Does guideline non-adherence result in worse clinical outcomes for hormone receptor-positive and HER2-negative metastatic breast cancer in premenopausal women?: result of an institution database from South Korea

Comparison of endocrine therapy and chemotherapy as different systemic treatment modes for metastatic luminal HER2-negative breast cancer patients —A retrospective study

Purpose

The purpose of this study was to evaluate endocrine therapy and chemotherapy for first-line, maintenance, and second-line treatment of hormone receptor-positive HER-2-negative metastatic breast cancer (HR+HER-2-MBC) and the relationship between different treatment options and survival.

Patients and methods

The patients included in this study were all diagnosed with metastatic breast cancer (MBC) at Shandong Cancer Hospital from January 2013 to June 2017. Of the 951 patients with MBC, 307 patients with HR+HER-2-MBC were included in the analysis. The progression-free survival (PFS) and overall survival (OS) of the various treatment modes were evaluated using Kaplan–Meier analysis and the log-rank test. Because of the imbalance in data, we used the synthetic minority oversampling technique (SMOTE) algorithm to oversample the data to increase the balanced amount of data.

Results

This retrospective study included 307 patients with HR+HER-2-MBC; 246 patients (80.13%) and 61 patients (19.87%) were treated with first-line chemotherapy and first-line endocrine therapy, respectively. First-line endocrine therapy was better than first-line chemotherapy in terms of PFS and OS. After adjusting for known prognostic factors, patients receiving first-line chemotherapy had poorer PFS and OS outcomes than patients receiving first-line endocrine therapy. In terms of maintenance treatment, the endocrine therapy-endocrine therapy maintenance mode achieved the best prognosis, followed by the chemotherapy-endocrine therapy maintenance mode and chemotherapy-chemotherapy maintenance mode, and the no-maintenance mode has resulted in the worst prognosis. In terms of first-line/second-line treatment, the endocrine therapy/endocrine therapy mode achieved the best prognosis, while the chemotherapy/chemotherapy mode resulted in the worst prognosis. The chemotherapy/endocrine therapy mode achieved a better prognosis than the endocrine therapy/chemotherapy mode. There were no significant differences in the KI-67 index (<15%/15-30%/≥30%) among the patients receiving first-line treatment modes, maintenance treatment modes, and first-line/second-line treatment modes. There was no statistical evidence in this study to support that the KI-67 index affected survival. However, in the first-line/second-line model, after SMOTE, we could see that KI-67 ≥ 30% had a poor prognosis.

Conclusions

Different treatment modes for HR+HER-2-MBC were analyzed. Endocrine therapy achieved better PFS and OS outcomes than chemotherapy. Endocrine therapy should be the first choice for first-line, maintenance, and second-line treatment of HR+HER-2-MBC.

Real world initial palliative treatment patterns and clinical outcomes in premenopausal patients with hormone receptor-positive, HER2-negative metastatic breast cancer: A study of the National Cancer Center, China

BACKGROUND

To observe whether guideline non-adherence in initial palliative treatment choices for premenopausal hormone receptor-positive (HR+), HER2-negative metastatic breast cancer (MBC) patients result in worse clinical outcomes in the Chinese population.

METHODS

The China National Cancer Center database was used to identify 2194 patients diagnosed between 2004 and 2015. A total of 451 premenopausal patients with HR + HER2- MBC were included. Clinicopathological features and survival information were extracted. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method and compared using log-rank test.

RESULTS

The number of patients receiving initial chemotherapy, endocrine therapy and chemo-endocrine therapy were 222 (49.2%), 80 (17.7%), and 149 (33.0%), respectively. Patients receiving initial chemotherapy were more likely to be luminal B subtype, had more de novo stage IV disease and more liver metastasis, compared with patients receiving initial endocrine therapy. Both PFS and OS were significantly longer for chemo-endocrine therapy group (median PFS 18.9 months and OS 75.0 months), than for endocrine therapy group (median PFS 11.7 months and OS 53.5 months), and chemotherapy group (median PFS 7.1 months and OS 43.9 months). In multivariate analysis, none of the three treatment strategies were independently associated with PFS or OS.

CONCLUSION

In real world, a high percentage of premenopausal patients with HR + HER2- disease received chemotherapy as initial palliative treatment in China, which was not associated with worsened survival. Further studies with larger sample size across China are needed to explore the relationship between this guideline non-adherence and clinical outcomes.

