Vaginal Testosterone Cream vs Estradiol Vaginal Ring for Vaginal Dryness or Decreased Libido in Women Receiving Aromatase Inhibitors for Early-Stage Breast Cancer: A Randomized Clinical Trial

Authors: Melisko, M.E., et. al.

Source: JAMA Oncol, doi:10.1001/jamaoncol.2016.3904

jamanetwork.com/journals/jamaoncology/article-abstract/2580714

Postmenopausal women are usually placed on aromatase inhibitors (AIs) following initial treatment of hormone receptor-positive breast cancer. These medications work by blocking the production of estrogen. While that effect is very beneficial in reducing cancer recurrence and improving survival, it may also cause vaginal dryness, painful sexual intercourse (dyspareunia) and decreased libido.

Studies have looked into different hormone preparations that may be useful and safe for this group of women. The investigators followed 68 women who were randomized to either an estradiol-releasing vaginal ring (ring) or intravaginal testosterone cream (IVT). Baseline estradiol (estrogen) levels were measured before starting the therapy, and then 4 and 12 weeks later.

Both treatment groups had transient elevations in estrogen levels.  For most patients, the estrogen levels dropped to normal ranges at the follow up measurements. The elevations seen were within the ranges of safety.

Physical examinations revealed that signs of vaginal atrophy diminished significantly in both groups after 12 weeks of treatment. Moreover, women reported significant improvements in sexual interest and sexual function after 12 weeks of treatment.

This study shows that these two vaginal preparations improved sexual function and interest and relieved vaginal discomfort in postmenopausal women receiving AIs for breast cancer therapy. While there is concern that such treatment will elevate estrogen levels, this work showed that the elevations were transient, suggesting that this treatment is safe for this subset of women with breast cancer. The investigators recommend continued study of the long term effects of such vaginal preparations, and that women receiving them have their estrogen and testosterone levels checked regularly.