P91: NOVEL TREATMENT OF RECURRENT RESPIRATORY PAPILLOMATOSIS

Abstract

Background: Recurrent respiratory papillomatosis (RRP) is a rare benign neoplasm of the respiratory tract caused by human papillomavirus types 6 and 11. Disease course is unpredictable, progressive and relapsing. Airway compromise is the major complication and may require repeated surgical debulking of the lesions leading to significant vocal cord scarring and laryngeal stenosis. Malignant transformation and parenchymal lesions are the main complications. To date there is no known universally effective therapy. Case report: We report a 17-year-old boy who presented at 6 months of age with persistence stridor and cough and a diagnosis of RRP - HPV-11 was made. Symptoms progressed and by 10 months laser microlaryngoscopy was required. In total he has had over 130 admissions to our hospital with over 80 surgical procedures. By 12 years the disease was affecting the trachea (70% obstruction), larynx and right main bronchus. By 13 years the disease was involving lung parenchyma with multiple cystic lesions seen on CT. He was requiring surgical intervention every 4-6 weeks. All adjuvant treatment modalities had failed to control the disease progression, some with an unacceptable side effect profile, including increased risk of malignancy and renal toxicity. Having exhausted standard treatments palliation was considered. Breakthrough treatment: Intralesional bevacizumab (Avastin), a recombinant humanised monoclonal IgG1 antibody that inhibits vascular endothelial growth factor (VEGF-A) by preventing receptor activation, was trialled as salvage therapy. This was followed 6 months later with oral Gefitinib, an epidermal growth factor receptor inhibitor in the tyrosine kinase domain. Both agents have continued. This has resulted in a significant improvement in quality of life and increasing intervals between surgical debridement. Conclusion: Intralesional bevacizumab and oral Gefitinib present a new treatment possibility for patients with RRP in whom other modalities have failed.