Black women with breast cancer less likely to respond to neoadjuvant chemotherapy
Black women appeared less likely than those from other racial backgrounds to benefit from neoadjuvant chemotherapy, according to results of a database study.
In addition, black women appeared less likely to achieve pathologic complete response for triple-negative or HER-2–positive breast cancer.
Brigid K. Killelea, MD, MPH, FACS
“We serve a diverse population, and we see a lot of younger women with triple negative breast cancer and HER-2–positive breast cancer,” Brigid K. Killelea, MD, MPH, FACS, associate professor of surgical oncology at Yale School of Medicine, told HemOnc Today. “Knowing that there are disparities of survival for black women, we wanted to see if we could access the available data for pathologic complete response, which is a newer addition to the National Cancer Data Base and has not been widely studied.”
Killelea and colleagues used the National Cancer Data Base to identify 278,815 women diagnosed with stage I to stage III breast cancer in 2010 and 2011.
Forty-six percent (n = 127,417) received chemotherapy, of whom about one-fifth received neoadjuvant chemotherapy.
Compared with non-Hispanic white women, black, Hispanic and Asian women were more likely to receive any type of chemotherapy and neoadjuvant chemotherapy (P < .001).
The researchers attributed the greater receipt of chemotherapy in minority women to several factors, including more advanced disease stage, as well as a greater proportion of triple-negative and HER-2–positive disease.
Killelea and colleagues had data on outcomes from 17,970 patients. Thirty-three percent (n = 5,944) achieved a pathologic complete response.
Researchers reported no difference in response rate for ER- or PR-positive tumors based on race. However, black women had a lower rate of pathologic complete response than white women for triple-negative breast cancer (37% vs. 43%; P < .001) and HER-2–positive breast cancer (43% vs. 54%; P = .001).
The difference persisted after adjustment for age, clinical T stage, clinical N stage, histology, grade, comorbidity index, facility type, geographic location, insurance status, and median income and education of the patient’s zip code (OR = 0.84; 95% CI, 0.77-0.93).
Hispanic and Asian women did not have a significantly lower rate of pathologic complete response compared with white women.
The researchers could not determine whether these differences were caused by biologic differences in chemosensitivity, or to treatment or sociological differences for which they could not adjust.
“We have identified a disparity in terms of pathologic complete response,” Killelea said. “Moving forward, it is really important to encourage black, Hispanic and Asian women to participate in clinical trials so that they can be adequately represented when we investigate new drugs.” – by Cameron Kelsall
For more information:
Brigid K. Killelea, MD, MPH, FACS, can be reached at email@example.com.
Disclosure: Killelea reports no relevant financial disclosures. Please see the full study for a list of all other researchers’ relevant financial disclosures.