False positive cervical cytology: an important reason for colposcopy

Over an 18 month period, 352 patients with a report of abnormal cervical cytology ranging from mild dysplasia to invasive carcinoma were evaluated with colposcopy and, if indicated, directed biopsies. From the group, there were 26 women in which a lesion consistent with the cytologic diagnosis was not found in each of these cases, an error in the interpretation of the Papanicolaou smear, resulting in a false positive report, was suspected. The cytology was reviewed and the results were compared to the original reports. Twelve cases were reinterpreted as negative for cervical neoplasia. A similar review of the histology failed to reveal a previously missed lesion. Cervical conization in four patients and repeat cytology and colposcopy in 22 patients confirmed the false positive interpretations of the original cervical cytology. The importance of colposcopy as a means of recognizing false positive cytology and avoiding an unnecessary cervical conization is emphasized.