Long-term survival in patients with metastatic breast cancer receiving intensified chemotherapy and stem cell rescue: data from the Italian registry

Matching-adjusted indirect treatment comparison of ribociclib and palbociclib in HR+, HER2- advanced breast cancer

Background

Ribociclib (RIBO) and palbociclib (PALBO), combined with letrozole (LET), have been evaluated as treatments for hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer in separate Phase III randomized controlled trials (RCTs), but not head-to-head. Population differences can lead to biased results by classical indirect treatment comparison (ITC). Matching-adjusted indirect comparison (MAIC) aims to correct these differences. We compared RIBO and PALBO in hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer using MAIC.

Methods

Patient-level data were available for RIBO (MONALEESA-2), while only published summary data were available for PALBO (PALOMA-2). Weights were assigned to MONALEESA-2 patient data such that mean baseline characteristics matched those reported for PALOMA-2; the resulting matched cohort was used in comparisons. Limited by the results reported in PALOMA-2, progression-free survival (PFS) was the primary comparison. Cox regression models were used to calculate adjusted hazard ratios (HRs) for PFS, before indirect treatment comparison (ITC) was performed with 95% confidence intervals. An exploratory analysis was performed similarly for overall survival using earlier PALBO data (PALOMA-1). Grade 3/4 adverse events were also compared.

Results

Racial characteristics, prior chemotherapy setting, and the extent of metastasis were the most imbalanced baseline characteristics. The unadjusted PFS HRs were 0.556 (0.429, 0.721) for RIBO+LET versus LET alone and 0.580 (0.460, 0.720) for PALBO+LET versus LET alone. MAIC adjustment resulted in an HR of 0.524 (0.406, 0.676) for RIBO+LET versus LET. PFS ITC using unadjusted trial data produced an HR of 0.959 (0.681, 1.350) for RIBO versus PALBO, or 0.904 (0.644, 1.268) with MAIC. Unadjusted overall survival HR of RIBO versus PALBO was 0.918 (0.492, 1.710); while exploratory MAIC was 0.839 (0.440, 1.598). ITC of grade 3/4 adverse events yielded a risk ratio of 0.806 (0.604, 1.076).

Conclusion

MAIC was performed for RIBO and PALBO in the absence of a head-to-head trial: though not statistically significant, the results favored RIBO.

Downregulation of aquaporin 3 inhibits cellular proliferation, migration and invasion in the MDA-MB-231 breast cancer cell line

Aquaporins are membrane proteins that regulate cellular water flow. Recently, aquaporins have been proposed as mediators of cancer cell biology. A subset of aquaporins, referred to as aquaglyceroporins are known to facilitate the transport of glycerol. The present study describes the effect of gene knockdown of the aquaglyceroporin AQP3 on MDA-MB-231 breast cancer cell proliferation, migration, invasion, adherence and response to the chemotherapeutic agent 5-fluorouracil. shRNA mediated AQP3 gene knockdown induced a 28% reduction in cellular proliferation (P<0.01), a 39% decrease in migration (P<0.0001), a 24% reduction in invasion (P<0.05) and a 25% increase in cell death at 100 µM 5-FU (P<0.01). Analysis of cell permeability to water and glycerol revealed that MDA-MB-231 cells with knocked down AQP3 demonstrated a modest decrease in water permeability (17%; P<0.05) but a more marked decrease in glycerol permeability (77%; P<0.001). These results suggest that AQP3 has a role in multiple aspects of breast cancer cell pathophysiology and therefore represents a novel target for therapeutic intervention.

Is progression-free survival a more relevant endpoint than overall survival in first-line HR+/HER2- metastatic breast cancer?

BACKGROUND

Hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-), metastatic breast cancer (MBC) accounts for 73% of all MBCs. Endocrine therapy (ET) is the basis of first-line (1L) therapy for patients with HR+/HER2- MBC. Novel therapies have demonstrated improvements in progression-free survival (PFS) compared to ET. The clinical relevance of PFS is being debated, as there is no proven direct correlation with overall survival (OS) benefit to date. We reviewed studies of HR+/HER2- MBC to assess PFS and other factors that influence OS and treatment response, and health-related quality of life (HRQoL).

