Histological recurrence and depth of loop treatment of the cervix in women of reproductive age: incomplete excision versus adverse pregnancy outcome

Objective Recent meta-analyses have shown that loop treatment of the cervix of >10 mm depth may be associated with adverse outcomes in future pregnancies. The aim of this study is to assess the rate of incomplete excision and recurrent disease in relation to depth of excision in women of reproductive age undergoing loop treatment. Design Observational cohort study. Setting Colposcopy Clinic, Northern Gynaecological Oncology Centre, Gateshead, UK. Population In all, 1558 women undergoing loop treatment for high-grade cervical intraepithelial neoplasia (HGCIN) between 1998 and 2003. Methods Women were followed up until 2008. Recurrence was analysed using Kaplan-Meier plots. Outcome measures Incomplete excision rates and recurrence rates. Recurrence was defined as post-treatment disease with high-grade histology. Any dyskaryotic cytology on follow-up was also documented. Results Recurrent high-grade disease on histology was found in 57/1558 (3.7%) women. In women <= 35 years old, despite a greater rate of incomplete excision at the endocervical margin at loop depths <10 mm compared with >= 10 mm (24.4% versus 13.3%, P < 0.01), the recurrence rate was similar between the two groups (4.3% versus 3.4%, log-rank, P = 0.52). In contrast, a loop depth < 10 mm was associated with a higher disease recurrence rate (7.5% versus 3.0%, log-rank, P = 0.05) in women >35 years. Conclusion In women of reproductive age requiring treatment for HGCIN, colposcopists performing loop excision should aim for <10 mm depth. This provides adequate treatment for HGCIN and minimises the potential risk of adverse outcomes in future pregnancies.