DYSPLASIA

Dysplasia is characterized by deranged cell growth of a spe­cific tissue that results in cells that vary in size, shape, and organization. Minor degrees of dysplasia are associated with chronic irritation or inflammation. The pattern is most fre­quently encountered in areas of metaplastic squamous epi­thelium of the respiratory tract and uterine cervix. Although dysplasia is abnormal, it is adaptive in that it is potentially reversible after the irritating cause has been removed. Dys­plasia is strongly implicated as a precursor of cancer. In can­cers of the respiratory tract and the uterine cervix, dysplastic changes have been found adjacent to the foci of cancerous transformation. Through the use of the Papanicolaou (Pap) test, it has been documented that cancer of the uterine cervix develops in a series of incremental epithelial changes ranging from severe dysplasia to invasive cancer. However, dysplasia is an adaptive process and as such does not neces­sarily lead to cancer. In many cases, the dysplastic cells re­vert to their former structure and function