Abstract P4-13-14: Time on treatment of everolimus, fulvestrant, and capecitabine for the treatment of HR+/HER2- metastatic breast cancer: A retrospective claims study in the US

Background:

Treatment guidelines for hormone receptor-positive/human epidermal growth factor receptor-2-negative (HR+/HER2-) metastatic breast cancer (mBC) recommend extending the time on treatment (TOT) of endocrine therapy (ET) prior to the initiation of chemotherapy (CT) to avoid its serious side effects and preserve patients' quality of life. Everolimus-based therapy (EVE), fulvestrant monotherapy (FUL mono), and capecitabine monotherapy (CAP mono) are among the latest ET and CT agents approved for the treatment of HR+/HER2- mBC in the US. This retrospective claims analysis compared TOT among HR+/HER2- mBC patients who received EVE versus those who received FUL mono or CAP mono respectively.

Methods:

Postmenopausal women with HR+/HER2- mBC who initiated ≥ 1 new line of therapy for mBC between 7/20/2012 (the approval date of EVE, the latest of all three therapies) and 3/31/2014 (which allowed for ≥ 3 months of potential follow-up) after a non-steroidal aromatase inhibitor were identified from the MarketScan and PharMetrics databases (2002Q1-2014Q2) using an algorithm adapted from the literature. Treatment discontinuation was defined as a treatment gap of ≥ 60 days. Patients' lines of therapies were classified into mutually-exclusive regimen groups (i.e., EVE, FUL mono, and CAP mono) and followed until discontinuation of the line of therapy, end of insurance eligibility, or data cut-off (06/30/2014). Patients who did not discontinue their treatment were censored at the end of follow-up. TOT was compared between EVE versus FUL mono and versus CAP mono using Kaplan-Meier (K-M) analyses with log-rank tests and multivariable Cox models adjusting for the line of therapy and differences in patient characteristics, including age, insurance type, de novo vs non-de-novo mBC, prior use of CT for mBC, sites of metastases (e.g., bone, brain, and visceral), and Charlson comorbidity index.

Results:

Across the first four lines of therapies for mBC, a total of 940 EVE, 953 FUL mono, and 721 CAP mono regimens were included. Based on the different lines of therapies, the K-M estimators of median TOT ranged from 5.5 to 7.2 months for EVE, 4.9 to 8.4 months for FUL mono, and 3.5 to 6.0 months for CAP mono.

Table 1. Comparison of TOT between EVE, FUL mono, and CAP mono by line of therapy Median TOT (months) EVEFUL monoCAP monoLine 16.28.43.5*Line 26.25.64.6*Line 37.25.3*6.0*Line 45.54.95.1**indicates p-value <0.05 for pairwise log-rank tests in comparison with EVE.

Pooling all lines of therapies, EVE was associated with significantly longer TOT compared to FUL mono (multivariable-adjusted hazard ratio [HR] = 0.87, 95% confidence interval [CI]: 0.76-0.99) or CAP mono (multivariable-adjusted HR = 0.73, 95% CI: 0.64-0.83). Similar results were observed in each line of therapy.

Conclusions:

This real-world US claims study of postmenopausal women with HR+/HER2- mBC showed that patients receiving EVE experienced significantly longer TOT than those receiving FUL mono or CAP mono, suggesting a comparative advantage of EVE in extending the duration of ET.

Citation Format: Li N, Hao Y, Kageleiry A, Peeples M, Fang A, Koo V, Guérin A. Time on treatment of everolimus, fulvestrant, and capecitabine for the treatment of HR+/HER2- metastatic breast cancer: A retrospective claims study in the US. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-13-14.

Abstract P2-08-20: Clinical outcomes among HR+/HER2- metastatic breast cancer patients with multiple metastatic sites

Background:

Hormone receptor-positive, human epidermal growth factor receptor-2-negative (HR+/HER2-) is the most common type of metastatic breast cancer (mBC). While overall the prognosis among these patients is poor with short progression-free survival (PFS) and overall survival (OS), those with multiple metastatic sites (multiple mets) may have even worse clinical outcomes due to multiple organ involvement. This real-world study examined clinical outcomes among HR+/HER2- mBC patients with multiple mets.

Methods:

In this retrospective chart review, a sample of postmenopausal women with HR+/HER2- mBC was collected from community-based oncology practices in the US. Patients were required to have failed a non-steroidal aromatase inhibitor and later initiated a new treatment (defined as the index therapy) for mBC between July 1, 2012 and April 15, 2013. Patients were classified into two mutually exclusive groups: multiple mets or single metastatic site (single met), based on the number of non-lymph-node metastatic sites at index therapy initiation. PFS, time on treatment (TOT), and OS were compared between the two study groups using Kaplan-Meier analyses with log-rank tests and multivariable Cox proportional hazards models adjusting for baseline characteristics, including age, race, insurance, mBC type, and months from initiation of last adjuvant endocrine therapy to mBC diagnosis, index therapy type, index therapy line, adjusted Charlson comorbidity index (CCI), Eastern Cooperative Oncology Group (ECOG) performance status, and prior chemotherapy for mBC. Patients without an event were censored at the last follow-up. In addition, separate Cox proportional hazard models were conducted including an interaction term between line of therapy and study group to assess the impact of multiple mets on clinical outcomes across different lines of therapy.

