The value of colposcopy in screening cervical carcinoma

The value of colposcopy and cytology in screening CIN was analyzed in a retrospective study of 1,504 patients treated at the Department of Gynecologic Oncology, National Institute of Oncology, Budapest from 1980 to 1991. The majority (1,451) of the patients were admitted for histological confirmation of atypical colposcopic and/or cytologic findings, and 53 women were treated for cervical repair. All women underwent either cervical excision or conization. Cytologic and colposcopic findings were compared with the histological results. Sensitivity and specificity rates of cytology were 47% and 77%, respectively. The corresponding figures for colposcopy were 87% and 15%, and for cytology and colposcopy together, 96% and 14%. The low sensitivity of cytology suggests that as many as 50% of CIN lesions may be overlooked if cytology alone is used for screening, i.e. in 50% of CIN associated with abnormal colposcopy the cytology was negative. We found 194 asymptomatic patients with carcinoma in situ, 40 with microinvasive and 8 with frank invasive carcinoma. This finding emphasizes the importance of cervical cancer screening. Our data suggest that, with colposcopy as a screening tool, the rate of false-negative cytology can be significantly reduced. Clinical implications of the "cytology-negative abnormal colposcopy and cytology-negative CIN" have yet to be determined. The major drawback of primary colposcopy is its low specificity with the consequence of high false-positive rate and over-treatment in a substantial number of cases. To overcome the problem of low specificity, further studies are required to identify those atypical colposcopic changes that most likely represent CIN- and high-grade CIN in particular.