Conization for cervical dysplasia and carcinoma in situ: long term follow-up of 1013 women.

1013 women were treated with cold knife conization. Histopathological investigation of the cone biopsies revealed 169 with dysplasia, 718 with carcinoma in situ (CIS) and 26 with invasive carcinoma. Invasive carcinomas were found even in patients with the lowest degree of cytological abnormality. In 100 cases, no pathological changes were found. The majority of patients were followed for more than five years after conization. The longest period of follow-up was 17 years. In 98% of the women with various degrees of cervical dysplasia (including all severe dysplasias) the cytology returned to normal after conization. The corresponding figure for women with CIS was 90%. This figure depended on whether the resection margins of the cone were free from pathological epithelium. If they were free, 92% of the women had normal cytology at follow-up. However, if the margins were doubtful, the cytology returned to normal in 64%. All patients with marginal growth had a pathologic smear at follow-up. Most abnormal smears developed within the first year. If smears were negative the first year after conization for CIS with free margins of resection, the risk of developing severe dysplasia or CIS was 2.3%.