METHODS

The Embase®, Medline®, and Cochrane databases were systematically searched to identify studies in adult women with HR+/HER2- MBC, published between January 2006 and January 2017, and written in English. Phase II and III randomized controlled trials (RCTs), observational, and retrospective studies were included.

RESULTS

Seventy-nine RCTs were identified: 58 (73%) in the 1L+ setting and 21 (27%) in second-line or greater settings. PFS hazard ratios (HRs) were reported in 61 (77%) studies; 31 (39%) reported significant PFS improvements. OS was reported in 44 (41%) studies; 12 (15%) reported significant OS improvements. Significant improvements in both PFS and OS were reported in only 6 (8%) studies (1 Phase II; 5 Phase III). Patients with HER2- MBC received, on average, ≥5 lines of therapy, with no consistent treatment pathway. Baseline characteristics, prior therapies, and the type and number of post-progression therapies significantly impacted OS. PFS, response rates, and HRQoL decreased with each line of therapy (EuroQol 5 Dimensions: 0.78 1L vs. 0.70 post-progression).

CONCLUSION

Few RCTs in HR+/HER2- MBC have demonstrated significant improvements in OS. Factors other than choice of 1L therapy impact OS, including post-progression therapies, which cannot be controlled in RCTs. This study emphasizes the importance of PFS improvement in 1L treatment of HR+/HER2- MBC.

[Impact of Her2 and BRCA1/2 status in high-dose chemotherapy and autologous stem cells transplantation in the treatment of breast cancer: The Institut Paoli Calmettes' experience]

INTRODUCTION

Studies evaluating chemotherapy high dose chemotherapy with autologous haematopoietic stem cell transplantation (HDC-ACSH) in the treatment of metastatic (MBC), locally advanced (LABC) and inflammatory (IBC) breast cancer have in common lack of biomarker information, in particular the HER2 status.

PATIENTS AND METHODS

All consecutive female patients treated for breast cancer with HDC and AHSCT at Institut Paoli Calmettes between 2003 and 2012 were included. Patients were categorized in three subtypes based on hormonal receptor (HR) and HER2 status of the primary tumor: luminal, (HR+/HER2-), HER2 (HER2+, any HR) and triple negative (TN) (HER2- and HR-). The main objective was the analysis of overall survival (OS) according to the IHC subtypes.

RESULTS

Three hundred and seventy-seven patients were included. For MBC, the TN subtype appeared to have the worst prognosis with a median OS of 19.68 months (95 % CI 11.76-44.4) compared to 44.64 months (95 % CI 40.32-67.56) for the luminal subtype and a median OS not reached for the HER2 subtype (P<0.01). For IBC, HER2 subgroup appeared to have the best prognosis with a 5-year OS of 89 % (95 % CI 64-97) compared to 57 % (95 % CI 33-76) for the TN subgroup (HR 5.38, 95 % CI 1.14-25.44; P=0.034). For CSLA, luminal subgroup appeared to have the best prognosis with a 5-year OS of 92 % (95 % CI 71-98) against 75 % (95 % CI 46-90) for HER 2 subtype and 70 % (95 %CI 97-88) for TN subtype (P=0.301).

CONCLUSION

The HDC-ACSH does not change the prognosis value of IHC subtype in breast cancer patients.

Astragaloside IV inhibits breast cancer cell invasion by suppressing Vav3 mediated Rac1/MAPK signaling

BACKGROUND

Astragaloside IV (AS-IV), the major active triterpenoid in Radix Astragali, has shown anti-tumorigenic properties in certain cancers; however, its role in breast cancer remains unclear. The present study investigated the effects of AS-IV on breast cancer in vitro and in vivo and examined the underlying mechanisms.

METHODS

The effects of AS-IV on MDA-MB-231 cell proliferation, migration, invasion and metastasis were investigated by MTT and Transwell assays, and western blotting. In addition, an orthotopic mouse tumor model was established for in vivo experiments.

