Three-year experience of treating recurrent respiratory papilloma with interferon.

This paper presents the 3-year follow-up of the original 19 patients with recurrent respiratory papilloma treated with exogenous alpha human leukocyte interferon (alpha-IFN) at the University of Iowa. Two patients were dropped from the study because of poor patient compliance, and one was lost to follow-up. After approximately 1 year of alpha-IFN treatment, five patients were clear, and the rest continued to have disease: seven mild, two moderate, and two severe. A second course of alpha-IFN was administered to eight patients, all of whom had a decrease in the volume of the papilloma. The reduction in anatomic distribution was variable. During the observation period all patients either cleared (50%), improved (25%), or continued with severe disease (25%). In summary, the response of recurrent respiratory papilloma to alpha-IFN therapy is dramatic in some patients and slight in others.