A review of the treatment failures following cervical intraepithelial neoplasia grade III treated by large loop excision of the transformation zone.

The records of 208 women were reviewed to quantify the long-term treatment failures of large loop excision of the transformation zone (LLETZ) in the treatment of cervical intraepithelial neoplasia (CIN) grade III. The rate of dyskariotic smears fell from 8% at 6 months to 2.3% at 48 months. The excision was considered incomplete in 84 cases (40.3%) of which 40 had endocervical margins involved. Thirty-five per cent of women with incomplete excision of CIN at the endocervical margin and 9% with complete excision had a dyskariotic smear within 4 years following LLETZ. These findings were statistically significant (P = 0.003 and 0.02 respectively). However, 5% only of women in the former group had cytological treatment failure at 6 months. There was no significant association between age and incidence of treatment failure. Further data are required to determine the risk of recurrence beyond 4 years before recommendations could be made about the duration of annual screening.