Black Race Found to Be Strongest Predictor of Lymphedema After Axillary Lymph Node Dissection

In In The News by Barbara Jacoby

By: Kate O’Rourke

From: clinicaloncolog

Black race and use of neoadjuvant chemotherapy (NAC) are associated with higher rates of breast cancer–related lymphedema, according to the results of a prospective screening study.

The study, presented at the 2021 San Antonio Breast Cancer Symposium (GS4-01), involved analysis of 276 patients with breast cancer undergoing axillary lymph node dissection (ALND) and radiation. Enrolled patients underwent measurements of arm volume and body mass at baseline, postoperatively and at six-month intervals. Lymphedema was defined as a relative increase in arm volume of at least 10% from baseline. At trial enrollment, the median age was 48 years and median body mass index was 26.4 kg/m2. Sixty percent of the trial participants were white, 20% Black, 11% Asian and 6% Hispanic.

At a median follow-up of 22.6 months, 56 of the trial participants had developed lymphedema. The two-year lymphedema rate was 39.4% in Black women, 27.7% in Hispanic women, 23.4% in Asian women and 20.5% in white women.

On multivariable analysis, the researchers found that Black race was the strongest predictor of lymphedema development, with a 3.5-fold increased incidence of lymphedema in Black women compared with white women (P<0.001).

“The etiology for the higher incidence of lymphedema in Black women is largely unknown but may be due to race-based differences in inflammatory reactions, tissue fibrosis and lymphatic function,” according to lead investigator Andrea Barrio, MD, an associate attending physician in the breast service, Department of Surgery, at Memorial Sloan Kettering Cancer Center, in New York City.

Hispanic women in the study had a threefold increased risk for lymphedema compared with white women; however, the Hispanic study population was small, and the researchers said further research is necessary to confirm these findings.

The researchers also identified a higher incidence of lymphedema in patients who had NAC than in those who underwent up-front surgery, with lymphedema rates of 30.9% and 11.1%, respectively (P=0.017).

“We postulate that neoadjuvant chemotherapy may cause fibrosis of tumor-filled lymphatics as well as lymphatic endothelial damage prior to surgery, resulting in the higher lymphedema incidence observed in our study,” Dr. Barrio said at a press conference during the meeting. “In patient subsets unlikely to achieve a nodal pathologic complete response with NAC, alternatives to NAC to avoid ALND are needed.”

Other factors, including older age and increasing time from surgery, were associated with a modest increased risk for lymphedema.

“We already know that African American women have a higher rate of triple-negative breast cancer, which is one of the most aggressive breast cancers to treat. Now we are seeing in a very well conducted trial that African American women have a higher risk of lymphedema,” commented Virginia Kaklamani, MD, who was not involved with the study, during the press conference. “I think it’s important for us to recognize this, recognize the symptoms early and treat our patients preemptively so that we can potentially prevent lymphedema in these patients,” Dr. Kaklamani, a professor of medicine in the Division of Hematology/Oncology at UT Health San Antonio MD Anderson Cancer Center.

Rachel Greenup, MD, MPH, the chief of breast surgery at the Breast Center at Yale School of Medicine’s Smilow Cancer Hospital, in New Haven, Conn., said the findings highlight the importance of universal and unbiased screening for breast cancer treatment side effects to identify individuals who will benefit from referral to physical therapy, nutrition and exercise counseling, as well as ongoing follow-up for lymphedema surveillance. “Findings from this study should prompt general and subspecialty surgeons treating breast cancer to have a heightened awareness around the increased risk of breast cancer–related lymphedema in Black women, and may warrant purposeful referral for lymphedema care among women of color.”