Progression-free survival on endocrine therapy, before or after chemotherapy, in hormone receptor-positive HER2-negative metastatic breast cancer

PURPOSE

A major question when treating HR+/HER2- metastatic breast cancer (MBC) is whether early introduction of chemotherapy (CT) increases endocrine resistance. We aimed to describe progression-free survival (PFS) under first endocrine therapy (ET) depending on whether given before or after CT in a large nationwide cohort, in the pre-CDK era.

METHODS

The real-life retrospective ESME database includes all patients with MBC whose first-line treatment was initiated between 2008 and 2014 in one of the 18 French Comprehensive Cancer Centres. Our primary objective was to compare PFS from start of first ET in patients with HR+/HER2- MBC who received ET or CT first.

RESULTS

We identified 6293 patients who received at least one ET line during their first two therapeutic lines for MBC. As first-line therapy, 3832 (60.9%) received ET alone (ET1 1st group), whilst 2461 (39.1%) received CT, including 2024 patients (32.2%) with maintenance ET after CT (ET1 after CT group). Median PFS under first ET was 12.4 months (95% CI 11.9-13.1) in ET 1st group vs. 12.6 months in ET1 after CT group (95% CI 12.1-13.4), HR 0.96 (95% CI 0.90-1.01, P = 0.1277).

CONCLUSIONS

PFS under first ET appears identical whether prescribed before or after chemotherapy. These data suggest chemotherapy does not promote endocrine resistance.

De novo Metastatic Breast Cancer Arising in Young Women: Review of the Current Evidence

Women with metastatic breast cancer remains a heterogeneous group of patients with different prognostic outcomes and therapeutic needs. Young women with de novo metastatic breast cancer (dnMBC) represent a peculiar population with respect to tumor biology, prognosis, clinical management and survivorship issues. Overall, these patients are able to attain long-term survival with a proper management of both primary tumor and distant metastases. On the other hand, they are also at higher risk of experiencing a deterioration in their quality of life (QoL) due to primary cancer-related side effects. Young women are also likely to harbor germline pathogenic variants in cancer predisposition genes which could affect treatment decisions and have a direct impact on the lives of patients' relatives. The loco-regional management of the primary tumor represents another thorny subject, as the surgical approach has shown controversial effects on the survival and the QoL of these patients. This review aims to provide an update on these issues to better inform the clinical management of dnMBC in young women.

Patient-Reported Outcomes of Palbociclib Plus Exemestane with GnRH Agonist versus Capecitabine in Premenopausal Women with Hormone Receptor-Positive Metastatic Breast Cancer: A Prospective, Open-Label, Randomized Phase ll Trial (KCSG-BR 15-10)

Simple Summary

We reported that palbociclib plus exemestane with ovarian function suppression (with leuprolide) led to significantly longer median progression-free survival compared with capecitabine in premenopausal metastatic breast cancer patients. We also evaluated differences of patient report outcomes (PROs) between palbociclib plus endocrine therapy (ET) and capecitabine as upfront therapy in this study population. All the European Organization for Research and Treatment of Cancer quality of life questionnaire (EORTC QLQ-C30) were maintained from baseline to the end of treatment within each treatment arm. Patients with palbociclib plus ET arm experienced delay in time to deterioration of physical functioning, nausea and vomiting, and diarrhea. There was a trend for worsening of insomnia in the palbociclib plus endocrine therapy (ET) arm and appetite loss in the capecitabine arm. Patients with palbociclib plus ET had significant overall improvement of quality of life and significant delay in time to deterioration without compromising treatment efficacy.

Abstract

In the era of CDK4/6 inhibitors in hormone receptor (HR)-positive, HER2-negative metastatic breast cancer, few trials have been specifically studied to compare quality of life between palbociclib plus endocrine therapy (ET) and cytotoxic chemotherapy exclusively in premenopausal women. We aimed to evaluate differences of patient report outcomes (PROs) between palbociclib plus ET and capecitabine. PROs were assessed using EORTC QLQ-C30 at baseline, every 6 weeks, and the end of treatment. All EORTC QLQ-30 scores were maintained from baseline to the end of treatment. Patients treated palbociclib plus ET arm experienced delay in time-to-deterioration of physical functioning (HR = 0.58, 95% CI, 0.36 to 0.84, p = 0.0058), nausea and vomiting (HR = 0.48; 95% CI, 0.32 to 0.73, p = 0.0005), and diarrhea (HR = 0.42; 95% CI, 0.27 to 0.65, p = 0.001). There was a numeric trend for worsening of insomnia (HR = 1.43; 95% CI, 0.96 to 2.16, p = 0.079) and favoring of appetite loss (HR = 0.69, 95% CI, 0.44 to 1.07, p = 0.09) in the palbociclib plus ET arm. Premenopausal patients with palbociclib plus ET maintained QoL without compromising treatment efficacy.

