Cidofovir for the Treatment of Recurrent Respiratory Papillomatosis: A Review of the Literature

Recurrent respiratory papillomatosis disease course in immunosuppressed populations

OBJECTIVE

Recurrent respiratory papillomatosis is a benign manifestation of human papillomavirus types 6 and 11 in the respiratory tract. Disease is recurrent, and factors predicting these recurrences and severity of disease are incompletely characterised. This retrospective cohort study examined the relationship of immunosuppression with recurrent respiratory papillomatosis morbidity.

METHODS

A retrospective cohort of 97 adult patients with recurrent respiratory papillomatosis treated at a tertiary referral centre from 2005 to 2020 was conducted. Measures assessed included inter-surgical interval, Voice Handicap Index ('VHI-10') and anatomical Derkay scores.

RESULTS

Bivariate analyses comparing average inter-surgical interval, Voice Handicap Index and Derkay scores in immunosuppressed and healthy patients were insignificant. When controlling for diabetes mellitus and comparing immunosuppressed to healthy patients, inter-surgical interval and Voice Handicap Index change were insignificant (p = 0.458 and p = 0.465, respectively).

CONCLUSION

Recurrent respiratory papillomatosis morbidity for immunosuppressed patients did not significantly differ from that of immunocompetent patients.

Assessment of immunomodulation and regulation of cell cycle in epithelium and stroma after Cidofovir injection in patients with recurrent respiratory papillomatosis-Pilot study

Recurrent respiratory papillomatosis is strictly connected with human papillomavirus (HPV) infection of the epithelium of the upper respiratory tract. The main treatment of lesions located in the larynx or lower pharynx includes microsurgical excision by using a CO₂ laser. To decrease the amount of surgical procedures gain in importance combined therapy with antiviral agents. The aim of this study was to investigate the effect of the intralesional application of Cidofovir on the tissue of laryngeal papillomas. We have shown that simultaneous microsurgery with adjuvant therapy of Cidofovir reduces chronic inflammation (by measuring the expression of CD4 and CD8 in tissue samples), cell proliferation, and regulates the cell cycle of HPV-infected cells by reducing the expression of p53 and p63 proteins. In addition, this strategy reduces the multiple surgical procedures and regrowth of the pathology.

Infantile recurrent respiratory papillomatosis: review of adjuvant therapies

BACKGROUND

Recurrent respiratory papillomatosis is a potentially life-threatening condition characterised by the growth of exophytic lesions within the larynx and trachea. The principal aim of management is maintenance of an adequate airway by surgical debulking. Several adjuvant therapies have been used to varying effect to reduce the burden of this disease and increase the interval between debulking procedures. The most severe cases present in children aged under three years, who are therefore most likely to need adjuvant therapies. The current evidence base on adjuvant treatments relating to children who present aged under three years has been reviewed.

METHODS

A literature review of articles in Cochrane, PubMed and Embase databases was carried out. Given the rarity of the condition in this age group, all the literature relates to case reports and case series.

RESULTS AND CONCLUSION

The following adjuvant therapies have been used in children who presented under three years of age: quadrivalent human papilloma virus vaccine, intralesional cidofovir, pegylated interferon, alpha-interferon, cimetidine and cetuximab.

Drug delivery to the pediatric upper airway

Pediatric upper airway disorders are frequently life-threatening and require precise assessment and intervention. Targeting these pathologies remains a challenge for clinicians due to the high complexity of pediatric upper airway anatomy and numerous potential etiologies; the most common treatments include systemic delivery of high dose steroids and antibiotics or complex and invasive surgeries. Furthermore, the majority of innovative airway management technologies are only designed and tested for adults, limiting their widespread implementation in the pediatric population. Here, we provide a comprehensive review of the most recent challenges of managing common pediatric upper airway disorders, describe the limitations of current clinical treatments, and elaborate on how to circumvent those limitations via local controlled drug delivery. Furthermore, we propose future advancements in the field of drug-eluting technologies to improve pediatric upper airway management outcomes.

Evaluation of Safety of Intralesional Cidofovir for Adjuvant Treatment of Recurrent Respiratory Papillomatosis

Importance

The use of intralesional cidofovir injections for recurrent respiratory papillomatosis (RRP) remains controversial owing to concern regarding the risks of its use, including increased risk of dysplasia or carcinogenesis.

