Efficacy of Long-term Interferon-alpha Therapy in Adult Patients with Recurrent Respiratory Papillomatosis

Background: Since the early 1980s, interferon-alpha (IFN-α) has been used as adjuvant therapy in pediatric patients with recurrent respiratory papillomatosis (RRP). However, its efficacy in adults needs to be validated. Since 2002, Samsung Medical Center's guidelines have mandated regular injection of IFN-α in patients with RRP to prevent recurrence. To evaluate these guidelines, patient data were investigated. Methods: Five patients diagnosed as having RRP by bronchoscopy and histopathology were included. After initial bronchoscopic intervention, including laser cauterization, all patients received subcutaneous injection of 6 million units of IFN-α every 2 months. Further bronchoscopic intervention was carried out as needed. Patients were regularly evaluated using bronchoscopy or computed tomography. Results: The median age of the patients was 44 years (range 13-68), and the median duration of papillomatosis was 31 years (range 1-45). Three and two patients had juvenile-onset and adult-onset disease, respectively. Two patients had a history of tracheostomy at the time of diagnosis. The median duration of IFN-α therapy was 56 months (range 12-66). Two patients showed complete remission at 12 and 36 months after IFN-α injection, respectively. The other three patients showed partial remission, and the number of laser therapy sessions was significantly reduced. Conclusion: Intermittent IFN-α injection is effective in patients with long-standing RRP and can reduce the number of laser therapy sessions required in their treatment.