Meta-analysis of cold-knife conization versus loop electrosurgical excision procedure for cervical intraepithelial neoplasia

Objective: This meta-analysis aimed to compare the superiority of loop electrosurgical excision procedure (LEEP) or large loop excision of the transformation zone (LLETZ) versus cold-knife conization (CKC) in the surgical treatment of cervical intraepithelial neoplasia (CIN). Methods: Systematic searches were performed in the MEDLINE, EMBASE, Cochrane databases, and the China National Knowledge Infrastructure Databases to identify all potential articles involving patients with CIN treated with LEEP/LLETZ or CKC published up to February 2016. Risk ratios (RRs) or weighted mean difference (MD) with a 95% confidence interval (95% CI) were calculated. Results: Seven randomized controlled trials, one prospective cohort study, and twelve retrospective cohort studies were included in this meta-analysis. There were no significant differences following LEEP/LLETZ compared with CKC in recurrence rate (RR = 1.75, 95% CI = 0.99-3.11, P=0.06), positive margin rate (RR = 1.45; 95% CI = 0.85-2.49, P=0.17), residual disease rate (RR = 1.15, 95% CI = 0.73-1.81, P=0.48), secondary hemorrhage (RR = 1.16, 95% CI = 0.74-1.81; P=0.46), or cervical stenosis. Moreover, subgroup analyses based on randomized trials also revealed that no statistical significance was observed in the above outcomes. However, women treated with CKC had a significantly deeper cervical cone than those treated with LLETZ/LEEP (MD=-5.71, 95% CI=-7.45 to -3.96; P < 0.001). Conclusion: LEEP/LLETZ is as effective as CKC with regard to recurrence rate, positive margin rate, residual disease rate, secondary hemorrhage, and cervical stenosis for the surgical treatment of CIN. Further large-scale studies are needed to confirm our findings.