of human papillomavirus infection in diseased and nondiseased sites of the respiratory tract in recurrent respiratory papillomatosis patients by DNA hybridization

We examined 12 recurrent respiratory papillomatosis patients, who were undergoing treatment for recurrence of their disease, for the presence of human papillomavirus (HPV). Biopsies were obtained from their respiratory papillomas and nondiseased sites (NDS) of the respiratory tract: the nasopharynx, posterior tonsillar pillar, aryepiglottic fold, cervical trachea, intrathoracic trachea, and bronchi. The presence of HPV DNA was determined by using the ViraPap/ViraType DNA hybridization procedure. Two thirds of the patients were infected with HPV 6/11 in either the diseased papilloma or NDS: 50% of patients with papilloma specimens typed positive (6 of 12), and 40% of the patients typed HPV-positive in one or more biopsies from the NDS (4 of 10). No single NDS was more likely to be infected with HPV than any other. No oncogenic HPV types 16/18 or 31/33/35 were detected in the papillomas or NDS of these patients. Only patients with multiple, and not isolated, papilloma involvement were found to harbor HPV DNA in NDS; and 80% of those with infected NDS, compared to 20% of those without infected NDS, required a shorter (no more than 3 months) surgical treatment interval. Our results show that HPV infection frequently persists in adjacent, clinically normal sites, and suggest that the extent of NDS involvement may predict both the extent of disease and the likelihood of recurrence.

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.

Verrucous carcinoma of the leg positive for human papillomavirus DNA 11 and 18: a case report

Human papillomavirus (HPV) types 6 and/or 11 have been associated with benign lesions, while types 16, 18, 31, and 33 are prevalent in malignant lesions. This case report describes the findings in a verrucous carcinoma of the leg, which was examined for HPV types 11, 16, and 18 by in situ DNA hybridization. The lesion gave positive results for HPV subtypes 11 and 18, a combination that, to our knowledge, has not been previously reported in this neoplasm.

Laryngeal papillomatosis with human papillomavirus DNA contracted by a laser surgeon

A 44-year-old laser surgeon presented with laryngeal papillomatosis. In situ DNA hybridization of tissue from these tumors revealed human papillomavirus DNA types 6 and 11. Past history revealed that the surgeon had given laser therapy to patients with anogenital condylomas, which are known to harbor the same viral types. These findings suggest that the papillomas in our patient may have been caused by inhaled virus particles present in the laser plume.

In situ hybridisation in perspective

In the introduction to this review two questions were posed: is the technology associated with ISH ready for general use, and will the method become an important investigative tool? With the exception of the demonstration of some single and low copy sequences, non-radioactive ISH is now sufficiently developed and simplified to make it a routine technique. It is also clear that ISH will continue to have an important research role. In diagnostic pathology the technique is already providing valuable information and the present decade should see the development of many more diagnostic applications.

Human papillomavirus in oesophageal squamous cell carcinoma

Thirty seven cases of oesophageal squamous cell carcinoma were studied by applying DNA slot blot analysis and in situ hybridisation using type specific probes for HPV 6, 11, 16 and 18. Cases of condyloma accuminata, cervical carcinoma, and laryngeal papilloma were used as controls. Blocks including areas of invasive carcinoma, intraepithelial neoplasia, and normal epithelium were studied in each case. No HPV genome was detectable in any of the oesophageal cases. It is concluded that these types of HPV do not have an association with oesophageal squamous cell carcinoma.

An investigation into the role of human papillomavirus in endobronchial papillary squamous tumours

Tissue specimens from 15 patients with endobronchial papillary squamous tumours were probed for the presence of human papillomavirus DNA using the technique of in situ hybridization with probes to human papillomavirus genotypes 4, 5, 6b, 8, 11, 16 and 18. Despite the histological similarity of these lesions to known human papillomavirus-associated tumours no evidence of hybridization was detected in any of the cases analysed. It is thus unlikely that human papillomavirus has a significant role in the genesis of these tumours.

Discrimination of closely homologous HPV types by nonisotopic in situ hybridization: definition and derivation of tissue melting temperatures

It is generally assumed that nucleic acid association during in situ hybridization reactions is similar to that of nucleic acid association in solution. This assumption has been investigated by detecting closely homologous human papillomavirus types 6 and 11 by in situ hybridization as a model for the evaluation of stringency conditions in clinical biopsies. By examining matched and mismatched, labelled and target sequences under various stringency conditions, empirical DNA-DNA stability curves and their derivative equations for tissue melting temperatures (Tmt) were derived. The corresponding values for Tmt are 10-20 degrees C higher than their solution equivalents. These data, supported by polymerase chain reaction experiments, demonstrate that closely homologous viral DNAs cross linked in tissue by formaldehyde fixation do not interact with the corresponding labelled probes as predicted from solution kinetic equations. This not only has theoretical implications but is also relevant to the accuracy of clinical diagnostic testing.

The presence of human papillomavirus (HPV) in solitary adult laryngeal papillomas demonstrated by in-situ DNA hybridization with sulphonated probes

Human papilloma virus (HPV) types 6 and 11 have been repeatedly demonstrated in multiple laryngeal papillomas, and there is little doubt that these lesions are caused by HPV. It has been clearly demonstrated in recent reports that the clinical course of solitary adult onset laryngeal papillomas is entirely different from that of multiple papillomas of juvenile as well as of adult onset. We here report the presence of HPV types 6 and 11 in 19 out of 20 solitary papillomas from 16 patients, while HPV types 16 and 18 were totally absent. We conclude that the milder clinical course in such patients is most likely to be due to host factors, rather than to viral factors.

Immunohistochemical demonstration of human papilloma virus antigen in human colon neoplasms

The presence of human papilloma virus (HPV) has recently been demonstrated in colon tumors, but the incidence of HPV infection in normal colon mucosa or in benign or malignant neoplasms of the mucosa is unknown. We studied both neoplastic and normal human colon tissue for the presence of HPV antigen using immunohistochemical techniques. Ninety colon specimens were studied. Three consecutive series of normal colon mucosa (N = 30), single benign tubulovillous adenomas (N = 30), and invasive carcinomas (N = 30) were selected and confirmed histologically. Formalin-fixed paraffin-embedded samples of each tissue were prepared using immunohistochemical techniques and resultant slides were read blindly and graded simply as positive or negative for HPV antigen. The presence of HPV antigen varied dramatically between groups, with 97% of the invasive carcinomas, 60% of the benign tubulovillous adenomas, and 23% of the normal mucosa positive for HPV antigen. Groups were statistically significant using chi 2 analysis (P less than 0.001). We conclude that an association exists between the human colon neoplasia and the presence of HPV antigen. This may suggest an etiologic role of the virus in colon cancer.

Laryngeal papillomas: the epidemiology in a Danish subpopulation 1965-1984

The incidence rate of laryngeal papillomas in a Danish subpopulation (approximately 2.8 million inhabitants) was 3.84 x 10(-6) per year in the period 1968-1984. For juvenile papillomas the incidence rate was 3.62 x 10(-6), compared with 3.94 x 10(-6) for laryngeal papillomas of adult onset. When comparing different time periods a significantly low incidence was found in the time 1965-1968, while the incidence remained constant in 1969-1984. The low incidence rate in the early period may be real, but selectional bias may have played a part. It is general anticipated that maternal genital HPV-infections may serve as an HPV-reservoir, and that juvenile laryngeal papillomas is a result of HPV transmission from the mother to the child during birth. In the period in question cervical HPV-infections have been recorded with increasing frequency in younger women, indicating that the prevalence is rising. However, this is not reflected in the incidence of laryngeal papillomas.