Objective

To describe the rates of dysplasia, development of malignant lesions, and adverse events associated with use of intralesional cidofovir injections as adjuvant treatment for RRP compared with patients treated without adjuvant cidofovir.

Design, Setting, and Participants

In this case series performed at a tertiary care referral center, review of electronic medical records on all adult and pediatric patients (N = 154) treated for RRP with adequate follow-up from January 1, 2000, to December 31, 2016, was performed. Data were collected on the use of cidofovir, development and presence of dysplasia or malignant lesions, complications, and intersurgical interval.

Exposures

Adjuvant intralesional cidofovir or surgical excision only.

Main Outcomes and Measures

The main outcomes measured were the development of dysplasia, malignant lesions, and complications from treatment. These outcomes were determined before collection of data.

Results

Of the 154 patients included in the analysis, 83 patients (53.9%) received adjuvant intralesional cidofovir and 71 patients (46.1%) underwent surgical excision only. One hundred patients (64.9%) were male; mean age was 27.7 (95% CI, 24.3-31.2) years. Patients were followed up for a median (interquartile range) of 70 (24-118) months in the noncidofovir group and 91 (47-152) months in the cidofovir group. There were no statistically significant differences in the rates of development of dysplasia (2.8%; 95% CI, -8.3% to 13.2%) or malignant lesions (2.2%; 95% CI, -5.3% to 11.2%) between the groups. No nephrotoxic effects were observed in the treated cohort, and only 5 minor complications that occurred in 628 injections were noted in the cidofovir group; 3 were related to direct laryngoscopy and 2 were related to needle malfunction.

Conclusions and Relevance

In this cohort of patients with RRP, adjuvant intralesional cidofovir injections did not appear to cause major complications or an increased rate of development of dysplasia and cancer.

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

Background

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

Methods

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

Results

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

Conclusion

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

Current and future management of recurrent respiratory papillomatosis

Objectives

Recurrent respiratory papillomatosis (RRP) is a chronic disease of the respiratory tract that occurs in both children and adults. It is caused by the human papillomavirus (HPV), in particular low‐risk HPV6 and HPV11, and aggressiveness varies among patients. RRP remains a chronic disease that is difficult to manage. This review provides perspectives on current and future management of RRP.

Results

The current standard of care is surgical excision, with adjuvant therapies as needed. Surgical management of RRP has evolved with the introduction of microdebriders and photoangiolytic lasers; the latter can now be used in the office setting. Numerous adjuvant pharmacologic therapies have been utilized with some success. Also, exciting preliminary data show that HPV vaccines may prolong the time to recurrence in the RRP population. There is also optimism that wide‐spread HPV vaccination could reduce RRP incidence indirectly by preventing vertical HPV transmission to newborns.

Conclusion

To date, the biology of RRP is not well understood, although it has been noted to become more aggressive in the setting of immune suppression. Additional research is needed to better understand immune system dysfunction in RRP such that immunomodulatory approaches may be developed for RRP management.

Level of Evidence

4

Treatment With Quadrivalent Human Papillomavirus Vaccine for Juvenile-Onset Recurrent Respiratory Papillomatosis: Case Report and Review of the Literature

Although juvenile-onset recurrent respiratory papillomatosis (JoRRP) generally involves a benign tumor on the larynx and other respiratory tract areas, almost all patients with this disease require repeated surgical intervention (to prevent airway obstruction during the course of illness) and various adjuvant therapies such as interferon, cidofovir, acyclovir, ribavirin, indole-3-carbinol, HspE7, mumps vaccine, photodynamic therapy, propranolol, cimetidine, and bevacizumab. Some case reports recently described the effectiveness of the quadrivalent human papillomavirus vaccine (HPV4) as an adjuvant therapy. On the basis of these reports, we administered HPV4 to a 2-year-old boy with JoRRP. However, no therapeutic effect was found. A review of the available literature revealed that current evidence for the effectiveness of therapeutic HPV4 and other adjuvant therapies for JoRRP is inconsistent. Therefore, the prophylactic use of currently available HPV vaccine for adolescents is the most effective strategy for preventing not only anogenital cancers but also genital warts, which might be a risk factor for JoRRP among their children in the future.

