Test of cure and beyond: superiority of thermal ablation over LLETZ in the treatment of high-grade CIN

PURPOSE: Among the treatment modalities for high-grade cervical intraepithelial neoplasia (CIN), large-loop excision of the transformation zone (LLETZ) is the commonest offered in the UK, whereas thermal ablation (TA) has not been common in several decades, despite several notable advantages. TA and LLETZ are both routinely undertaken in our colposcopy unit, and extensive follow-up data have been used to interrogate outcomes between the two modalities and determine whether one modality may be preferred over the other. METHODS: Up to 8 years of follow-up data (cytology and histology) were collected for patients who have undergone LLETZ or TA and failed post-treatment test of cure (ToC). These data were analysed and used to plot Kaplan–Meier survival curves, in order to compare outcomes: negative cytology, dyskaryosis, low- and high-grade CIN and invasive squamous cell carcinoma. RESULTS: i) Very few women treated with TA developed recurrent high-grade CIN in the follow-up period; (ii) LLETZ-treated women had a significantly higher rate of recurrence than those treated by TA; (iii) women who failed both virology and cytology components of post-treatment ToC had higher recurrence than those who failed only one, and the rate of recurrence was highest in those treated by LLETZ (> 65%). CONCLUSION: TA is an effective treatment of high-grade CIN, with a high chance of achieving double-negative ToC and low recurrence relative to LLETZ. We recommend the wider adoption of TA, so that young women of reproductive age have a choice of treatment with no reported adverse effects on pregnancy outcomes.