Survival Outcome and Impact of Chemotherapy in T1 Node-Negative Triple-Negative Breast Cancer: A SEER Database Analysis

Benefit of adjuvant chemotherapy for T1cN0M0 and selected T1bN0M0 triple-negative breast cancer: a nationwide cancer registry-based study

BACKGROUND

The efficacy of adjuvant chemotherapy for T1N0M0 triple-negative breast cancer (TNBC) has not been clearly elucidated. Thus, we aimed to evaluate the efficacy of adjuvant chemotherapy for patients with T1a-cN0M0 TNBC.

PATIENTS AND METHODS

Patients newly diagnosed with TNBC between 2011 and 2015 were identified and followed up until the end of 2020 using the Taiwan Cancer Registry. Univariate and multivariate Cox proportional hazards regression analyses were performed to compare the recurrence-free survival (RFS) and OS between patients who received and those who did not receive adjuvant chemotherapy.

RESULTS

Of the 62 483 patients registered during 2011-2015, 1074 patients with T1N0M0 TNBC (T1a, n = 103; T1b, n = 167; and T1c, n = 804) who underwent definitive breast surgery were included. Overall, 850 (79%) patients received adjuvant chemotherapy; these comprised 24.3%, 67.7%, and 88.6% of the patients with T1a, T1b, and T1c disease, respectively. Over a median follow-up of 7.18 years, a significant RFS and OS benefit from adjuvant chemotherapy was observed in the T1c subgroup but not in the T1a and T1b subgroups. However, subgroup analysis of T1b disease indicated that adjuvant chemotherapy yielded an OS benefit to patients with histological grade III disease (adjusted hazard ratio = 0.08, 95% CI, 0.01-0.77; P = .03).

CONCLUSIONS

Adjuvant chemotherapy improved the RFS and OS in patients with T1cN0M0 TNBC and improved the OS in patients with histological grade III T1bN0M0 disease. Our study advocates for the utilization of adjuvant chemotherapy in patients diagnosed with T1cN0M0 and histological grade III T1bN0M0 TNBC.

Does T1c-2N0-1M0 triple negative breast cancer derive a benefit from neoadjuvant chemotherapy?

OBJECTIVES

Although neoadjuvant chemotherapy (NCT) is a standard approach for operable triple negative breast cancer (TNBC), the potential risks brought by it should also be noticed. Is the expanding indication of NCT to T1cN0M0 population appropriate? We conducted an investigation to compare the long-term survival of small tumor TNBC between NCT and adjuvant chemotherapy (ACT).

METHODS

For this propensity-matched analysis, we used data from Surveillance, Epidemiology, and End Results (SEER) database. We enrolled 1183 cases with NCT and 2550 cases with ACT who are AJCC clinical T1c-T2 N0-N1, diagnosed with invasive triple-negative breast cancer, from 2016 to 2017. The propensity score matching was utilized to minimize baseline characteristics bias. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated by the Cox proportional hazard regression model.

RESULTS

Compared with patients receiving ACT, patients with NCT in this study presented a higher proportion of younger age, T2 stage, N1 stage, and underwent more mastectomy. Multivariate analysis in matched patients showed that NCT had no significant survival benefit compared with ACT in T1c-2N0-1M0 TNBC patients. Stratified analyses by T stage and N stage demonstrated NCT mainly presented a survival advantage in patients with N1 stage. Further investigation found that NCT didn't improve BCSS (HR, 0.472; 95% CI 0.135-1.647; P = 0.239) and OS (HR, 0.392; 95% CI 0.147-1.047; P = 0.062) for patients with T1cN0M0 TNBC; however, it was associated with improved OS (HR, 1.951; 95% CI 1.003-3.797; P = 0.049) only for patients with T2N1M0 TNBC.

CONCLUSIONS

In this study, we did not find any profit brought by NCT in the stage I and stage IIa cohorts, but even more unfavorable outcomes appeared in the T1cN0M0 cohort. Therefore, whether the candidates of NCT should be extended to T1cN0M0 still need to be cautious.