Recurrent respiratory papillomatosis: current and future perspectives

Although recurrent respiratory papillomatosis is a benign disease of the upper aerodigestive tract caused by infection with human papillomavirus, the disease process is unpredictable, ranging from mild disease and spontaneous remission to an aggressive disease with pulmonary spread and requirement for frequent surgical debulking procedures. It can present a protracted clinical course and cause potentially life-threatening compromise of the airways. Over recent decades, a number of alternative medical therapies to standard surgical treatment have been investigated, with modest outcomes overall. Currently, some additional therapies are being explored, together with novel surgical instrumentation that can help to avoid inevitable long-term stenotic complications, ultimately affecting quality of life. Hopefully, clinicians might soon be able to significantly improve the quality of treatment and outcomes for patients affected with recurrent respiratory papillomatosis, with human papillomavirus vaccination having a potentially important role.

Voice and quality of life in patients with recurrent respiratory papillomatosis in a northern Sweden cohort

CONCLUSION

The frequency of operations, age at onset, gender and subtype of the human papilloma virus (HPV) may be used as factors to predict voice disability.

OBJECTIVES

Patients with recurrent respiratory papillomatosis (RRP) are characterized by morbid consequences due to a lifelong repetitive influence on voice and breathing ability and the need for recurrent surgical treatments. The aim of the study was to measure the quality of voice and life using evaluated and validated questionnaires in a northern Sweden RRP population.

METHODS

A total of 27 consecutive patients with RRP (age 21-71 years, median 47 years) were evaluated 3 months postoperatively (CO2 laser treatment) using the voice handicap index (VHI) and SF-36 questionnaires to assess the impact on life and voice in an RRP population. The values were compared to historical normative data, VHI ≤ 20.

RESULTS

Patients that underwent more than one operation per year were younger (p = 0.028) than those treated less frequently. The mean VHItotal score in patients with RRP was 39.3, indicating a statistically significant impairment of voice quality (p < 0.001) as compared with normal subjects. Voice dysfunction was observed in 21 patients (78%). Significantly lower values than the normal population regarding the quality of life in patients with RRP were obtained in the domain of social functioning (p = 0.029). Females, patients with frequent surgical treatment sessions and patients with the high-risk HPV types scored significantly lower in several domains of the quality of life assessment as compared with normal subjects. The results should be interpreted with caution due to the limited number of subjects.

Treatment of paediatric laryngeal papillomas: web survey of British Association of Paediatric Otolaryngologists

Background and objective:

Recurrent respiratory papillomatosis is the most common benign neoplasm of the larynx in children. Intralesional injection of cidofovir may have some potential as an adjunctive treatment. There is no standardised protocol in the UK for the management of recurrent respiratory papillomatosis. This study aimed to investigate the management practices of surgeons treating paediatric recurrent respiratory papillomatosis in the UK.

Method:

A web questionnaire survey was sent by e-mail to all members of the British Association of Paediatric Otorhinolaryngology.

Results:

Out of 35 respondents, 23 were at that time treating children with recurrent respiratory papillomatosis. Nineteen respondents preferred to use a microdebrider, 12 preferred laser, and 5 preferred cold steel along with either laser or a microdebrider. Twelve surgeons used cidofovir for selected patients and 12 surgeons did not use cidofovir for any patients. Cidofovir was considered after 0–4 surgical procedures by seven respondents, after 4–6 surgical procedures by four respondents and after 6 surgical procedures by six respondents. Eleven respondents warned patients about the possible side effects of cidofovir and five gave no warning.

Conclusion:

There was no consensus as to when it would be appropriate to use cidofovir, indicating the need for cidofovir usage guidelines.

Rare case of malignant transformation of recurrent respiratory papillomatosis associated with human papillomavirus type 6 infection and p53 overexpression

Recurrent respiratory papillomatosis (RRP), a chronic upper respiratory condition characterized by diffuse multiple recurring papillomas, is thought to result from human papillomavirus (HPV) type 6 or 11 infection. Although RRP is an intractable disease, malignant transformation of RRP is rare. The underlying mechanism, however, has not been elucidated. We describe the clinical course of a patient who underwent more than 130 operations for RRP associated with HPV type 6 infection and subsequently suffered spontaneous malignant transformation to squamous cell carcinoma. Immunohistochemical analysis revealed that malignant transformation might result from a genomic defect, such as p53 inactivation, leading to stimulation of uncontrolled cell proliferation by HPV type 6 for an extended period, but not directly because of HPV itself. Our results could help in the development of novel therapeutic strategies for severe RRP, although further studies are required before clinical application of molecular targeted therapies.

