Juvenile onset recurrent respiratory papillomatosis: possibilities for successful antiviral therapy

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.

The use of antiviral drugs during the neonatal period

Parenteral therapy of viral infections of the newborn and infant began with vidarabine (adenine arabinoside) for the treatment of neonatal herpes simplex virus (HSV) infections in the early 1980s. Acyclovir has become the treatment of choice for neonatal HSV infections and a variety of other herpesvirus infections. Ganciclovir is beneficial for the treatment of congenital cytomegalovirus (CMV) infections involving the central nervous system (CNS). This article reviews the use of acyclovir and ganciclovir in the treatment of neonatal HSV and congenital CMV infections. A brief summary precedes a detailed discussion of available established and alternative therapeutics.

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.

Transbronchial Needle Injection: A Systematic Review of a New Diagnostic and Therapeutic Paradigm

BACKGROUND AND OBJECTIVE

Transbronchial needle catheters are commonly used during flexible and rigid bronchoscopy for needle aspiration. The use of these catheters can be expanded by employing the technique of transbronchial needle injection.

METHODS AND RESULTS

By injecting lesions in the airways, peribronchial structures, mediastinum, or lung parenchyma, transbronchial needle injection has been applied to the treatment of lung cancer, inflammatory disorders of the airways, recurrent respiratory papillomatosis, as well as bronchopleural fistulas. Diagnostic applications have included the localization of peripheral lung nodules as well as sentinel lymph nodes.

CONCLUSIONS

Our review defines this bronchoscopic technique and summarizes its various reported applications.

Human papillomavirus, viral load and proliferation rate in recurrent respiratory papillomatosis in response to alpha interferon treatment

The aim of this study was to identify recurrent respiratory papillomatosis patients who may benefit from interferon (IFN)-alpha treatment and to determine the means of IFN-alpha action. The presence of human papillomavirus (HPV) and viral load and proliferation rate in pre-, ongoing and post-treatment respiratory papillomatosis biopsies were examined retrospectively in 25 patients, 18 of whom were IFN-alpha treated and seven of whom were IFN-alpha non-treated. Using PCR, HPV was found to be present in 20/25 respiratory papillomatosis patients and HPV type was determined for 18/25 patients (12 HPV6 and six HPV11). Eighteen of the patients were treated with IFN-alpha, 14 of whom were HPV positive (eight HPV6, five HPV11 and one undefined HPV). Response to IFN-alpha therapy was observed in 12 patients (7/8 HPV6, 3/5 HPV11, 1/1 undefined HPV and 1/4 HPV negative), while six patients (1/8 HPV6, 2/5 HPV11 and 3/4 HPV negative) did not respond to therapy. Viral load, determined by quantitative real-time PCR (between 0.03 and 533 HPV copies per cell), and proliferation rate, determined as the percentage of Ki-67-positive cells (between 8 and 54 %), were similar in IFN-alpha-treated and non-treated patients and were generally unaffected by IFN-alpha treatment. In summary, most (12/18) IFN-alpha-treated patients responded to therapy. Moreover, there was a tendency for patients with HPV6-positive (7/8) respiratory papillomatosis to respond more frequently to IFN-alpha therapy than patients with HPV11 (3/5) or HPV-negative (1/4) respiratory papillomatosis. Finally, the presence of HPV and viral load and proliferation in respiratory papillomatosis biopsies was similar in patients treated or not with IFN-alpha and were in general unaffected by IFN-alpha treatment.

Overview of recurrent respiratory papillomatosis

PURPOSE OF REVIEW

The purpose of this article is to review recent literature regarding pediatric recurrent respiratory papillomatosis (RRP) published within the last year. By reviewing and assessing these articles, a more clear understanding regarding the etiology and management of pediatric RRP can be obtained, allowing physicians to better care for their pediatric RRP patients.

RECENT FINDINGS

Pediatric RRP continues to be an extremely difficult management problem for otolaryngologists. This disease process continues to be a significant burden on the health care system and is a significant cause of morbidity in affected patients and their families. The incidence of RRP continues to be approximately 3.96 per 100,000 in the pediatric population. It has been noted recently that approximately 7 of every 1000 children born to mothers with vaginal condyloma develop pediatric RRP. Although the mainstay of surgical management has traditionally been the CO2 laser, newer surgical techniques have demonstrated efficacy in the management of pediatric RRP patients, including powered instrumentation and the pulse-dye laser. The traditional adjuvant medical therapies used for pediatric RRP continue to be commonly used, including interferon-alpha2a, retinoic acid, and indol-3-carbinol/diindolylmethane (I3C/DIM). Recently cidofovir has demonstrated efficacy in selected patients. In addition, current research regarding vaccine therapy for pediatric RRP has shown promise. Basic science research in the field of immunology has demonstrated multiple defects in cell-mediated immunity, which has shed further light on the etiology of pediatric RRP.

SUMMARY

Pediatric RRP continues to be a highly morbid disease process. New surgical and medical therapies offer hope for better control of this disease in affected patients. Recent advances in immunologic research offer the hope of immune system modulation and augmentation as potential future treatment modalities to better control this disease process.

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.