Regression of flat warts and common warts

Abstract

Wart (human papilloma) is such a common disease that even a child can make a diagnosis at a glance. Furthermore, from our long experience, we are aware that warts often disappear in a short period of time, spontaneously or after various magical rituals that are prevalent in different parts of the world. In Japan, we can find some shrines or temples in every district where ardent worshipers make pilgrimages in search of quick answers to their prayers to cure their warts. Evaluation of clinical effectiveness of a new therapeutic modality is most difficult because of its high incidence of spontaneous wart resolution. The lesion can be cured even by hypnosis. Recently, the phenomenon of spontaneous regression of warts was reviewed from the viewpoint of tumor immunology. We now know that in the body, tumors may be rejected by an immune “surveillance” mechanism analogous to resistance to microbial pathogens. Various modalities of immunization procedure or enhancement of host immunity can induce partial or complete resolution of established tumors in both experimental animals and humans. Even malignant tumors, such as melanoma or choriocarcinoma, may disappear spontaneously. Wart is one of the most common tumors in humans and probably the tumor that most commonly shows the phenomenon of spontaneous regression. Advances in molecular biology and biotechnology have disclosed that, as there are various clinical types of wart, there are many distinct HPV types and that the distinct HPV types are associated with distinct cutaneous and mucosal papillomas. 1 Analogous to animals with the Shope papillomavirus or bovine papillomavirus infections, it is known that some human papillomavirus lesions may undergo malignant transformation. 2,3