RESULTS

AS-IV inhibited the viability and invasive potential of MDA-MB-231 breast cancer cells, suppressed the activation of the mitogen activated protein kinase (MAPK) family members ERK1/2 and JNK, and downregulated matrix metalloproteases (MMP)-2 and -9. The effects of AS-IV were mediated by the downregulation of Vav3, a guanine nucleotide exchange factor, leading to decreased levels of activated Rac1, a Rho family GTPase. Vav3 overexpression promoted cell proliferation and invasion in vitro, whereas Vav3 silencing had the opposite effects. AS-IV suppressed orthotopic breast tumor growth and metastasis to the lungs, whereas ectopic expression of Vav3 reversed the inhibitory effect of AS-IV on cell viability, invasiveness, MAPK signaling and MMP expression.

CONCLUSION

The present results provide a mechanistic explanation for the antitumor effects of AS-IV and suggest its potential in the treatment of metastatic breast cancer.

Health-related Quality of Life in Metastatic and Adjuvant Breast Cancer Patients

Introduction: When cancer patients have advanced disease and a primary cure is no longer possible, the focus is on maintaining the patient's quality of life. Recent therapeutic advances in breast cancer treatment mean that even patients with metastatic disease can remain stable for long periods of time. The aim of this study was to look at the health-related quality of life (HRQL) of these patients and compare it with data for the general population and to show the differences in outcomes for different survey instruments used to measure quality of life. Material and Methods: A total of 96 breast cancer patients with metastatic disesae or receiving adjuvant therapy were questioned about their quality of life. Patients were investigated using the established survey instruments EORTC QLQ-C30, EORTC QLQ-BR23, EQ-5D-5L and EQ VAS. All patients filled out questionnaires. Statistical analysis was done using MS Excel and SPSS. Results: Although the questionnaires were completed at the same time, the different questionnaires showed significant differences with regard to the level of stress experienced by the patient. When the EQ VAS questionnaire was used, the patient's current state of health was assessed as significantly better than with the EORTC QLQ-C30. Overall, all aspects of patients' quality of life were found to be in need of optimization and HRQL of patients was significantly poorer in all areas compared to the reference population. Conclusion: To improve the quality of life of patients with metastatic disease, it is necessary to continuously monitor the success of therapy. The choice of survey tools is highly relevant as assessments differ considerably depending on the choice of questionnaire.

Highly favorable outcome in BRCA-mutated metastatic breast cancer patients receiving high-dose chemotherapy and autologous hematopoietic stem cell transplantation

Breast cancer carrying BRCA mutation may be highly sensitive to DNA-damaging agents. We hypothesized a better outcome for BRCA-mutated (BRCA(mut)) metastatic breast cancer (MBC) patients receiving high-dose chemotherapy and autologous hematopoietic stem cell transplantation (HDC AHSCT) versus unaffected BRCA (BRCA wild type; (BRCA(wt))) or patients without documented BRCA mutation (BRCA untested (BRCA(ut))). All female patients treated for MBC with AHSCT at Institut Paoli-Calmettes between 2003 and 2012 were included. BRCA(mut) and BRCA(wt) patients were identified from our institutional genetic database. Overall survival (OS) was the primary end point. A total of 235 patients were included. In all, 15 patients were BRCA(mut), 62 BRCA(wt) and 149 BRCA(ut). In multivariate analyses, the BRCA(mut) status was an independent prognostic factor for OS (hazard ratio (HR): 3.08, 95% confidence interval (CI): 1.10-8.64, P=0.0326) and PFS (HR: 2.52, 95% CI :1.29-4.91, P=0.0069). In this large series of MBC receiving HDC AHSCT, we report a highly favorable survival outcome in the subset of patients with documented germline BRCA mutations.

