Among patients with early-stage breast cancer treated with adjuvant endocrine therapy (AET), symptoms related to sexual health were associated with decreased adherence to treatment in Black women, according to results presented at the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved, held September 21-24, 2024.

Patients with hormone receptor-positive breast cancer are commonly given endocrine therapy—treatments that block estrogen signaling in the breast—after receiving surgery, radiation, or chemotherapy. The recommended regimen for AET can last five to 10 years to decrease the chance of recurrence.

However, many patients experience an array of side effects, including anxiety and depression, hot flashes, and joint pain. These symptoms can lead to nonadherence to AET, marked by premature treatment discontinuation or frequent dose skipping.

Prior studies have shown that Black women are more likely than white women to experience some of these side effects and are also more likely to experience treatment nonadherence, but one subset of AET side effects has remained understudied, explained Janeane N. Anderson, PhD, MPH, an assistant professor in the Department of Community and Population Health within the College of Nursing at the University of Tennessee Health Science Center.

“Up to this point, we’ve mostly talked about AET symptoms as a collective,” Anderson said. “But in research interviews and informal conversations with more than 100 women over the last seven years, I’ve heard over and over that sexual health is one of the greatest unmet needs.”

AET can cause a variety of sexual side effects—including vaginal dryness, reduced libido, and painful intercourse—but Anderson argued that such concerns are not being addressed, especially among minority women. She and her colleagues hypothesized that side effects related to sexual health may contribute to the racial disparities observed in treatment adherence rates.

Anderson and colleagues performed a post-hoc analysis of the THRIVE clinical trial, which assessed adherence to AET among patients treated at the West Cancer Center & Research Institute. Treatment adherence was monitored with an electronic pillbox and reported as the proportion of days patients took their medication over a one-year period. Patients were asked to complete surveys about their symptoms at regular intervals.

The analysis was performed on 102 Black and 173 white patients who completed surveys at enrollment, six months, and 12 months. Surveys assessed both physical (i.e., vaginal itchiness, dryness, bleeding,

and pain) and mental or emotional (i.e., change in interest in sex and sexual satisfaction) sexual health. Physical and mental quality of life were measured using the 12-item Short Form Health Survey, in which higher scores indicated a better quality of life.

Vaginal itchiness, vaginal discharge, painful intercourse, and loss of interest in sex were associated with lower mental quality of life in both Black and white patients at all three time points. Loss of interest in sex was associated with lower physical quality of life in Black patients only.

Vaginal dryness (at six months), as well as decreased libido and sexual satisfaction (at 12 months) were associated with lower AET adherence for Black patients but not for white patients.

“The evidence shows that women are really being bothered by these symptoms,” Anderson said. “The takeaway from this is that Black and white women experience some of these symptoms differently.”

Anderson stressed that there are both hormonal and nonhormonal treatments that may mitigate some of these symptoms, including vaginal moisturizers, topical estrogen, and counseling. She emphasized that open communication about sexual health between patients and oncologists—at frequent intervals during treatment—is key to helping patients manage their symptoms so they can stay on AET.

“If we can start addressing some of these symptoms, we may start seeing parity in Black and white women’s AET adherence,” Anderson said. “Women are making the decision to either maintain adherence or reclaim their sexuality, and hopefully we can make it so that they don’t have to make that choice anymore.”

Limitations of this study include data sourced from a single cancer center, potentially limiting the applicability of the findings to other treatment settings or geographic regions. Further, limited recruitment of women from other minority groups—including Latinas, Asian Americans, and sexual minorities—resulted in little data on sexual health symptoms in those groups.

Funding for this study was provided by the National Cancer Institute of the National Institutes of Health. Anderson declares no conflicts of interest.

This news release was published by the American Association for Cancer Research on September 21, 2024.