Comparison between Single Versus Twice Application of Topical 85% Trichloroacetic Acid in the Treatment of Cervical Intraepithelial Neoplasia; A Randomized Clinical Trial on Efficacy and Tolerability

PURPOSE: To compare the efficacy and safety of up to two-time administration of 85% TCA, as a promising alternative therapy to conservative and surgical management of grade one to three CINs. METHODS: In this two-armed randomized clinical trial, a total of 53 patients with biopsy-proven CIN lesions were allocated to two groups of TCA treatment. The first group (n=26) received a single dose of local therapy with 85% TCA while the second group (n=27) was treated on two separate occasions with a two-week interval. Two participants (one in each group) were lost to follow-up. At the two-month follow-up after TCA application, a colposcopy-guided biopsy was performed for all patients and the pathological specimens were studied by a single experienced pathologist to determine the post-intervention grading of CIN. RESULTS: Two groups were comparable in terms of age and base-line lesion grading, as CIN 1 lesions comprised the majority of cases (54%), followed by CIN 2(37%). While our sample was a poor representative of CIN3 lesions (7%), no significant difference was noticed between the single and twice TCA treated groups with a response rate of 52% and 54% respectively (either complete remission to normal histology or regression to any low-grade lesion). Either separate analysis (with respect to the base-line grading within each treatment group) or combined analysis (regardless of CIN sub-group) could not generate any statistical significance. The second dose of TCA did not increase the frequency of reported adverse events. CONCLUSION: The second dose of topical 85% TCA does not seem to increase the CIN response rate more so than its single dose. However, further controlled clinical trials with larger samples are warranted to verify current findings. The use of TCA was not limited by any major side effect, therefore, the potential to achieve an increased efficacy with more frequent TCA applications is appealing.