High-Dose Chemotherapy and Autologous Hematopoietic Stem Cell Transplantation as Adjuvant Treatment in High-Risk Breast Cancer: Data from the European Group for Blood and Marrow Transplantation Registry

The aim of this retrospective study was to assess toxicity and efficacy of adjuvant high-dose chemotherapy (HDC) and autologous hematopoietic stem cell transplantation (AHSCT) in 583 high-risk breast cancer (BC) patients (>3 positive nodes) who were transplanted between 1995 and 2005 in Europe. All patients received surgery before transplant, and 55 patients (9.5%) received neoadjuvant treatment before surgery. Median age was 47.1 years, 57.3% of patients were premenopausal at treatment, 56.5% had endocrine-responsive tumors, 19.5% had a human epidermal growth factor receptor 2 (HER2)-negative tumor, and 72.4% had ≥10 positive lymph nodes at surgery. Seventy-nine percent received a single HDC procedure. Overall transplant-related mortality was 1.9%, at .9% between 2001 and 2005, whereas secondary tumor-related mortality was .9%. With a median follow-up of 120 months, overall survival and disease-free survival rates at 5 and 10 years in the whole population were 75% and 64% and 58% and 44%, respectively. Subgroup analysis demonstrated that rates of overall survival were significantly better in patients with endocrine-responsive tumors, <10 positive lymph nodes, and smaller tumor size. HER2 status did not affect survival probability. Adjuvant HDC with AHSCT has a low mortality rate and provides impressive long-term survival rates in patients with high-risk BC. Our results suggest that this treatment modality should be considered in selected high-risk BC patients and further investigated in clinical trials.

Long-term survival after high-dose chemotherapy with autologous hematopoietic cell transplantation in metastatic breast cancer

OBJECTIVE/BACKGROUND

The most common indication for high-dose chemotherapy (HDC) and autologous hematopoietic cell transplantation (AHCT) in the 1990s was breast cancer. Several randomized trials and a more recent meta-analysis failed to show a survival benefit for AHCT in metastatic breast cancer (MBC); however, they demonstrated a better-than-expected 10-year to 15-year survival in 5-15% of patients. We thus evaluated the long-term results of treatment with HDC and AHCT in MBC at our institution.

METHODS

From 1984 to 2000, 285 patients underwent AHCT for MBC. The patient characteristics were collected through the Cleveland Clinic, United Transplant Database. A retrospective review of the medical records of the long-term surviving breast-cancer patients treated with HDC and AHCT was conducted.

RESULTS

With a median follow-up of 169 months, 34 (12%) remain alive. Of the 251 patients who died, 218 (87%) died of metastatic disease. A comparison by age (<50 years and >50 years) and hormonal status did not demonstrate any differences in relapse (p=.33 and p=.32, respectively) or survival (p=.13 and p=.42). Of the 34 long-term survivors, sufficient data were available on 28 patients, and further evaluation revealed that the majority had a primary or locally recurrent oligometastatic disease.

CONCLUSION

This retrospective evaluation of patients who underwent AHCT for MBC demonstrates long-term survival in a small subset of patients, primarily those with primary or recurrent oligometastatic disease. Oligometastatic breast cancer is a distinct entity within MBC, which may be curable with multimodality therapy. We thus conclude there remains no overall-survival benefit to HDC in MBC.

Indications for allo- and auto-SCT for haematological diseases, solid tumours and immune disorders: current practice in Europe, 2015

This is the sixth special report that the European Society for Blood and Marrow Transplantation regularly publishes on the current practice and indications for haematopoietic SCT for haematological diseases, solid tumours and immune disorders in Europe. Major changes have occurred in the field of haematopoietic SCT over the last years. Cord blood units as well as haploidentical donors have been increasingly used as stem cell sources for allo-SCT, thus, augmenting the possibility of finding a suitable donor for a patient. Continuous refinement of conditioning strategies has also expanded not only the number of potential indications but also has permitted consideration of older patients or those with co-morbidity for a transplant. There is accumulating evidence of the role of haematopoietic SCT in non-haematological disorders such as autoimmune diseases. On the other hand, the advent of new drugs and very effective targeted therapy has challenged the role of SCT in some instances or at least, modified its position in the treatment armamentarium of a given patient. An updated report with revised tables and operating definitions is presented.