Efficacy of Neoadjuvant Versus Adjuvant Chemotherapy in Hispanic/Latino (H/L) Women With Local or Locally Advanced Triple-negative Breast Cancer (TNBC)

Abstract

Background/Aim: The aim of the study was to investigate the efficacy of neoadjuvant and chemotherapy (NACT) and adjuvant chemotherapy (ACT) in Hispanic/Latino (H/L) women with TNBC. Patients and Methods: We reviewed the charts of patients with TNBC, stages I-III, treated at TTUHSC from 2006 to 2016. Overall survival (OS) and recurrence-free survival (RFS) were estimated and compared between the treatment groups. Kaplan-Meier curve and Cox proportional hazards regression analyses were conducted to estimate unadjusted and adjusted effects of NACT compared to ACT. Results: A total of 104 patients with TNBC, 30 (29%) received NACT and 74 (71%) ACT. Women undergoing NACT were younger, with a mean age of 50.8 years. Of the 30 patients who received NACT, 12 (40%) had pathologically complete response (pCR). Women who achieved pCR had an excellent RFS (HR=0.5, p=0.001). Women with residual cancer after NACT had worse outcome compared to patients who received ACT (HR=1.7, p=0.005). Conclusion: pCR to NACT is a powerful surrogate for OS in H/L women with TNBC. Breast cancer is the second leading cause of cancer death after lung cancer. In 2019, the American Cancer Association estimated that there were 252,700 new cases of breast cancer in the United States and 41,000 deaths from the disease (1, 2). Breast cancer is a heterogeneous disease, biologically characterized by the expression of one or more steroid hormone receptors such as estrogen receptor (ER) or progesterone receptor (PR) along with the oncogeneepidermal growth factor receptor ErbB2 (Her-2neu). Of those subtypes, triple-negative breast cancer (TNBC) is biologically defined by the absence of expression of ER, PR, and Her-2neu receptors (3). It is a heterogenic subgroup of breast cancer that comprises approximately 15% of all types of breast cancer. TNBC is highly aggressive and has worse disease-specific outcomes than any other subtype of breast cancer (3, 4). One possible explanation is the absence of well-defined molecular targets such as ER, PR, or Her2-neu, which limits options for treating this subtype of breast cancer. Systemic chemotherapy has remained the only available option for these patients for almost two decades. Historically, NACT has been used to downstage unresectable breast cancer to allow for better locoregional control and to increase the chance for breast-conserving surgery. It has been recognized that NACT represents an excellent in vivo approach to directly test tumor sensitivity to chemotherapy. Unfortunately, the large National Surgical Adjuvant Breast and Bowel Project (NSABP) randomized clinical trial B-18 did not show any statistically significant difference in the overall survival (OS) between patients who underwent NACT and those who underwent adjuvant chemotherapy (ACT) (5). There was, however, a trend in favor of NACT in women younger than 50 years of age. The major limitation of the B-18 trial was the lack of subgroup analysis by hormonal status. Furthermore, multiple published retrospective clinical studies comparing the efficacy...

Survival outcomes of neoadjuvant versus adjuvant chemotherapy in triple-negative breast cancer: a meta-analysis of 36480 cases. 

“…Table 1 and table 2 presents , and heterogeneity was detected in these data (I 2 =96% P<0.01). Three studies reported the breast conserving surgery rate, from which we found that the breast conserving rate after NACT was lower than ACT (RR = 0.84;95% CI = 0.57-1.23; P =0.37) [12,14,20] (Figure 3), and heterogeneity was detected in these data (I 2 =82%, P=0.004)…”

“…Signi cant heterogeneity existed among the studies (I 2 =88%, P<0.000001). Unlike TNBC patients who received ACT those with RD who were put on NACT had worse OS (HR = 1.18; 95%CI = 1.09-1.28; P<0.0001), while those who achieved pCR following NACT had signi cant OS bene ts (HR = 0.53; 95%CI = 0.29-0.98; P=0.04) in the studies of Clifton, Fisher, Bagegni and Philipovskiy [12,13,19,20]. Heterogeneity did not exist among the included studies as shown in Figure 4.…”

“…The OS of NACT versus ACT in TNBC in the entire study was evaluated in the Clifton, Fisher, Kennedy, Cheng, Yang, Biswas, Bagegni and Philipovskiy trials with a sample size of 36422 [12][13][14][16][17][18][19][20]. After a median follow-up of 4.12 years, NACT led to worse OS than ACT with an HR of 1.59; 95%CI (1.25-2.02); P=0.0001.…”

“…The trials by Clifton, Sharma and Philipovskiy trials [12,15,20], reported DFS after NACT versus ACT in TNBC. A total of 569 patients were included in the pooled analysis with a median follow-up time of 5.14 years.…”

“…The keywords used in the search strategy were triplenegative breast neoplasms OR triple-negative breast cancer OR triple-negative breast carcinoma AND neoadjuvant OR preoperative AND Adjuvant chemotherapy OR chemotherapy. A total of nine articles with a total of 36480 patients met the eligibility criteria [12][13][14][15][16][17][18][19][20]. The inclusion of studies was not limited to geographical location of study or publication language.…”