The significance of the histologic alterations adjacent to invasive vulvar carcinoma.

It has been superficially recognized, but not appreciated, that carcinoma of the vulva differs in many respects from carcinoma of the uterine cervix. Past studies have suggested that "leukoplakia and leukoplakia-like lesions" are probably premalignant conditions since they are commonly associated with invasive cancer. Conversely, studies of the dystrophies during the past 15 years have indicated that the latter uncommonly progress to invasive cancer if treated adequately. In an attempt to review the histopathologic changes associated with invasive cancer, the last 98 cases of invasive disease were studied and the histopathologic characteristics of the adjacent tissue were divided into categories. It was noted that less than 20% of the invasive cancers demonstrated classic in situ neoplasia in the adjacent area, whereas more than 50% showed patterns suggestive of the dystrophies. Thus, although the dystrophies were not necessarily the precursory lesions, they did demonstrate probable long-term irritation, which is of major importance in the genesis of vulvar cancer. Furthermore, in situ cancer, as seen in the young patient, rarely seems to progress to invasive disease.