Nonhormone therapies
Topical lidocaine for insertional dyspareunia has been studied in postmenopausal women with breast cancer with severe GSM, dyspareunia, increased sexual distress scores, or abnormal sexual function with improvement seen using 4% aqueous lidocaine versus saline applied with a cotton ball to the vestibule for 3 minutes before vaginal penetration.9
Vaginal laser therapy has the potential to ameliorate distressing GSM without the need for local hormone intervention; however, placebo or active-controlled trials and long-term safety follow-up are needed.5
Newly arrived and on the horizon
Where does this review of available treatments leave us? Regrettably, with many women who experience painful intercourse and vaginal dryness despite what is available for treating their problems, and who continue looking to medical science and women’s health care for new options. So, what is coming next for these suffering patients? Here is a quick and selective run-through:
KNDy neurons. For hot flashes, there is the promise of nonhormonal treatment using these neurons, believed to be involved in reproduction by triggering expression of various compounds— particularly neurokinin B, which mediates hot flashes.1
Estetrol. In testing for use in treating hot flashes and its effect on GSM is this pregnancy-associated natural hormone that, importantly, did not stimulate breast cancer in a rat model.2 More evidence of efficacy is needed.
Lasers. For vaginal atrophy, many women are choosing treatment with the laser. Keep in mind, however, that, although lasers are FDA-approved devices, they do not have the FDA’s endorsement for use in vaginal atrophy, and have not been well-tested for their effectiveness for this indication in women with breast cancer who have taken an aromatase inhibitor. ACOG, NAMS, and the Endocrine Society have urged that additional trials be conducted, and have stated that the laser for vaginal atrophy cannot be recommended until there are more data on safety and efficacy.2
Lower-dose soft-gel vaginal estrogen suppositories have recently been approved by the FDA at 4 and 10 µg.3 The formulations are only minimally absorbed, potentially making them a good option for women who have had breast cancer.
Lasofoxifene, a selective estrogen-receptor modulator not yet approved by the FDA, has been shown to ameliorate vaginal changes.4 The drug is neutral or protective on the breast, but is now being tested in women with resistant breast cancer and unlikely to become available for GSM.
References
1. Anderson RA, Skorupskaite K, Sassarini J. The neurokinin B pathway in the treatment of menopausal hot flushes. Climacteric. 2018;1-4.
2. Gérard C, Mestdagt M, Tskitishvili E, et al. Combined estrogenic and anti-estrogenic properties of estetrol on breast cancer may provide a safe therapeutic window for the treatment of menopausal symptoms. Oncotarget. 2015;6(19):17621–17636.
3. Simon JA, Archer DF, Constantine GD, et al. A vaginal estradiol softgel capsule, TX-004HR, has negligible to very low systemic absorption of estradiol: efficacy and pharmacokinetic data review. Maturitas. 2017;99:51-58.
4. Bachmann G, Gass M, Kagan R, et al. Lasofoxifene (LASO), a next generation selective estrogen response modulator (SERM), improves dyspareunia in postmenopausal women with vaginal atrophy (VA). Menopause. 2005;12:238.
Treatment begins with a conversation
Most importantly, we need to listen to our patients in discomfort because of their menopausal symptoms. Consider proceeding along these lines: “You’ve been treated for breast cancer; now, let’s look at the medical issues that are affecting your quality of life. Are you depressed? Are you having hot flashes? Are you getting enough sleep? Have you stopped having sex or not restarted after your breast cancer treatment? Are you having painful sex or avoiding sex due to fear of pain? Let’s discuss options and work with your oncologist to try to relieve your symptoms and make your life better.”
First-line therapy for the treatment of menopausal symptoms in women with a history of breast cancer should start with lifestyle changes and nonhormone therapies. For GSM, lubricants and vaginal moisturizers should be tried first and may be effective. Reassure patients that there are many treatment options, even though not all of them have been well-tested in breast cancer patients, and that new modalities are under investigation and review (see “Newly arrived and on the horizon,”). Become familiar with published data on the safety and effectiveness of the range of available treatments; guide patients through the process of finding what works best for them; and invite their oncologist into the therapeutic partnership. If you do not feel comfortable with these issues in women who are breast cancer survivors, find a menopause specialist to help, available by zip code at Find a Provider, http://www.menopause.org.