番茄社区

SAN ANTONIO -- Women of color, and Black women in particular, appeared more likely to develop lymphedema after undergoing axillary lymph node dissection (ALND), a researcher reported here.

In a prospective, breast cancer-related lymphedema (BCRL) study with a median 24 months follow-up, multivariable analysis demonstrated that Black women were 3.5 times more likely to experience arm or leg swelling after ALND versus white women (odds ratio [OR] 3.53, 95% CI 1.93-6.47), according to Andrea Barrio, MD, of Memorial Sloan Kettering Cancer Center in New York City.

And Hispanic women had a threefold increased risk of lymphedema post-ALND versus white women (OR 3.11, 95% CI 1.16-7.73), she reported at the San Antonio Breast Cancer Symposium.

However, Barrio and colleagues noted that the number of Hispanic women in the study was small so further research is needed to confirm the findings.

While there is some evidence that Black women are more likely than white women to experience BCRL, Barrio explained that most studies of BCRL do not report the racial or ethnic breakdown of the patient populations. Furthermore, most research on lymphedema has relied on patients' self-reported symptoms or lymphedema diagnosis codes.

Barrio and colleagues performed bilateral arm measurements with a perometer at baseline, after the initial operation, and every 6 months after the surgery for 2 years. If the relative increase in arm volume was at least 10% from baseline, it was considered a lymphedema diagnosis.

They enrolled 304 breast cancer patients who underwent ALND from November 2016 to March 2020; 276 patients had at least one longitudinal measurement after baseline in the analysis. The majority of participants were white (60%), while 20% were Black, 11% were Asian, 6% were Hispanic, and 3% did not report race or ethnicity.

The 12- and 24-month lymphedema rates were 8.8% and 24.7%, respectively, among all women in the study. At the 24-month timepoint, 39.4% of Black women, 27.7% of Hispanic women, 23.4% of Asian women, and 20.5% of white women had been diagnosed with lymphedema.

Other factors independently linked with post-ALND lymphedema were:

• Receipt of neoadjuvant chemotherapy vs upfront surgery: OR 2.07 (95% CI 1.14-3.94)
• Older age (per 1-year increase): OR 1.04 (95% CI 1.01-1.06)
• Time from surgery (per every 6-month increase): OR 1.7 (95% CI 1.37-2.13)

There was no difference in lymphedema severity across racial and ethnic groups, with similar relative volume changes observed, according to the authors.

Alphonse Taghian, MD, PhD, of Mass General Cancer Center/Harvard Medical School in Boston, explained to 番茄社区, that previously, "we noted that Black women seemed to have more lymphedema, but we thought that might have been due to other factors, like more advanced disease requiring more extensive treatment -- like ALND, radiation -- or [because of] higher BMI. These are the well-known risk factors to develop BCRL for any patients independent of race."

Taghian, who was not involved in the study, called it "very well conducted [as it] corrected for those types of variables." The study indicated that "something else is making these women more susceptible to lymphedema. We really have no idea what that is or why." He stated that longer follow-up and data from a larger number of patients at multiple institutions may be needed to find those answers.

Barrio pointed out that inflammation and fibrosis are key in the pathogenesis of lymphedema, and Black women may have an increased propensity toward inflammation and/or increased fibrosis, especially in response to radiation therapy." She added that a better understanding of lymphedema would help for designing risk reduction strategies.

Study limitations included the short follow-up time. Barrio said her group will continue to follow the women to obtain more long-term data, and that they plan to assess the biologic mechanisms behind racial disparities in lymphedema development, including the potential role of, a known marker of systemic inflammation.

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