Meta-analysis of the effectiveness of cryotherapy in the treatment of cervical intraepithelial neoplasia

Abstract Background Cryotherapy can be used for the ablation of cervical intraepithelial neoplasia (CIN). Objectives To provide an updated and comprehensive estimate of the efficacy of cryotherapy for CIN. Search strategy A literature search identified original studies (randomized controlled trials and clinical reports). Selection criteria Studies reporting cure rates, acceptability, and safety of cryotherapy were included in the analysis. Data collection and analysis Number of persistent or recurrent lesions at follow-up, adverse events, and complications were recorded. Quality of the methodology was also assessed. Meta-analyses were performed according to CIN thresholds, geographic region, study year, setting, study design, presence of endocervical involvement, freezing method, duration of follow-up, and status of the cryotherapy provider. Main results A total of 146 articles were retrieved; 77 papers—equivalent to 28 827 cases of treated CIN—were included in the meta-analysis. Cryotherapy achieved cure rates of 94.0% (CIN1), 92.0% (CIN2), and 85.0% (CIN3). Use of the double-freeze method and absence of endocervical involvement significantly increased cure rates. Minimal complications were reported as adverse effects. Conclusions Cryotherapy is an effective, safe, and acceptable treatment for CIN. It has been shown to be successful in low-resource settings, enabling availability and accessibility of early detection services.