Safety of intralesional cidofovir in patients with recurrent respiratory papillomatosis: an international retrospective study on 635 RRP patients

Intralesional use of cidofovir (Vistide(®)) has been one of the mainstays of adjuvant therapy in patients with recurrent respiratory papillomatosis (RRP) since 1998. In 2011, a communication provided by the producer of cidofovir addressed very serious side effects concerning its off-label use. As this was a general warning, it was inconclusive whether this would account for its use in RRP. The aim of this study is to determine whether nephrotoxic, neutropenic, or oncogenic side effects have occurred after intralesional use of cidofovir in patients with RRP. Update of recent developments in RRP, a multicentre questionnaire and a multicentre retrospective chart review. Sixteen hospitals from eleven countries worldwide submitted records of 635 RRP patients, of whom 275 were treated with cidofovir. RRP patients received a median of three intralesional injections (interquartile range 2-6). There were no statistical differences in occurrence of neutropenia or renal dysfunction before and after cidofovir. There was no statistical difference in occurrence of upper airway and tracheal malignancies between the cidofovir and the non-cidofovir group. In this retrospective patient chart review, no clinical evidence was found for more long-term nephrotoxicity, neutropenia or laryngeal malignancies after the administration of intralesional cidofovir in RRP patients.

Safety and dosing of bevacizumab (avastin) for the treatment of recurrent respiratory papillomatosis

OBJECTIVES

Increasing evidence supports the use of laryngeal injections of the antiangiogenic agent bevacizumab (Avastin) for the adjuvant treatment of recurrent respiratory papillomatosis (RRP). A recent prospective open-label investigation, approved by the US Food and Drug Administration, employing 12.5 mg of sublesional bevacizumab demonstrated single-site efficacy without complications; however, the safety of multiple-site injections and higher dosing has not yet been reported. The primary objective of this study was to report on the safety of increased doses of bevacizumab for the treatment of RRP.

METHODS

Two cohorts of adult patients were evaluated. In the first group, a prospective analysis was performed on patients with a diagnosis of laryngeal RRP after t heir participation in th e initial clinical trial with a single-site lowerdose (7.5 to 12.5 mg). They received higher doses of sublesional laryngeal bevacizumab (15 to 50 mg total) with detailed physiologic, hematologic, and serum chemistry measurements performed before and after each bevacizumab injection. A second cohort of patients received sublesional laryngeal injections of bevacizumab (15 to 88 mg total) without physiologic measurements and underwent a retrospective analysis of reported complications.

RESULTS

One hundred consecutive laryngeal injection sessions (office, 87; operating room, 13) with bevacizumab were performed in 43 patients, with a mean dose of 30 mg total per treatment (range, 15 to 88 mg). Sixty-three of the 100 sessions were accompanied by KTP laser photoangiolysis of the papilloma prior to bevacizumab injections. Eighteen patients (cohort 1) underwent detailed physiologic assessment, and no dysfunction was observed. There were no local or systemic complications of bevacizumab administration. The second group of 25 patients (cohort 2) also reported no significant local or systemic complications. Neither patient group was observed to have a local wound problem in the larynx.

CONCLUSIONS

This investigation provides evidence that higher doses of bevacizumab are relatively safe in adult patients with laryngeal RRP. Further refinements in pharmacologic concentration and drug delivery will determine the optimal treatment regimens in the future.

Recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is a rare, benign disease with no known cure. RRP is caused by infection of the upper aerodigestive tract with the human papillomavirus (HPV). Passage through the birth canal is thought to be the initial transmission event, but infection may occur in utero. HPV vaccines have helped to provide protection from cervical cancer; however, their role in the prevention of RRP is undetermined. Clinical presentation of initial symptoms of RRP may be subtle. RRP course varies, and current management focuses on surgical debulking of papillomatous lesions with or without concurrent adjuvant therapy.

