A review of the recent literature regarding malignant transformation of oral lichen planus.

On the basis of a literature review of the period 1950-1976, Krutchkoff et al questioned the possible premalignant nature of oral lichen planus. Their criticism was largely based on insufficiencies of data in support of the initial diagnoses of the condition. In this article, a review of the literature from the period 1977-1999 has been described; the criteria used were those of Krutchkoff et al. Thirty-three (34%) of 98 reported cases were accepted as having sufficiently documented evidence of malignant transformation of oral lichen planus. Although this percentage is somewhat higher than the percentage reported by Krutchkoff et al, there apparently remains a need for uniformly accepted criteria to establish a firm diagnosis of oral lichen planus. Only when such criteria are available will it be possible to conduct long-term prospective studies on the suggested possible premalignant nature of oral lichen planus.