Racial and Ethnic Disparity in Preoperative Chemosensitivity and Survival in Patients With Early-Stage Breast Cancer

Abstract

ImportanceIt remains unclear what survival benefit is associated with preoperative chemosensitivity after receiving neoadjuvant chemotherapy (NACT) among patients with resectable breast cancer from diverse racial and ethnic backgrounds.ObjectiveTo investigate racial and ethnic disparities in chemosensitivity and association with survival in patients with early-stage breast cancer.Design, Setting, and ParticipantsThis retrospective cohort study queried data from the National Cancer Database (NCDB) between calendar years 2010 and 2018. Participants included patients with breast cancer with clinical stage I to III disease treated with NACT. Preoperative chemosensitivity was defined as very sensitive (ypT0N0), sensitive (pathologic TNM stage less than clinical stage, excluding ypT0N0), and refractory (pathologic stage greater than or equal to clinical stage). Data were analyzed in November 2022.ExposureReceipt of NACT and clinicopathologic and treatment factors contributing to racial and ethnic disparities in survival.Main Outcomes and MeasuresOverall survival of patients from diverse racial and ethnic backgrounds who received NACT.ResultsThis study included 103 605 patients (median age, 53 [IQR, 44-62] years, 99.5% [n = 103 060] women, and 68.7% [n = 71 203] White race). Among them, breast cancer was refractory in 43.2% (n = 44 796), sensitive in 34.4% (n = 35 638), and very sensitive in 22.4% (n = 23 171) of patients. In the hormone receptor–positive ERBB2 negative (formerly HER2 negative) group, patients had more refractory disease regardless of race or ethnicity (all races and ethnicities refractory: 54%-59%; P < .001). Among ERBB2 positive disease, Black patients had a lower percentage of very sensitive disease (32% vs 37%-40%; P < .001) and among triple-negative breast cancer, more refractory disease was seen among Black patients compared with other races and ethnicities (38% vs 30%-35%; P < .001). In refractory (hazard ratio [HR], 1.53; 95% CI, 1.47-1.60; P < .001) and sensitive (HR, 1.25; 95% CI, 1.17-1.33; P < .001) disease, Black patients had a higher mortality risk compared with White patients in the overall cohort. Asian patients had a lower mortality risk compared with White patients in refractory (HR, 0.71; 95% CI, 0.63-0.80; P < .001), sensitive (HR, 0.58; 95% CI, 0.49-0.69; P < .001), and very sensitive (HR, 0.60; 95% CI, 0.43-0.82; P < .001) disease groups in the overall cohort.Conclusions and RelevanceIn this cohort study, Black patients had a higher mortality risk compared with White patients among those with residual disease after NACT. This highlights the need for personalized treatment strategies for Black patients to help them attain pathologic complete response.

Racial/Ethnic Disparities in Pathologic Complete Response and Overall Survival in Patients With Triple-Negative Breast Cancer Treated With Neoadjuvant Chemotherapy

“…Similar findings were recently reported by Roy et al 29 who assessed racial differences in chemosensitivity (very sensitive = pCR, sensitive = partial response, refractory = no response) among all breast cancer subtypes; they demonstrated that among patients with TNBC, Black women had the lowest rates of very sensitive (25.7%) and the highest rates of refractory disease (38% v 30%-35%; P < .001). However, when Black women achieved pCR, OS did not differ from White (hazard ratio, 0.99 [95% CI, 0.82 to 1.18], P = .23).…”

Predictors of Complete Pathological Response with Chemoimmunotherapy in Triple-Negative Breast Cancer: A Meta-Analysis

“…Another study showed a higher number of TILs in Asians and Native Hawaiian/Pacific Islanders [36]. This difference in the immune microenvironment can play a role in the responses of different races to immunotherapy [23]. However, most of the trials in our meta-analysis did not have subset analysis based on race, so we could not assess the association of race and pCR/survival in our meta-analysis [34].…”

“…The presence of residual disease after neoadjuvant treatment is associated with higher relapse rates in TNBC patients [21]. Although we utilize pCR as an endpoint in clinical trials utilizing neoadjuvant systemic treatments, a longer follow-up time through which to assess EFS and OS is necessary, as pCR might not necessarily translate to better clinical response in some patients, especially in certain racial groups and in certain breast cancer subtypes [22,23].…”

“…Several real-world studies have shown that race can be a predictor for pCR in several malignancies [23,33,34]. Zhao et al have shown that Black patients have lower odds of achieving pCR in hormone receptor-negative HER2-positive breast cancer [33].…”