Effectiveness of cidofovir intralesional treatment in recurrent respiratory papillomatosis

To present the results of recurrent respiratory papillomatosis (RRP) treatment with surgical excision and adjuvant anti-viral cidofovir intralesional use and to examine the correlation between the cidofovir effectiveness and the patient previous history of multiple larynx procedures, age, extension of lesion and dose. 32 patients with laryngeal papillomas were treated with cidofovir in our Department between I.2009 and I.2011. The number of previous RRP debulking procedures ranged from 1 to 100. The intensity of papillomatosis differed from one anatomic site and moderate growth to four or five localizations with heavy extension. The number of injections per patient varied from 1 to 7, and the total volume of 5 mg/ml solution varied from 2 to 33 ml. The injections were combined with laser debulking of the lesions. In disperse papillomata, the injections were administered in particular anatomical sites in 4–6 weeks intervals, in massive lesions injections were repeated in the same anatomical site in 2–4 weeks. Complete remission was observed in 18 out of 32 patients. 13 patients showed remission in a place of cidofovir injection. One patient did not react to the drug. In four patients, new changes in injection places appeared. In two patients, hepatic toxic side effects were observed. Intralesional cidofovir injection has been shown to be an effective and safe therapy for laryngeal papillomatosis and should be considered in those patients who experienced disease relapse.

Novel method of intralesional cidofovir injection into laryngotracheal papillomata

Laryngeal papillomatosis is characterised by multiple papillomata affecting the upper respiratory tract. This condition is difficult to treat due to its recurrent nature. Treatment often involves surgical debulking. A number of non-surgical treatments have been reported. Intralesional cidofovir, a cytosine nucleoside analogue with antiviral activity, has been used in an attempt to manage the condition. We present a novel technique of administering cidofovir in a case of recurrent laryngotracheal papillomata.

Natural Progression of Dysplasia in Adult Recurrent Respiratory Papillomatosis

Objectives. Recurrent respiratory papillomatosis (RRP) is often described as a benign disease. However, the natural progression of dysplasia and transformation to squamous cell carcinoma has not been elucidated for RRP. This study delineates our extensive experience with dysplasia in RRP.

Study Design/Setting. Case series with chart review.

Subjects and Methods. Demographic data and surgical pathology were analyzed for patients diagnosed with RRP at greater than 18 years of age who underwent operative intervention without cidofovir treatment for RRP between 2004 and 2009.

Results. Fifty-four patients were identified. Dysplasia was identified in 27 of 54 patients (50%). Of the 54 patients, 50% had no dysplasia, 26% had mild dysplasia (grade 1), 11% had moderate dysplasia (grade 2), 4% had severe dysplasia (grade 3), 7% had carcinoma in situ, and 2% had squamous cell carcinoma as the highest documented degree of dysplasia. Thirty of 54 patients (55.6%) had 2 or more operative interventions. Nine of the 30 patients (30%) developed a higher dysplastic grade during the course of treatment. Time to progression averaged 16.2 ± 8.7 months for patients with initially benign disease. Of those patients with dysplasia progression, only 1 of 9 (11.1%) developed squamous cell carcinoma. Patients presenting with benign or mild dysplasia typically did not progress beyond mild dysplasia (22 of 24, 91.7%).

Conclusions. Dysplasia is common in RRP. Progression of dysplasia, especially with an initial dysplastic grading of benign or mild disease, is rare.

Yet another ten stories on antiviral drug discovery (part D): paradigms, paradoxes, and paraductions

This review article presents the fourth part (part D) in the series of stories on antiviral drug discovery. The stories told in part D focus on: (i) the cyclotriazadisulfonamide compounds; (ii) the {5-[(4-bromophenylmethyl]-2-phenyl-5H-imidazo[4,5-c]pyridine} compounds; (iii) (1H,3H-thiazolo[3,4-a]benzimidazole) derivatives; (iv) T-705 (6-fluoro-3-hydroxy-2-pyrazinecarboxamide) and (v) its structurally closely related analogue pyrazine 2-carboxamide (pyrazinamide); (vi) new strategies for the treatment of hemorrhagic fever virus infections, including, as the most imminent, (vii) dengue fever, (viii) the veterinary use of acyclic nucleoside phosphonates; (ix) the potential (off-label) use of cidofovir in the treatment of papillomatosis, particularly RRP (recurrent respiratory papillomatosis); and (x) finally, the prophylactic use of tenofovir to prevent HIV infections.

[The schedule of intralesional papillomatosis treatment with cidofovir]

INTRODUCTION

Recurrent respiratory papillomatosis (RRP) is a rare disease in children and adults. It is characterized by proliferation of benign squamous cell papillomas within the respiratory-digestive tract, predominantly the larynx. Standard treatment consists of surgical excision of papillomata to maintain airway patency and voice quality. For last several years cidofovir is the most contemporary adjuvant anti-viral treatment for recurrent respiratory papillomatosis and its topical use is widely described.

