Clinical and laboratory results in vaginal wall restoration using a fractional-pixel-CO2 laser: histological findings and changes in the Ki67 protein and telomere length.

Abstract

Thermal deposition of laser energy in the vaginal epithelium in genitourinary syndrome of menopause (GSM) results in clinical and biological effects, but many cellular and molecular changes indicating cell proliferation or senescence inhibition are unknown. The aim of this study is to evaluate the clinical efficacy of the fractional-pixel-CO2 laser in the possible improvement of GMS signs and symptoms that can be correlated with histological changes or with cellular or molecular indicators of restoration. A detailed prospective study was designed to assess 17 women diagnosed with GSM who were treated intravaginally with two laser sessions. Seven non-treated women diagnosed with GSM were used as controls. Three validated outcome questionnaires for assessment of quality of sexual life and urinary incontinence were performed. Vaginal biopsies were collected before the first laser treatment and 4months following the second session. Histological status, elastin, collagen, and hyaluronic acid content of the biopsies were also evaluated. Cell proliferation was assessed by Ki67 staining. Telomere length (TL) was measured by qPCR. The results show an improvement of the clinical symptoms of GSM (p < 0.05), vaginal epithelium recovery and enhancement of collagen (p < 0.05), elastic fibers (p < 0.005), and hyaluronic acid (p < 0.0005) content in the lamina propria after fractional-pixel-CO2 laser treatment. The laser treatment induced a significant rise on the TL of vaginal epithelial cells (VECs), and a positive correlation was found between the improvements of the collagen and hyaluronic acid content and TL changes (r = 0.82, p < 0.05; r = 0.38, p < 0.05). The percentage of proliferative Ki67-positive VECs was increased in patients whose vaginal TL lengthened after laser treatment (p < 0.05). In conclusion, the results indicate that laser treatment may induce restoration of the vaginal epithelium which is associated to increased TL and proliferation in the VECs. Performing a TL assay could be a suitable tool to evaluate the efficacy of vaginal laser treatment.