Impact of race, ethnicity, and BMI on achievement of pathologic complete response following neoadjuvant chemotherapy for breast cancer: a pooled analysis of four prospective Alliance clinical trials (A151426)

Abstract

Purpose Previous studies demonstrated poor response to neoadjuvant systemic therapy (NST) for breast cancer among black women and women who are overweight or obese but this may be due to chemotherapy under dosing. We assessed associations of race, ethnicity and body mass index (BMI) with pathologic complete response (pCR) in clinical trial populations. Methods 1797 women enrolled in four NST trials (CALGB 40601, 40603; ACOSOG Z1041, Z1071) were included. Tumor subtypes were defined by estrogen receptor (ER) and HER2 status. Logistic regression generated odds ratios (OR) and 95% confidence intervals (CI) for the associations of race, ethnicity, and BMI with pCR adjusting for subtype, study arm, lymph node status, tumor size, and tumor grade. Results 253 (14.1%) were black, 199 (11.1%) Hispanic, 520 (28.9%) overweight, and 743 (41.4%) obese. Compared to whites, Blacks and Hispanics were more likely to be obese and Blacks were more likely to have triple-negative cancer. pCR rates differed significantly by tumor subtype. In multivariate analyses, neither race (black vs. white: OR: 1.18, 95% CI: 0.85–1.62) nor ethnicity (Hispanic vs. non-Hispanic: OR: 1.30, 95% CI: 0.67–2.53) were significant predictors of pCR overall or by subtype. Overweight and obese women had lower pCR rates in ER+/HER2+, but higher pCR rates in ER−/HER2+ cancers. Conclusions There was no difference in breast pCR according to race or ethnicity. Overall, there was no major difference in pCR rates by BMI. These findings suggest that pCR with optimally dosed NST is a function of tumor, rather than patient, biology.

Disparities in breast cancer: a multi‐institutional comparative analysis focusing on American Hispanics

“…Ethnic disparities related to breast cancer in Hispanics might be related to several factors noted previously in the literature including inferior participation of Hispanic women in cancer screening programs [17], prevalence of obesity and comorbidities, inadequate insurance coverage as well as less access, adherence, and possibly response to treatment [18][19][20][21]. Furthermore, prior studies have demonstrated that individuals without health insurance are less likely to have a usual source of health care and less likely to receive preventive services including cancer screening and are more likely to be diagnosed with late stages of cancer [22,23].…”

Predicting Successful Conservative Surgery after Neoadjuvant Chemotherapy in Hormone Receptor-Positive, HER2-Negative Breast Cancer

“…HR-positive, HER2-negative subtype. Another possible explanation is that BMI can affect pCR[18]. However, our analyses did not reveal any relationship between BMI and pathological (complete or partial) response in the patient cohort (data not shown).From a surgeon's perspective, it is important to identify the clinical factors that may impact the outcomes of surgical procedures, not the response to NAC.…”

Weight Gain during Neoadjuvant Chemotherapy is Associated with Worse Outcome among the Patients with Operable Breast Cancer

“…The data available on the influence of weight on NAC response has been inconsistent. Some studies suggest that OB patients are less likely to have pathologic complete response (pCR) to NAC and are more likely to experience worse disease-free survival (DFS) and overall survival (OS) [17181920], while others showed contradictory results [212223]. There have been few studies focusing on the influence of weight change during NAC on pCR and long-term survival.…”