Intralesional injection of cidofovir for recurrent respiratory papillomatosis in children

Intralesional Cidofovir: A Systematic Review of Administration Protocols and Long-term Recurrence Rates in Adult and Juvenile Recurrent Respiratory Papillomatosis

OBJECTIVE

This is a systematic review aimed to explore Cidofovir administration protocols, recurrence rates, and long-term effectiveness for severe cases of recurrent respiratory papillomatosis (RRP). The primary goal was to identify current practices, determine the preferred protocol, and assess the adjuvant therapy's ability to prevent long-term papilloma recurrence in juvenile and adult-onset disease.

METHODS

The following databases were searched: Pubmed, Google Scholar (pages 1-10), EMBASE, Scopus, ISI (clarivate), Cochrane Library, and Journal Storage from 1996 to June 2022. Articles that reported the use of intralesional Cidofovir in RRP and reported remission/recurrence rates with follow-up were included in the review. The systematic review was registered through PROSPERO and contains the detailed protocol for the conduction of the review.

RESULTS

A total of 389 records were identified, 126 titles and abstracts screened, 45 studies fully read, and 30 studies met the inclusion criteria. Two hundred and fourteen adult-onset RRP (AORRP) and 126 juvenile-onset RRP (JORRP) cases were treated with Cidofovir across the included studies. There was no universal protocol for administering Cidofovir, with variations in concentration, treatment period, number and interval of injections, and follow-up duration. Most lesions showed human papilloma virus types 6 and 11. Recurrence rates varied, and other outcomes reported included remission rates, lesion reduction, surgical intervals, and side effects. Some studies demonstrated significant improvements in disease severity and extended intervals between recurrences after Cidofovir administration.

CONCLUSIONS

The analysis of 30 studies reveals the need for greater consistency in reporting treatment parameters and outcomes. The use of recurrence-free period as an outcome measure and the potential benefits of a concentration of 7.5 mg/mL are identified. Additionally, the importance of viral typing within papilloma lesions is emphasized. To further enhance understanding and establish optimal protocols, future research should focus on uniform reporting, including severity, dosage, interval, treatment duration, functional outcome, and related procedures.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022299549.

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.

How Enhancing Immunity to Low-Risk HPV Could Cure Recurrent Respiratory Papillomatosis

Recurrent respiratory papillomatosis (RRP) is currently treated with repeat surgical resection of papillomatous disease that does not address the fundamental underlying issue of chronic infection with low-risk human papillomavirus. Here, we review the biology and immunology of low-risk human papillomavirus (HPV) infections. Antiviral or antiangiogenic adjuvant treatments similarly address the papillomatous disease itself but do not activate HPV immunity. It is likely that only through immune-mediated clearance of low-risk HPV infection can patients with RRP be cured. In some patients, this occurs spontaneously. In others with more aggressive disease, adjuvant immunotherapy to activate immunity may be needed. Based on current understanding of antiviral immune responses, the only rational strategy to clear HPV-infected epithelial cells is through activation of the T-lymphocyte arm of the adaptive immune response. Translation of immunotherapies that are Food and Drug Administration-approved or under clinical study for cancer, such as immune checkpoint blockade or engineered therapeutic vaccines, may provide a path toward tolerable and efficacious adjuvant immunotherapy for RRP. LEVEL OF EVIDENCE: NA Laryngoscope, 131:2041-2047, 2021.

Voice Outcomes Following Multiple Surgeries for Recurrent Respiratory Papillomatosis

OBJECTIVES

Recurrent Respiratory Papillomatosis (RRP) is a rare disease caused by the human papilloma virus that presents as warty, exophytic growths in the upper airway. RRP in the larynx can lead to severe airway obstruction and voice changes. It is clinically known that patients with RRP frequently experience dysphonia. The purpose of this study was to assess the impact of multiple surgical treatments on RRP patients' voice outcomes, and to determine whether a higher number of repeated surgeries lead to decreased voice quality.

METHODS

A retrospective cohort study was conducted of adult RRP patients (n = 23) who underwent multiple surgeries. Group 1 included patients (n = 11) who had <5 surgeries (range 2-4 surgeries) and Group 2 included patients (n = 12) who had ≥5 surgeries (range 5-50+ surgeries). Voice recordings were selected from the following clinic visits: initial office visit (initial presurgery), first postsurgery, and the last clinic encounter(s) with no immediate planned surgery. Blinded auditory-perceptual ratings along with cepstral and spectral acoustic measures assessed voice severity.

RESULTS

There was significant improvement from the initial presurgery visit compared to each postoperative visit over time for all voice outcome measures for both Group 1 and Group 2. The results of the study indicated that the number of surgeries did not significantly affect mean postoperative voice outcomes, and there were no significant differences between patient groups for voice quality over time.

CONCLUSIONS

The results of this study suggest that RRP patients' voice quality may not suffer cumulative negative effects when using modern tissue-sparing surgical techniques.

Recurrent laryngeal papillomatosis with oesophageal involvement in a 2 year old boy: successful treatment with the quadrivalent human papillomatosis vaccine

Authors present a case report of a 2-year-old boy with recurrent laryngeal papillomatosis with oesophageal involvement due to human papilloma virus types 6 and 11, who needed surgical treatment every 4-6 weeks, altogether 11 times. After detailed immunological evaluation of basic immunological parameters, and in vitro detection of good responses to routine childhood immunization, a therapeutic vaccination has been decided with a 4-valent HPV vaccine. Following the third vaccine dose both laryngeal and oesophageal lesions disappeared completely, and for 2 years follow-up no papillomas could be detected. Vaccination could be a promising method in the treatment of RRP in children.