MATERIAL AND METHODS

Intralesional cidofovir therapy was given to 20 patients treated for laryngeal papillomas in the Department of Otolaryngology in Poznan between I-XII.2009. The character of the lesion differed: from one anatomical site and moderate growth to four or five localizations with heavy extension. The number of cidofovir injections per patient varied from one to six times and the volume of solution ranges from 1-12 ml. The cidofovir injections were combined with laser or mechanical excision of the lesions. In disperse papillomata the injections administered in particular anatomical sites in 4-6 weeks period. In massive lesions injections were repeated in the same anatomical site.

RESULTS

Complete remission was observed in 3 out of 20 patients. 12 patients show remission in a place of cidofovir injection. In 4 patients during the 4 week observation new foci of papillomatosis occurred. In two patients hepatic toxic side effect were observed.

CONCLUSIONS

Intralesional cidofovir injection has been shown to be an effective an safe therapy for laryngeal papilloma and should be considered in those patients who experienced disease relapse.

Topical treatment of CIN 2+ by cidofovir: results of a phase II, double-blind, prospective, placebo-controlled study

OBJECTIVE

Randomized controlled trial evaluating a topical treatment for cervical intraepithelial neoplasia 2 and 3 (CIN 2+) using cidofovir.

METHODS

Fifty-three women with a biopsy-proven CIN 2+ were randomly assigned, 6 weeks before their planned conisation, either 3 applications of 3 ml 2% cidofovir in Intrasite gel in a cervical cap or a placebo (the same volume of Intrasite alone). A cervical sample for high-risk types of human papillomaviruses (HPV) (Hybrid Capture 2 or HC2) was taken before treatment and before conisation. The cone was submitted for pathological examination, and subsequently, along with the initial biopsy, to in situ hybridization (ISH) for high-risk HPV.

RESULTS

Forty-eight patients were treated and followed according to the protocol, (23 cidofovir, and 25 placebo). Fourteen of the 23 cones were free of any CIN (60.8%) in the cidofovir group. Only 5 of 25 cones were free of any CIN (20%) in the placebo group (p<0.01). The difference remained significant in the ITT group (p<0.05). In the per-protocol and ITT populations, we observed more frequent viral clearance in the cidofovir group, but the difference was significant only when evaluated by ISH and not by HC2. No systemic toxicity was observed. Cervico-vaginal side effects of cidofovir were limited, and not statistically different from placebo.

CONCLUSION

The medical topical treatment with cidofovir, at this point, cannot replace conisation, but it is a promising candidate for topical chemotherapy of CIN 2+ lesions; a larger prospective randomized study is needed to confirm our results.

Squamous cell carcinoma associated with intralesional injection of cidofovir for recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis is a common neoplasm of the larynx that may lead to severe, recurrent lesions. Intralesional injection of cidofovir has shown promise as an adjuvant therapy. There is concern for possible malignant transformation with its use but, to our knowledge, this has not been documented in the literature. We report a case of invasive squamous cell cancer arising from squamous papilloma in a patient treated with multiple injections of cidofovir. Although causation is not shown, we believe the association presented is a valuable addition to the literature and an important consideration in the use of cidofovir.

[Laryngeal papillomatosis: etiology, diagnostics and therapy]

Papillomas are rare tumors that originate from the mucosa. They may appear in the nose, paranasal sinuses, oral cavity, larynx, trachea, or the skin. Papillomas are mainly asymptomatic and are therefore mostly diagnosed coincidentally. In contrast, laryngeal papillomatosis may cause stridor, dyspnoea, and hoarseness. A viral cause of the disease seems likely, especially human papilloma virus. Mechanical irritation is also a possible reason when the nose, oral cavity, or oropharynx is affected. All papillomas, independent of their origin, may recur, and have the possibility of malignant degeneration in common. The therapy of choice is complete surgical excision. Regarding laryngeal papillomatosis, laser vaporisation or excision using the CO(2)laser is recommended. Because retreatments using conventional modalities are frequently necessary, especially in the case of laryngeal papillomatosis, adjuvant therapies are applied with the aim of reducing the recurrence rate and prolonging the interval between treatments.