Real-World Clinical Data of Palbociclib in Asian Metastatic Breast Cancer Patients: Experiences from Eight Institutions

Purpose

Use of cyclin-dependent kinase 4/6 inhibitors improved survival outcome of hormone receptor (HR) positive metastatic breast cancer (MBC) patients, including Asian population. However, Asian real-world data of palbociclib is limited. We analyzed the real-world clinical practice patterns and outcome in HR-positive, MBC Asian patients treated with palbociclib.

Materials and Methods

Between April 2017 to November 2019, 169 HR-positive, human epidermal growth factor-2–negative MBC patients treated with letrozole or fulvestrant plus palbocilib were enrolled from eight institutions. Survival outcome (progression-free survival [PFS]), treatment response and toxicity profiles were analyzed.

Results

Median age of letrozole plus palbociclib (145 patients, 85.8%) and fulvestrant plus palbociclib (24 patients, 14.2%) was 58 and 53.5 years, with median follow-up duration of 14.63 months (range 0.2 to 33.9 months). Median PFS (mPFS) of letrozole plus palbociclib and fulvestrant plus palbociclib was 25.6 (95% confidence interval [CI], 19.1 to not reached) and 6.37 months (95% CI, 5.33 to not reached), comparable to previous phase 3 trials. In letrozole plus palbociclib arm, luminal A (hazard ratio, 2.86; 95% CI, 1.20 to 6.80; p=0.017) and patients with good performance (Eastern Cooperative Oncology Group 0–1 [hazard ratio, 3.68; 95% CI, 1.70 to 7.96]) showed better mPFS. In fulvestrant plus palbociclib group, chemotherapy naïve patients showed better mPFS (hazard ratio, 12.51, 95% CI, 1.59 to 99.17; p=0.017). The most common grade 3 or 4 adverse event was neutropenia (letrozole 86.3%, fulvestrant 88.3%).

Conclusion

To our knowledge, this is the first real-world data of palbociclib reported in Asia. Palbociclib showed comparable benefit to previous phase 3 trials in Asian patients during daily clinical practice.

Palbociclib plus exemestane with gonadotropin-releasing hormone agonist versus capecitabine in premenopausal women with hormone receptor-positive, HER2-negative metastatic breast cancer (KCSG-BR15-10): a multicentre, open-label, randomised, phase 2 trial

BACKGROUND

Endocrine treatment is recommended by clinical guidelines as the preferred treatment option for premenopausal as well as postmenopausal women with hormone receptor-positive, HER2-negative metastatic breast cancer. In real-world clinical practice, however, a substantial number of patients are treated with chemotherapy. We aimed to compare the clinical antitumour activity and safety of palbociclib plus endocrine therapy with that of capecitabine chemotherapy in premenopausal women with hormone receptor-positive, HER2-negative metastatic breast cancer.

METHODS

This multicentre, open-label, randomised, phase 2 study was done in 14 academic institutions in South Korea. Premenopausal women aged 19 years or older with hormone receptor-positive, HER2-negative breast cancer that had relapsed or progressed during previous tamoxifen therapy and with an Eastern Cooperative Oncology Group performance status of 0-2 were included. One line of previous chemotherapy for metastatic breast cancer was allowed. Patients were randomly assigned, using a random permuted block design (with a block size of two), to receive palbociclib plus combination endocrine therapy (oral exemestane 25 mg per day for 28 days and oral palbociclib 125 mg per day for 21 days every 4 weeks plus leuprolide 3·75 mg subcutaneously every 4 weeks) or chemotherapy (oral capecitabine 1250 mg/m² twice daily for 2 weeks every 3 weeks). Randomisation was stratified by previous chemotherapy for metastatic breast cancer and visceral metastasis. The primary endpoint was progression-free survival. All analyses were done in a modified intention-to-treat population that excluded patients who did not receive study medication. This study is registered with ClinicalTrials.gov, NCT02592746, and is ongoing for follow-up of overall survival.

