TOPLINE: 

In a retrospective study, endometrial cancer survivors who were prescribed vaginal estrogen therapy for a limited time were not at increased risk for recurrence, though use of the therapy was low overall.

METHODOLOGY:

• Endometrial cancer survivors who enter early menopause following surgery often experience genitourinary symptoms such as vaginal dryness, urinary problems, and dyspareunia. Vaginal estrogen therapy can help ease those symptoms, with minimal systemic absorption, but evidence on the safety of such therapy after endometrial cancer is limited.
• To investigate, researchers analyzed electronic health records from the TriNetX US Collaborative Network, which includes data from 68 US healthcare organizations. They identified 25,408 women aged 18-51 years diagnosed with endometrial cancer between November 2005 and December 2023.
• The investigators used 1:1 propensity score matching to create two cohorts of 1412 women each, with and without vaginal estrogen therapy use in the year after endometrial cancer diagnosis. The groups were matched on baseline characteristics including age, race, ethnicity, BMI, comorbidities, and healthcare use. The average estrogen therapy duration was just under 2 years.
• The primary outcome was endometrial cancer recurrence, defined as a debulking procedure, radiotherapy, chemotherapy, immunotherapy, or other relevant medication occurring 1 year or more after diagnosis, assessed during years 1 to 6 post-diagnosis.

TAKEAWAY:

• Overall, recurrence risk was not significantly different between the two groups (HR, 0.87; 95% CI, 0.60-1.27), with 53 women in the estrogen therapy group and 54 women in the comparator group experiencing recurrence.
• Before matching, only 1412 of 25,408 endometrial cancer survivors (5.6%) had two or more prescriptions for vaginal estrogen within 1 year of diagnosis, indicating minimal utilization of the therapy.
• In a negative control analysis, there was a difference in flu vaccination between the two groups (risk difference, 1.57 [95% CI, -0.52 to 3.66]), suggesting potential bias from healthcare utilization. Although the study controlled for outpatient services, the authors noted, women using vaginal estrogen might “exhibit greater health-seeking behavior” than those not using the therapy.

IN PRACTICE:

"As the rates of endometrial cancer have been increasing in younger women, this study addresses a timely topic that has major implications for endometrial cancer survivors’ quality of life,” the authors wrote. They stressed that menopausal symptoms are unique to each woman, and patients and physicians “need to engage in shared decision-making” when considering the use of vaginal estrogen therapy for genitourinary symptoms.

SOURCE:

The study, led by Christine D. Hsu, PharmD, PhD, of the University of Texas Medical Branch at Galveston, was published on March 3 in Menopause.

LIMITATIONS: 

The primary outcome was assessed using a proxy method because there is no ICD code for endometrial cancer recurrence. Vaginal estrogen therapy claims reflect prescriptions but do not confirm whether women used the medication. The average duration of vaginal estrogen use precludes an evaluation of outcomes associated with long-term use.

DISCLOSURES:

The study received funding from the US National Institutes of Health. The authors reported no relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.