CO₂ Laser Therapy for Genitourinary Syndrome of Menopause in Women with Breast Cancer: A Randomized, Sham-Controlled Trial

Objectives: We aimed to study the efficacy of fractional CO₂ laser for genitourinary syndrome of menopause (GSM) symptoms in breast cancer (BC) survivors through a randomized, sham-controlled study, followed by an open-phase study assessing the impact of additional treatments. Methods: BC survivors with GSM were randomized to receive either three sessions of intravaginal CO₂ laser or sham treatment every 3–4 weeks. The laser’s energy was 45–60 mJ/pixel. Outcomes were compared one month following the last session. Participants initially receiving laser treatment were offered three more sessions, while those receiving sham had six laser sessions in an open-label study. Results: Thirty-four BC survivors were randomized to laser (n = 19) or sham (n = 15) treatments. Dyspareunia and intercourse dryness scores improved in both groups one month post-treatment, without a significant advantage of laser over sham. The laser treatment resulted in a reduction in daily dryness (−1.30 ± 0.55, p = 0.017), an increase in vaginal hydration (3.24 ± 1.13, p = 0.004), and an increase in Vaginal Health Index (VHI) (2.26 ± 0.50, p < 0.001). Most participants (18/19 and 9/15, respectively) opted to continue laser treatments after unblinding, resulting in 27 patients receiving six laser treatments. Increasing the number of laser treatments was associated with a constant improvement in Visual Analogue Score (VAS) scores for dyspareunia, intercourse dryness, daily dryness, burning, discomfort, itch, and average VAS, as well as pH, VHI, and hydration. Conclusions Three fractional CO₂ laser treatments for BC survivors reduced daily dryness but did not improve dyspareunia and sexual dryness when compared to sham in this randomized trial. Increasing the number of treatment sessions seemed to improve outcomes; however, it remained clinically insufficient, even after six treatments.