Clinical Outcomes of Single Versus Double Hormone Receptor–Positive Breast Cancer Patients Treated With Neoadjuvant Chemotherapy

Clinical Outcomes and Intrinsic Subtypes of Breast Cancer Patients with Single Hormone Receptor-positive Receiving Neoadjuvant Chemotherapy

BACKGROUND

Extensive studies have highlighted the significance of estrogen receptor (ER) and progesterone receptor (PR) in breast cancer (BRCA). However, our understanding of patients with single hormone receptor (HR)-positive (sHR+) BRCA remains limited. This lack of understanding poses challenges in predicting prognosis and selecting appropriate treatments.

PATIENTS AND METHODS

We collected data from a total of 825 human epidermal growth factor receptor 2 negative (HER2-) BRCA patients who underwent neoadjuvant chemotherapy (NAC) in two distinct cohorts. Four subgroups were created within each cohort based on their HR expression: ER+/PR+, ER+/PR-, ER-/PR+, and ER-/PR-. We conducted comparative analyses to assess clinicopathological characteristics, chemotherapy responsiveness, clinical outcomes, and intrinsic subtyping among these subgroups.

RESULTS

ER+/PR- constituted 11.1% and 14.9% of samples in two cohorts, respectively, whereas ER-/PR+ comprised 8.3% and 3.7%. Higher histologic grades were more common in the ER-/PR+ group as compared to the ER+/PR+ subgroup (P = .0075 in cohort 1; P = .026 in cohort 2). Additionally, after multivariable analysis, ER-/PR+ were more likely to achieve pathological complete response (pCR) (cohort 1: OR =6.67; 95%CI, 2.63-16.94; P < .001; cohort 2: OR =3.70; 95%CI, 1.08-11.84; P = .030;). Between ER+/PR- and ER+/PR+, the distant recurrence-free survival (DRFS) was comparable. The survival outcomes in the ER-/PR+ subgroup present a partial inconsistency between the 2 cohorts. Furthermore, the ER-/PR+ subgroup exhibited a higher incidence of the basal-like subtype, while the ER+/PR- subgroup had a higher proportion of luminal-like subtypes.

CONCLUSION

This study highlighted the distinct clinical and genetic characteristics of sHR+ BRCA, emphasizing the potential need for optimized treatment strategies.

Real-world data on breast pathologic complete response and disease-free survival after neoadjuvant chemotherapy for hormone receptor-positive, human epidermal growth factor receptor-2-negative breast cancer: a multicenter, retrospective study in China

BACKGROUND

The data in the real-world setting on breast pathologic complete response (pCR) after neoadjuvant chemotherapy (NAC) for hormone receptor-positive, human epidermal growth factor receptor-2-negative (HR+, HER2-) breast cancer (BC) is limited. The present study aims to screen for some predictors and investigate the prognostic significance of breast pCR after NAC in HR+, HER2- BC in China.

METHODS

This was a multicenter, retrospective study. In this study, three hundred eighty-four HR+, HER2- BC patients who received NAC were enrolled between 2010 and 2016 from Shanghai Jiaotong University Breast Cancer Database (SJTU-BCDB). These patients were dichotomized according to the presence of breast pCR after NAC. Logistic analysis was used to screen for predictors associated with breast pCR. Kaplan-Meier (K-M) curve and a propensity score matching (PSM) analysis were performed to compare the disease-free survival (DFS) between the two groups. Cox regression was used to analyze the prognostic significance of breast pCR on DFS in HR+, HER2- BC. A nomogram model was established to predict the probability of DFS at 1, 3, and 5 years after NAC.