Surgery and topic cidofovir for nasal squamous papillomatosis in HIV+ patient

Intranasal schneiderian exophytic squamous papillomatosis is rare and often secondary to human papilloma virus infection. Treatment usually consists of repeated surgical or endoscopic excisions due to recurrences. The use of intravenous or intralesional or topically applied cidofovir, a cytidine nucleotide analogue suppressing viral replication, alone or as adjuvant therapy has been proposed and described in the literature for the treatment of other human papillomavirus (HPV)-related lesions. We firstly describe a successful combined approach of surgery and topical cidofovir for recurrent nasal HPV-related exophytic squamous papillomatosis in a HIV-infected patient. As no untoward effects were encountered this therapeutical option should be considered in the management of recurrent nasal papillomatosis in HIV-infected patients.

Aggressive recurrent respiratory papillomatosis in a neonate

Recurrent respiratory papillomatosis is the most common benign laryngeal neoplasm in children. We report an infant with widespread papillomatosis at the time of diagnosis and rapidly progressive disease as a neonate. This child did not have the usual risk factors for recurrent respiratory papillomatosis, being the second child born by cesarean section to a mother without history of condyloma. Repeated surgical debulking has been used to control the disease, along with adjuvant therapies that included systemic therapy with an epidermal growth factor receptor inhibitor and intralesional cidofovir. We report our experience with these therapies.

[Extensive oral condylomas treated by in situ cidofovir injection in an HIV patient]

BACKGROUND

Human papillomavirus infections are difficult to treat and have a high rate of recurrence, especially in a setting of human immunodeficiency (HIV) infection. Moreover, there is no standard treatment for oral condylomas.

PATIENTS AND METHODS

We report the partial success of in situ injections of cidofovir in an HIV patient, presenting extensive oral condylomas. The injections were well tolerated and the response was still present at one year while the immune status of the patient was unchanged.

DISCUSSION

The efficacy of topical cidofovir against condyloma acuminata has been reported and the value of in situ cidofovir injections for the treatment of laryngeal papillomatosis is well established. This case report shows the need for further investigation of in situ cidofovir injections as an alternative treatment for human papillomavirus lesions that are difficult to treat because of both site and extension.

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.

Local administration of cidofovir for human papilloma virus associated skin lesions in transplant recipients

Human papilloma virus (HPV)-associated diseases are increasingly diagnosed in solid organ recipients. Cidofovir (CDV) is a broad-spectrum antiviral agent with activity against all human herpes viruses and HPV. From 2000-2004, a total of 1303 solid organ transplants (SOT) were performed at our center. Six transplant recipients were treated with topical CDV for HPV-associated lesions. One cardiac recipient responded to a single injection of CDV into his recurrent anal condylomata. In a renal recipient with recurrent penile condylomata CDV was injected into the lesions four times (2 week interval) until lesions regressed. One renal recipient developed multiple vaginal and anal intradermal neoplasias, which relapsed after laser ablation. The lesions were repeatedly injected with CDV and completely disappeared. Two renal recipients with widespread verrucae vulgares were treated with CDV gel, which resulted in regression of the lesions. One patient developed donor derived verrucae vulgares on both transplanted hands, which responded to CDV gel. Four of the six patients were switched from calcineurin inhibitors (CNIs) to Sirolimus (SIR). CDV was found effective in the treatment of HPV-associated skin lesions in SOT recipients. It needs to be determined whether switch from CNIs to SIR might have contributed to the beneficial effect of CDV.

Papillomavirus and treatment

Human papillomaviruses (HPVs) are small DNA viruses responsible for a broad range of clinical presentations, characterized histologically by the proliferation of epithelial cells. HPVs are responsible for benign as well as malignant lesions, the most frequent of the latter being cervical carcinoma. A better knowledge of the immunobiology of these lesions allowed the development of prophylactic vaccines (for the most frequent genital types) that are presently under evaluation. The present paper describes different approaches for the treatment of HPV lesions, still mostly based on surgery, and underlines the importance of developing adjuvant therapies.

Recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is a benign, often multi-focal neoplasm. A potentially fatal manifestation of human papilloma virus infection, the condition is characterised by multiple warty excrescences on the mucosal surface of the respiratory tract. RRP is rare--incidence is estimated at 3.5 per million person-years, with a prevalence of 4 in 100,000 children. Affected children usually require multiple interventions; the impact on patients, their families, and the healthcare system is considerable. Treatment of RRP accounts for an estimated dollar 109 million annual expenditure in the USA.