Objective: To assess the effectiveness of cone biopsy, cryotherapy, laser a
blation and the loop electrosurgical procedure in the treatment of squamous
intraepithelial lesions. Method: Systematic review of randomized controlle
d trials in subjects who underwent treatment of low- and high-grade squamou
s intraepithelial lesions with these modalities. Main outcome measures incl
uded the following: percent resolution and persistence of a lesion and nota
ble complications for each procedure. Result: Pooled rates of resolution fo
r low-grade, high-grade, or combined squamous intraepithelial lesions were
similar across the different treatment modalities (range 85.2-94.7%), with
substantial overlap among the 95% confidence intervals. Significant hemorrh
age occurred most frequently in subjects who received cone biopsy (4.6%) (9
5% CI: 2.15, 6.99), followed by laser ablation (1.75%) (95% CI: 0.70, 2.81)
, and LEEP (1.35%) (95% CI: 0.24, 2.47). No hemorrhages were reported among
subjects who received cryotherapy. Study sample sizes were relatively smal
l. There were no reported cases of progression to invasive cancer, but dura
tion of follow-up (median follow-up time for all eligible studies = 12 mont
hs) was not sufficient to evaluate long-term outcomes. Conclusions: There w
ere no substantive differences in outcomes regarding persistence and resolu
tion in the treatment of squamous intraepithelial lesions for subjects rece
iving cone biopsy, cryotherapy, laser ablation, or LEEP. (C) 2000 Internati
onal Federation of Gynecology and Obstetrics.