RESULTS

Fifty-seven patients (14.8%) achieved breast pCR. Univariate analysis showed that tumor size, estrogen receptor (ER), progesterone receptor (PR), and Ki67 were associated with breast pCR. Further, multivariate analysis showed that tumor size, PR, and Ki67 remained statistically significant. K-M curves showed a statistical difference between the breast pCR and non-pCR groups before PSM (p = 0.047), and a more significant difference was shown after PSM (p = 0.033). Cox regression after PSM suggested that breast pCR, adjuvant ET, clinical T stage, and Ki67 status were the significant predictive factors for DFS in HR+, HER2- BC patients. The adjusted hazards ratio (aHR) for breast pCR was 0.228 (95% CI, 0.070~0.739; p = 0.014), for adjuvant endocrine therapy was 0.217 (95% CI, 0.059~0.801; p = 0.022), for Ki67 was 1.027 (95% CI, 1.003~1.052; p = 0.027), for cT stages 2 and 3 compared with 1, the values were 1.331 (95% CI, 0.170~10.389), and 4.699 (95% CI, 0.537~41.142), respectively (p = 0.043). A nomogram was built based on these significant predictors, providing an integrated probability of DFS at 1, 3, and 5 years. The values of area under the receiver operating characteristic (ROC) curve (AUC) were 0.967, 0.991, and 0.787, at 1 year, 3 years, and 5 years, respectively, demonstrating the ability of the nomogram to predict the DFS.

CONCLUSIONS

This real-world study demonstrates that tumor size, PR, and Ki67 were independent predictive factors for breast pCR in HR+, HER2- BC. Breast pCR after NAC was an independent predictor for DFS in HR+, HER2- patients, regardless of a change in nodes. Furthermore, the nomogram built in our study could predict the probability of individualized DFS in HR+, HER2- BC patients.

Neoadjuvant chemotherapy in hormone receptor-positive/HER2-negative early breast cancer: When, why and what?

Indication for neoadjuvant chemotherapy (NACT) in HR+/HER2-negative tumors is controversial. Pathological complete response (pCR) rates range from 0 to 18 % while breast-conserving surgery (BCS) is achievable in up to 60 % of tumors. No pathological feature definitely predicts pCR; lobular and molecular luminal A tumors are less likely to achieve pCR although experiencing better outcomes. Luminal B subtype, high proliferation, lack of progesterone receptor, high tumor-infiltrating lymphocytes are positively associated with increased pCR rates but worse outcomes and the prognostic role of pCR is inconsistent across studies. Molecular intrinsic subtyping and genomic signatures appear as more accurate predictors of benefit from NACT, but larger studies are needed. Anthracycline and taxane-based chemotherapy remains the standard NACT; however, CDK 4/6 inhibitors and immune checkpoint inhibitors are under evaluation. In conclusion, NACT may be proposed for luminal tumors requiring downsizing for BCS after multidisciplinary evaluation, provided that other contraindications to BCS are excluded.

Clinical Characteristics and Outcomes of Single Versus Double Hormone Receptor-Positive Breast Cancer in 2 Large Databases

PURPOSE

To identify biologic and outcome differences between double hormone receptor (HR)-positive (dHR⁺, estrogen receptor (ER)⁺/progesterone receptor [PgR⁺]) and single HR-positive (sHR⁺, either ER⁺/PgR^- or ER^-/PgR⁺) breast cancer; and to explore whether hormone therapy (HT) response in HER2-negative breast cancer correlates with HR status.

PATIENTS AND METHODS

This retrospective study was conducted by using 2 large breast cancer databases: the Surveillance, Epidemiology, and End Results (SEER) database and the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) clinical data set. Cox regression analysis was used to estimate overall survival (OS) and breast cancer-specific survival (BCSS) among sHR⁺ and dHR⁺ patients.

RESULTS

In the SEER database, dHR⁺ patients had significantly longer OS and BCSS than ER⁺/PgR^- patients in short-term follow-up (OS: hazard ratio = 0.620; 95% confidence interval [CI], 0.590, 0.652; P < .001; BCSS: hazard ratio = 0.493; 95% CI, 0.462, 0.526; P < .001). Meanwhile, ER^-/PgR⁺ patients had younger age, larger tumor size, and higher disease grade than dHR⁺ and ER⁺/PgR^- patients. In patients who received HT, dHR⁺ patients had a more favorable OS than ER⁺/PgR^- patients (hazard ratio = 0.789; 95% CI, 0.635, 0.982; P = .034), and ER^-/PgR⁺ patients had a worse OS than ER⁺/PgR^- patients at 10 years' follow-up (hazard ratio = 7.991; 95% CI, 1.053, 60.644; P = .044). However, these groups had similar outcomes over longer periods.

CONCLUSION

In HER2-negative breast cancer, sHR⁺ patients are associated with relatively worse characteristics and worse short-term outcomes than dHR⁺ patients. Additionally, the outcome of patients receiving HT may differ according to the HR status. However, further studies are needed to confirm these conclusions.