Positive predictive rate of colposcopic examination of the cervix uteri: an overview of literature.

Study of literature revealed that the positive predictive rate of the colposcopic impression is better as the cervical lesion is more severe. When directed biopsies are taken, the positive predictive rate of colposcopy increases considerably. For microinvasive disease, the positive predictive rate is quite poor, probably because of the absence of characteristic features. Large loop biopsies diagnosed all cases of microinvasive disease missed by directed biopsies, but this technique has the disadvantage of considerable "overtreatment" when integrated in the management of all patients with abnormal cytology. The restrictions of colposcopy are the invisibility of the squamocolumnar junction and observer variability in the assessment of the impression. The levels of agreement among experienced colposcopists are in the same range as those in cytological and histopathological diagnosis. It is concluded that colposcopy is an indispensable tool in the management of premalignant cervical disease, as long as the restrictions of the technique are kept in mind by the colposcopist.