Vaginal Estrogen Therapy Does Not Increase Risk of Death in Breast Cancer Patients

Vaginal estrogen therapy does not increase the risk of death in patients with breast cancer, according to research published in JAMA Oncology.

In fact, researchers found modest decreases in the risk of breast cancer-specific death and all-cause death among patients who used vaginal estrogen therapy.

In this population-based study, researchers examined data from national cancer registries in Scotland and Wales for 49,237 women diagnosed with breast cancer between the ages of 40 and 79 years.

After breast cancer diagnosis, 5% of patients used vaginal estrogen therapy, and 1% received systemic hormone replacement therapy (HRT).

There were 5795 breast cancer-specific deaths at a median follow-up of 5 years in the Scotland cohort and 8 years in the Wales cohort.

In an adjusted analysis, there was a modest decrease in the risk of breast cancer-specific death among patients who used vaginal estrogen therapy (hazard ratio [HR], 0.77; 95% CI, 0.63-0.94; P =.01).

Results were similar whether patients received 1-4 vaginal estrogen therapy prescriptions (HR, 0.81; 95% CI, 0.67-0.99; P =.04) or 5 or more prescriptions (HR, 0.57; 95% CI, 0.34-0.96; P =.03).

There was no significant association with lower-dose vaginal estrogen therapy (HR, 0.77; 95% CI, 0.56-1.07; P =.12) or higher-dose therapy (HR, 0.81; 95% CI, 0.55-1.21; P =.31).

The researchers also found no significant association between systemic HRT use and breast cancer-specific death (HR, 0.98; 95% CI, 0.68-1.40; P =.90).

Likewise, there was no significant association between vaginal estrogen use and cardiovascular death (aHR, 0.78; 95% CI, 0.28-2.16), but there was a modest decrease in the risk of all-cause death among vaginal estrogen users (aHR, 0.80; 95% CI, 0.71-0.90).

These findings “may provide some reassurance to prescribing clinicians and support the guidelines suggesting that vaginal estrogen therapy can be considered in patients with breast cancer and genitourinary symptoms if nonhormonal treatments are unsuccessful,” the researchers concluded.

Disclosures: One of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.

Reference

McVicker L, Labeit AM, Coupland CAC, et al. Vaginal estrogen therapy use and survival in females with breast cancer. JAMA Oncol. Published online November 2, 2023. doi:10.1001/jamaoncol.2023.4508

This article originally appeared on Cancer Therapy Advisor