This study used 2 different methods, fractional Carbon Dioxide laser and electrostimulation of smooth muscle, to treat non-neoplastic epithelial disorders of the vulva and compared their clinical efficacies. The PGI-C scores showed that 3, 6 and 12 months after the completion of treatment, subjective improvement in the laser treatment group was better than that in the electrostimulation group. This result is in agreement with the results reported by Lee et al. and Stuart et al. Lee et al. performed fractional Carbon Dioxide laser therapy on 4 patients with vulvar lichen sclerosus, for whom corticosteroid treatments were ineffective, and the subjective symptoms improved in all 4 patients after treatment. In addition, they found that Carbon Dioxide is very effective in inhibiting hyperkeratosis in clinical practice (7). Stuart et al. reported that 6 out of 7 patients with vulvar lichen sclerosus, who did not respond to other treatments, were asymptomatic after laser ablation(8). In 2011, Gaspar et al. reported a controlled study of 40 cases of non-neoplastic epithelial disorders of the vulva treated by fractional Carbon Dioxide laser. The results showed that symptoms such as pruritus vulvae and intercourse pain were significantly mitigated, and no adverse events occurred (9). This may be related to the thermal effect of the laser, which causes tissue oedema and the release heat-shock protein 70 and transforming growth factors and promotes fibroblast proliferation and the synthesis of extracellular matrices such as collagen and proteoglycan, thereby restoring tissue elasticity, initiating vascular reconstruction and increasing blood flow (10). As a result, the blood supply to and nutrition for the skin improved in the 2 lichen-like lesions of the vulva, the local scratched and damaged tissues were repaired, the integrity and elasticity of the vulvar skin were maintained, and local resistance to the outside environment was enhanced. Our study also showed that the total effective rates for both treatment regimens were more than 50.00% 3, 6, and 12 months after the completion of treatment; in the laser treatment group, clinical efficacy was most pronounced and was stable for a long period, and the total effective rate reached 90.00% 3 months after the completion of treatment and stabilized at 85.00% 6 and 12 months after the completion of treatment. This result is similar to that reported by Peterson et al. (11), who found that patients with vulvar lichen sclerosus treated with Carbon Dioxide laser had normal epithelium in regenerated vulvar tissue and that if no further treatment was provided, the symptoms lasted longer (2–3 years).
This study also showed that electrostimulation also had a good effect in the treatment of non-neoplastic epithelial disorders of the vulva, which may be related to the pathogenic mechanism of non-neoplastic epithelial disorders of the vulva. Studies have shown that the major ultrastructural changes in non-neoplastic epithelial disorders of the vulva are characterized by the narrowing and stenosis of intradermal capillary lumens, the widening of gaps between cells, and the reduction in desmosomes and melanin granules (12). The low resistance caused by microcirculatory disorders that are triggered by cellular energy and material metabolism disorders may result in secondary local inflammation, while inflammatory mediators stimulate the peripheral nerves to cause pruritus vulvae and repeated scratching further aggravates skin lesions, thus forming a vicious cycle (13, 14). Electrostimulation of vascular smooth muscle can electrically stimulate vascular smooth muscle, improve the local microcirculation of vulvar skin, local vulvar lymph circulation reflux, local microcirculation and microenvironment, and tissue repair ability, thereby restoring the immune function of the vulva, improving hormone receptors and sensitivity, and further improving the symptoms and physical signs of patients with lichen simplex chronicus and lichen sclerosus.
More importantly, the results of this study showed that different pathological types showed different responses to different therapeutic methods. Whether subjective improvement or clinical efficacy was compared, lichen simplex chronicus showed a better response to both electrostimulation and laser treatment than did lichen sclerosus, indicating that the pathogenesis and molecular biology of lichen simplex chronicus and lichen sclerosus may be different (15). However, causes for different treatment responses of different pathological types may require further investigation.
This study has the following limitations. (1) Although compared with existing reports the sample size of our study was not too small, a larger sample size could better reduce the selectivity bias. (2) A multicentre randomized controlled study is needed to provide better evidence for clinical treatment decision-making. (3) A longer follow-up time could further validate the long-term efficacy of different therapeutic methods.
In summary, compared with electrostimulation, fractional Carbon Dioxide laser treatment resulted in better PGI-C scores and clinical efficacy and better long-term stability in patients with non-neoplastic epithelial disorders of the vulva. In addition, for different pathological subtypes of non-neoplastic epithelial disorders of the vulva, the treatment efficacy for lichen simplex chronicus was higher than that for lichen sclerosus. Therefore, for patients with poor response to electrostimulation, fractional Carbon Dioxide laser treatment can be used as a new therapeutic option for non-neoplastic epithelial disorders of the vulva.