Diagnostic and therapeutic pitfalls in benign vocal fold diseases

More than half of patients presenting with hoarseness show benign vocal fold changes. The clinician should be familiar with the anatomy, physiology and functional aspects of voice disorders and also the modern diagnostic and therapeutic possibilities in order to ensure an optimal and patient specific management. This review article focuses on the diagnostic and therapeutic limitations and difficulties of treatment of benign vocal fold tumors, the management and prevention of scarred vocal folds and the issue of unilateral vocal fold paresis.

Systematic review of intralesional cidofovir dosing regimens in the treatment of recurrent respiratory papillomatosis

OBJECTIVE

Surgical management of recurrent respiratory papillomatosis (RRP) usually involves resection via microlaryngoscopy. Intralesional injection of cidofovir has been shown to be an effective adjuvant treatment, but remains unlicensed. United Kingdom General Medical Council guidelines recommend the prescribing doctor should "be satisfied that there is a sufficient evidence base and/or experience of using the medicine to demonstrate its safety and efficacy". This study reviews the published dosing regimens of intralesional cidofovir in the treatment of RRP in order to provide a precedent for those that wish to prescribe it.

METHODS

A systematic review of the literature was undertaken using Medline, EMBASE and CINAHL. Articles describing the use of intralesional cidofovir for RRP were reviewed. Information regarding cidofovir concentration, volume, total dose, number of treatments, interval between treatments, overall treatment period and follow up was extracted.

RESULTS

Fifty-one articles were identified. Concentration of cidofovir injected ranged from 0.0001mg/ml to 37.5mg/ml, with 5 to 7.5mg/ml being the most common. The volume of cidofovir solution injection ranged from 0.1 to 20ml. The total dose per injection ranged from 0.15 to 105mg. There was wide variation in dosing regimens with different intervals between endoscopies, number of injections and total doses delivered.

CONCLUSIONS

Based on this published literature, the precedent for prescribing intralesional cidofovir supports a concentration of 5 to 7.5mg/ml. Volumes up to 5ml per injection are routinely used. Total dose and frequency of cidofovir administration is highly variable. The need for repeat doses of cidofovir should be judged on an individual basis.

Does food intolerance play a role in recurrent respiratory papillomatosis?

BACKGROUND

The purpose of this study is to evaluate the potential role of food intolerances in the management of recurrent respiratory papillomatosis (RRP).

METHODS

This is a retrospective case review of 4 pediatric patients with RRP. All of the patients, cared for by the primary author between 2005 and 2010, were managed using microdebrider resection, intralesional injection of cidofovir, and required multiple surgeries. Skin prick test (SPT) and/or radioallergosorbent test (RAST) were obtained for 2 patients. Oral food challenge was utilized in all 4 patients.

RESULTS

Standard SPT and RAST did not identify any immunoglobulin E (IgE)-based allergens. A detailed medical history followed by an oral food challenge was successful at identifying food intolerances in all 4 patients. When specific food elimination was implemented in these patients' treatments in addition to microdebrider resection and cidofovir injection, statistically significant long-term remissions were achieved.

CONCLUSION

Food intolerance and its impact on RRP and immune dysfunction deserve further investigation and may benefit some patients with RRP.

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.

Novel human papilloma virus (HPV) genotypes in children with recurrent respiratory papillomatosis

INTRODUCTION

Recurrent respiratory papillomatosis (RRP) is characterized by the presence of benign virally induced tumors of the larynx and respiratory epithelium that may obstruct the airway and tend to recur frequently. RRP is caused by the human papilloma virus (HPV), most frequently by HPV types 6 and 11. In this study, we present four cases of children with RRP in whom HPVs other than HPV-6 or HPV-11 were found.

MATERIAL AND METHODS

In all four cases, HPV typing was performed by polymerase chain reaction (PCR) followed by restriction digestion (RFLP) in biopsy samples collected during surgery.

RESULTS

In the first case, simultaneous HPV infection with types 13 and 39 was detected, while in the second case HPV-40 and HPV-56 were found. In cases 3 and 4, the biopsy samples were positive for unidentified 'low-risk' HPVs.

CONCLUSIONS

The presence of novel HPV genotypes in children with RRP emphasizes the need for further investigation of the implication of these genotypes in the disease.

[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.

A controlled safety study of diindolylmethane in the immature rat model

OBJECTIVES/HYPOTHESIS

Diindolylmethane (DIM), a natural product from cruciferous vegetables, has been shown to be a dietary component that has inhibitory effects on some tumors (e.g., laryngeal papilloma). However, current evidence to support its safety is based on adult humans or mature animals. There is little to show on its safety in children. This study is designed to assess safety in the young rat model.

STUDY DESIGN

Prospective controlled animal study.

METHODS

Forty rats were separated into four treatment groups of 10 rats each, based on the amount of study drug they received in their daily food: 1) immature rats fed a low dose of DIM, (0.6 mg/kg/day); 2) immature rats fed a high dose of DIM (6.0 mg/kg/day); 3) immature rats fed no DIM (control); and 4) adult rats fed a high dose of DIM (6.0 mg/kg/day). At the conclusion of the study we collected blood to compare serum chemistries and vitamin D levels, and harvested organs to observe for any gross or histological changes among the groups. Statistical methods involved one-way analysis of variance and pairwise comparisons with Tukey multiple comparison adjustment.

RESULTS

Although our numbers do not allow for statistical significance, there was no appreciable difference in rat weights among the immature groups, nor was there appreciable difference in serum chemistries, or gross or histological examination of liver, kidney, and bone.

CONCLUSIONS

Diindolylmethane seems to have no adverse affects on the rat even when given in doses 3x what we propose to be therapeutic. This adds evidence to the safety of this drug in the pediatric population as a treatment option for recurrent respiratory papilloma.