Nanoparticle drug delivery systems responsive to tumor microenvironment: Promising alternatives in the treatment of triple-negative breast cancer

The conventional therapeutic treatment of triple-negative breast cancer (TNBC) is negatively influenced by the development of tumor cell drug resistant, and systemic toxicity of therapeutic agents due to off-target activity. In accordance with research findings, nanoparticles (NPs) responsive to the tumor microenvironment (TME) have been discovered for providing opportunities to selectively target tumor cells via active targeting or Enhanced Permeability and Retention (EPR) effect. The combination of the TME control and therapeutic NPs offers promising solutions for improving the prognosis of the TNBC because the TME actively participates in tumor growth, metastasis, and drug resistance. The NP-based systems leverage stimulus-responsive mechanisms, such as low pH value, hypoxic, excessive secretion enzyme, concentration of glutathione (GSH)/reactive oxygen species (ROS), and high concentration of Adenosine triphosphate (ATP) to combat TNBC progression. Concurrently, NP-based stimulus-responsive introduces a novel approach for drug dosage design, administration, and modification of the pharmacokinetics of conventional chemotherapy and immunotherapy drugs. This review provides a comprehensive examination of the strengths, limitations, applications, perspectives, and future expectations of both novel and traditional stimulus-responsive NP-based drug delivery systems for improving outcomes in the medical practice of TNBC. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Retrospective Study of Treatment Patterns and Natural History of Patients with T1a/b N0 Triple-Negative Breast Cancers: A Single-Institution Experience

INTRODUCTION

T1a/b, node-negative (node-), triple-negative breast cancers (TNBCs) are underrepresented in randomized drug-approving clinical trials. Given their low incidence, the clinicopathological features, natural history, and treatment patterns of these tumors remain insufficiently understood.

METHODS

We conducted a single-institution retrospective cohort study of patients with T1a/b, N0, M0 TNBCs. Deidentified patient- and tumor-related data were collected and summarized. Kruskal-Wallis, χ2, or Fisher exact tests were used to evaluate associations of interest. Kaplan-Meier methods, log-rank tests, and Cox's proportional hazards models were applied for survival analyses.

RESULTS

Of 108 cases of node- TNBCs measuring ≤2 cm, 34 node- T1a/b tumors were included in our analysis. All cases had an intermediate to high histological grade, and most had a Ki-67 score of ≥20%. All patients received adjuvant chemotherapy, and many underwent mastectomy (47%). Docetaxel combined with cyclophosphamide was the most common adjuvant chemotherapy regimen (75%). We did not observe significant associations between improved outcomes and treatment with anthracycline-containing regimens. Among patients with node- pT1a/b tumors, the estimated 3-year recurrence-free survival (RFS) and distant RFS rates were both 96.3% (95% CI: 76.5-99.5), and the overall survival rate was estimated to be 100% (95% CI: 100-100). There were no cases of local recurrences observed.

CONCLUSIONS

In our cohort, all patients with T1a/b node- TNBCs were treated with adjuvant chemotherapy and had favorable outcomes even when treated with anthracycline-sparing regimens.

Survival benefit of adjuvant chemotherapy in elderly patients with stage I triple-negative breast cancer: a cohort study based on the SEER database

Background

This study analyzed the trend and prognostic role of postoperative adjuvant chemotherapy (POCT) in patients with stage I triple-negative breast cancer (TNBC) aged more than 65 years. In addition, the relationship between POCT and survival rate was also determined.

Methods

The Surveillance, Epidemiology, and End Results (SEER) database was collected to determine 3,307 TNBC elderly women aged ≥65 years between 2010 and 2016, and they were divided into POCT and non-POCT groups. Propensity score matching (PSM) method was used to offset the differences in baseline characteristics between the groups. Kaplan-Meier plots were tested to contrast overall survival (OS) and breast cancer-specific survival (BCSS) between the two groups. The Cox proportional hazard model was constructed to assess the prognostic factors affecting OS and BCSS.

Results

Younger age, higher histological grade, married, postoperative radiotherapy, lumpectomy, larger tumor, and closer year of diagnosis were related to an enhanced likelihood of adjuvant chemotherapy. After PSM, POCT was related to increased 5-year OS [hazard ratio (HR): 0.571, 95% confidence interval (CI): 0.432-0.753, respectively], without significant difference in BCSS improvement. Exploratory subgroup analysis demonstrated that POCT contributed to OS improvement in both IA and IB patients, but did not improve BCSS in IA and IB patients.

Conclusions

In elderly patients ≥65 years, POCT improved 5-year OS in stage I TNBC patients, while further exploration with larger prospective trials are needed.