Introduction/Background The incidence of vulvar high-grade squamous intraepithelial lesions (HSIL) is increasing. CO2 laser has gradually replaced surgical excision. More recently, off-label use of topical imiquimod is gaining popularity. Very little data compares these two treatment modalities. The main objective of our study was to compare the efficacy of CO2 laser with that of topical imiquimod as initial treatment for vulvar HSILs.

Methodology This retrospective cohort study included all patients first diagnosed with vulvar HSIL between 2017 and 2021, initially treated at a tertiary centre with CO2 laser therapy or topical imiquimod and who had at least one follow-up visit. Exclusion criteria included: pregnancy, recurrent disease, differentiated-type vulvar intraepithelial neoplasia or suspected or confirmed invasive disease. Primary outcome, i.e. ’cure’, was defined as no second treatment during the follow-up period. Occurrence of serious adverse events (emergency room visit, hospitalisation, prescription of narcotics or oral or IV antibiotics) was also noted.

Results A total of 52 women were included in the study. Participant characteristics were similar between the 2 treatment groups, laser (n=17) versus imiquimod (n=35): mean age 52.9 vs. 52.8 years (p= 0.97); active smoking: 41.2% vs. 40.0% (p= 0.94); immunosuppression: 5.9% vs. 8.6% (p=0.73). Mean follow-up time was slightly shorter in the laser group: 2.2 years vs. 2.8 years (p=0.12) in the imiquimod group. The proportion of cured participants was similar between the 2 groups: 47.1% in the laser group vs. 42.9% in the imiquimod group (p=0.77). No serious adverse events were noted.

Conclusion CO2 laser therapy and topical imiquimod showed a similar success in the treatment of a first HSIL of the vulva, and both appear safe. Given the lack of availability of the CO2 laser in many settings, the use of topical imiquimod could enable patients to be treated in their community, avoiding additional consultations and the associated inconvenience and costs.

Disclosures None