Impact of colposcopy-guided carbon dioxide laser vaporization therapy on peripheral cervical intraepithelial neoplasia lesions

Objective: Laser vaporization is less invasive than conization for cervical intraepithelial neoplasia (CIN). The outcome of laser vaporization for CIN is empirically known to depend on the colposcopic findings, especially localization of the lesion. In this study, we sought to identify factors involved in the outcome of laser vaporization.

Materials and methods: We retrospectively investigated 290 cases of CIN (CIN2, n = 180; CIN3, n = 110) treated with laser evaporation at Nishikawa Women's Health Clinic between 2018 and 2021. All treatments were performed using a carbon dioxide laser under either colposcopic vision (n = 172) or direct vision using a vaginal speculum (n = 118). Risk factors were statistically examined for cure rate after treatment.

Results: Multivariate analysis using a logistic regression model identified independent factors affecting the success of treatment to be high-risk human papillomavirus infection status preoperatively, CIN grade, presence of CIN lesions at the periphery of the cervix, and the surgical method used. Colposcopy-guided laser vaporization reduced the risk of treatment failure by 84% (odds ratio 0.16, 95% confidence interval 0.06-0.46; p = 0.001) compared with direct vision using a vaginal speculum. For lesions at the periphery of the cervix, most of the treatment failures were in the group that was not guided by colposcopy (p = 0.031).

Conclusion: The presence of a peripheral CIN lesion was suggested to be a risk factor for treatment failure. Laser vaporization under colposcopic vision is recommended for treatment of peripheral CIN lesions.