Loop diathermy excision compared with cervical laser vaporisation for the treatment of intraepithelial neoplasia: a randomised controlled trial

Objective To determine whether loop diathermy excision of the. transformation zone and laser vaporisation are equally effective in the treatment of cervical intraepithelial neoplasia. Design Randomised controlled trial. Population Women referred for evaluation of cytological abnormality who were considered suitable for outpatient local destructive treatment. Setting Seven colposcopy units in the North West Region. Methods Loop diathermy excision of the transformation zone and laser vaporisation. Main outcome measure Smear reported as moderate dyskariosis or worse following treatment. Results Of 289 women randomised, 285 had one or more smears following treatment. Women were more likely to have a smear reported as moderate dyskariosis or worse following laser vaporisation [hazard ratio 3.01 (95% CI 1.27 to 7.12)]. The cumulative risk of a smear reported as moderate dyskariosis or worse was 6.0% at six months and 12.1% at three years in those allocated laser vaporisation, and 2.0% at six months, and 3.3% at three years in those allocated loop diathermy excision of the transformation zone. Conclusions Loop diathermy excision is a more effective treatment of cervical intraepithelial neoplasia than laser vaporisation.