FINDINGS

Between June 15, 2016, and Dec 10, 2018, 189 patients were enrolled, of whom 184 were randomly assigned to the palbociclib plus endocrine therapy group (n=92) or the capecitabine group (n=92). Six patients in the capecitabine group withdrew from the study before drug administration; therefore, 92 patients in the palbociclib plus endocrine therapy group and 86 patients in the capecitabine group were included in the modified intention-to-treat analyses. 46 (50%) of 92 patients in the palbociclib plus endocrine therapy group and 45 (51%) of 92 in the capecitabine group were treatment naive for metastatic breast cancer. During a median follow-up of 17 months (IQR 9-22), median progression-free survival was 20·1 months (95% CI 14·2-21·8) in the palbociclib plus endocrine therapy group versus 14·4 months (12·1-17·0) in the capecitabine group (hazard ratio 0·659 [95% CI 0·437-0·994], one-sided log-rank p=0·0235). Treatment-related grade 3 or worse neutropenia was more common in the palbociclib plus endocrine therapy group than in the capecitabine group (69 [75%] of 92 vs 14 [16%] of 86 patients). 2 (2%) patients in the palbociclib plus endocrine therapy group and 15 (17%) patients in the capecitabine group had treatment-related serious adverse events. No treatment-related deaths occurred.

INTERPRETATION

Exemestane plus palbociclib with ovarian function suppression showed clinical benefit compared with capecitabine in terms of improved progression-free survival in premenopausal patients with hormone receptor-positive, HER2-negative metastatic breast cancer. Palbociclib plus exemestane with ovarian suppression is an active treatment option in premenopausal patients with hormone receptor-positive, HER2-negative metastatic breast cancer who have been pretreated with tamoxifen.

FUNDING

Pfizer, Shinpoong, and Daewoong Korea and Takeda.

Exploratory biomarker analysis from a phase II clinical trial of eribulin plus gemcitabine versus paclitaxel plus gemcitabine for HER2-negative metastatic breast cancer patients (KCSG BR13-11)

PURPOSE

We conducted an exploratory biomarker study from a phase II clinical trial of eribulin plus gemcitabine (EG) versus paclitaxel plus gemcitabine (PG) in HER2-negative metastatic breast cancer (BC) patients.

METHODS

We performed targeted deep sequencing with a customized cancer gene panel and RNA expression assay. Tumor mutation burden (TMB) and mutation signatures were determined based on genetic alteration in targeted regions. Gene set variation analysis was performed with PanCancer Immune Profiling and PanCancer Pathway Panels. Statistical analyses were conducted to identify the associations between genetic alterations and clinical outcomes.

RESULTS

Of 119 patients, 40 had available biomarker data. Among the 40 patients, 4 supported their post-treatment tissues. In targeted deep sequencing, FAT3 (48%) was the most frequently mutated gene, followed by PKHD1, TP53, GATA3, PARP4, and PIK3CA. In terms of gene expression, low expression of epithelial-mesenchymal transition (EMT) pathway genes was associated with prolonged progression-free survival (PFS) in the EG group, while high expression of the EMT pathway was associated with good prognosis in the PG group. Median TMB was 6.5 (range 2.44-46.34) and there was no relationship between TMB and patient prognosis. Analysis of mutation signatures showed that signatures 3, 20, and 26 were frequently observed in our cohort. Further survival analysis according to mutation signature showed that mutation signature 3, as a homologous recombinant deficiency-related signature, was highly associated with disease progression (hazard ratio (log2 scale) 8.21, 95% confidence interval 2.93-13.48, p = 0.002). Kaplan-Meier plot also showed that BCs with signature 3 had short PFS compared to those without these signatures (median PFS (months) for signature 3 (low vs. high): 17.2 vs. 8.1, p = 0.0026).

CONCLUSIONS

Mutation signature 3, found in about 30% of MBCs regardless of hormone receptor status, was associated with short PFS for patients with cytotoxic chemotherapy.

TRIAL REGISTRY

ClinicalTrials.gov number: NCT02263495.