OBJECTIVE.: Our objective was to compare by response rate the therapeutic options of loop electrosurgical excision procedure (LEEP), laser therapy, and wide local excision in managing high-grade vulvar intraepithelial neoplasia in a pilot study for a randomized clinical trial. MATERIALS AND METHODS.: Between 1995 and 1999, 109 patients presenting with vulvar lesions were registered at a comprehensive cancer center and 2 associated colposcopy clinics. From these 109, we identified 74 patients with lesions histologically proven to be vulvar intraepithelial neoplasia who underwent treatment with CO2 laser, wide local excision, or LEEP. Clinical and pathological features were reviewed retrospectively. Wilcoxon rank sum test and life table analyses were used to compare groups. Response rates for this retrospective study will be used to calculate the sample size for a prospective clinical trial. RESULTS.: Our population was similar to others reported in the literature in age, range of diagnoses, and follow-up. Only 1 of 74 patients (1%) had invasive cancer. In a subset of 62 patients treated for the first time, LEEP and wide local excision were equal in their ability to achieve complete response. Laser ablation was the least successful of all methods (10/20 with laser, 3/20 with LEEP, and 2/22 with wide local excision experienced recurrences [p = .04]). No statistically significant differences among the 3 were noted in time to recurrence (p = .24). Age, age at first intercourse, and number of sexual partners were not correlated with recurrence and did not confound the results. Using a chi approximation, an alpha error of 0.05, and a power of 0.80, researchers should enroll 25 patients per arm if improvement over standard therapy is expected to be 40%, 45 if expected to be 30%, and 95 if expected to be 20%. CONCLUSIONS.: Because of differences in recurrence rate and length of hospital stay and indications of potential differences in cost found in this pilot, LEEP merits comparison in a prospective randomized clinical trial with wide local excision and laser therapy in which recurrence rate, patient treatment preference, and cost-effectiveness are evaluated. Patients entered in such a trial should be stratified according to their risk of invasion. If the risk of invasion is high, then the laser should be used to excise a sample rather than ablate.