Invasive cancer after treatment of cervical intraepithelial neoplasia.

This review discusses the risk of invasive cancer following treatment for cervical intraepithelial neoplasia (CIN). The emphasis is on methods in current use and the risks are calculated with life table methods. Large, long-term follow up studies which use life table analysis show clearly that invasive recurrences continue to appear at a relatively steady rate for at least 8 years after treatment for CIN. The risk remains 4 to 5 times greater than in the background population throughout this period. It would seem prudent to continue to offer these women increased surveillance with annual smears during this time of increased risk. All modern methods of outpatient treatment are highly effective in preventing invasive cancer of the cervix if they are used skillfully with an understanding of the disease being treated. The thoughtless use of beguilingly easy methods will lead only to disaster.