IT HAS been repeatedly pointed out in the literature that papillomatosis of the larynx and trachea often recurs and not infrequently degenerates into a malignant tumor (Semon, 1894; Schollmeyer, 1936; Ch. Jackson and C. Jackson, 1939; L. R. Zak, 1954; B. A. Lemberskii, 1955; D. E. Chernov, 1957; I. A. Voznesenskaya, 1958; G. M. Mnukhina, 1959; A. S. Samokhvalova and A. V. Nezhintseva, 1961; M. I. Svetlakov, 1964, and others). Numerous observations showed that a complex method of therapy, including surgical intervention and medicinal radiation treatment, gives the best results in the presence of the described disease (A. A. Smutneva, 1957; I. A. Voznesenskaya, 1958; Z. M. Grekova, 1958; A. I. Lisovskaya, 1959; A. S. Samokhvalova and S. N. Olenev, 1961; N. F. Lebedev, 1961, and others). Nevertheless, even after such treatment, regenerations of the papilloma of the larynx and trachea often occur. With the aim of systematically preventing them