Results:

A total of 408 patients in the single met group and 291 patients in the multiple mets group were included. Patients with multiple mets had worse ECOG performance status and a higher rate of prior chemotherapy use for mBC compared with patients in the single met group. Relative to patients with single met, patients with multiple mets were associated with significantly shorter PFS (log-rank test p<0.001, hazard ratio (HR)=1.68, 95% confidence interval (CI): 1.32-2.14), TOT (log-rank test p<0.001, HR=1.37, 95% CI: 1.09-1.72) and OS (log-rank test p<0.001, HR=1.71, 95% CI: 1.12-2.63). Similar outcomes were observed in each line of therapy.

Table 1. Multivariable -adjusted comparisons of PFS, TOT, and OS between patients with multiple mets and single met by line of therapy PFSTOTOSMultiple mets vs. single metHR (95% CI)p-valueHR (95% CI)p-valueHR (95% CI)p-valueLine of therapy 11.51 (1.04,2.19)0.030*1.22 (0.86,1.73)0.2561.94 (1.06,3.56)0.032*Line of therapy 21.79 (1.17,2.74)0.008*1.50 (1.02,2.21)0.042*2.35 (1.03,5.38)0.043*Line of therapy 3+1.82 (1.18,2.83)0.007*1.46 (0.97,2.21)0.0721.03 (0.48,2.20)0.936*P < 0.05

Conclusion:

Among HR+/HER2- mBC patients, those with multiple mets had significantly worse clinical outcomes, highlighting substantial disease burden and unmet need for more efficacious treatment for these patients.

Citation Format: Xie J, Hao Y, Li N, Lin PL, Ohashi E, Koo V, Wu EQ. Clinical outcomes among HR+/HER2- metastatic breast cancer patients with multiple metastatic sites. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-08-20.

Abstract P4-13-13: Real-world effectiveness of everolimus versus endocrine monotherapy or chemotherapy in HR+/HER2- metastatic breast cancer patients with liver metastasis or multiple metastatic sites

Background:

Liver metastasis and multiple metastatic sites are associated with higher risk of progression or death among women with hormone receptor-positive, human epidermal growth factor receptor-2-negative (HR+/HER2-) metastatic breast cancer (mBC). Traditional treatments, like endocrine monotherapy (ET mono) or chemotherapy (CT), have limited effectiveness in these high-risk patients. Everolimus-based therapy (EVE) is a new treatment option with different mechanism of action. This study examined the real-world comparative effectiveness of EVE vs. ET mono or CT in patients with liver metastasis or multiple metastatic sites.

Methods:

A sample of postmenopausal women with HR+/HER2- mBC was obtained through a retrospective chart review of community-based oncology practices in the US. All patients initiated EVE, ET mono, or CT (defined as the index therapy) for mBC between July 2012 and April 2013 after the failure of a non-steroidal aromatase inhibitor. Patients with liver metastasis and those with multiple metastatic sites (i.e., ≥2 non-lymph-node metastases) at the index therapy initiation were analyzed separately. In each group, progression-free survival (PFS) and time on treatment (TOT) were compared between EVE vs. ET mono or CT, respectively, using Kaplan-Meier analyses with log-rank tests and Cox proportional hazards models adjusting for patient and disease characteristics, such as age, mBC type, performance status, tumor burden, and prior treatment. Patients without an event were censored at the last follow-up.

Results:

A total of 202 patients had liver metastasis, including 82 treated with EVE, 49 with ET mono, and 71 with CT. EVE patients had more severe mBC than ET mono patients and less severe mBC than CT patients, as indicated by proportion of patients receiving prior CT for mBC and tumor burden. Compared with ET mono, EVE was associated with significantly longer PFS (log-rank test p=0.049; hazard ratio (HR)=0.48, 95% confidence interval (CI): 0.27-0.87) and TOT (log-rank test p=0.054, HR=0.49, 95% CI: 0.28-0.86). Similarly, compared with CT, EVE was associated with significantly longer PFS (log-rank test p=0.024, HR=0.76, 95% CI: 0.44-1.32) and TOT (log-rank test p<0.001, HR=0.35, 95% CI: 0.22-0.55).

A total of 265 patients had multiple metastatic sites, including 100 treated with EVE, 79 with ET mono, and 86 with CT. Similarly, EVE patients had more severe mBC than ET mono patients and less severe mBC than CT patients, as indicated by tumor burden. Compared with ET mono, EVE was associated with significantly longer PFS (log-rank test p=0.043, HR=0.62, 95% CI: 0.41-0.95) and TOT (log-rank test p=0.054, HR=0.64, 95% CI: 0.42-0.97). Compared with CT, EVE was also associated with longer PFS (log-rank test p=0.004, HR=0.60, 95% CI: 0.39-0.92) and TOT (log-rank test p<0.001, HR=0.36, 95% CI: 0.24-0.53).

Conclusion:

In this retrospective chart review of HR+/HER2- mBC patients, EVE was associated with significantly longer PFS and TOT compared with ET mono or CT in high-risk patients with liver metastasis or multiple metastatic sites.

Citation Format: Li N, Hao Y, Lin PL, Koo V, Ohashi E, Wu EQ, Xie J. Real-world effectiveness of everolimus versus endocrine monotherapy or chemotherapy in HR+/HER2- metastatic breast cancer patients with liver metastasis or multiple metastatic sites. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-13-13.

Zoledronic acid suppresses callus remodeling but enhances callus strength in an osteoporotic rat model of fracture healing

MINI-ABSTRACT

In this study, we demonstrated that the use of zoledronic acid does not impair fracture healing, but results in superior callus size and resistance at the fracture site, which could be the consequence of a lower rate of bone turnover due to its anti-catabolic effect.

OBJECTIVE

To investigate the effect of inhibition of bone remodeling by the bisphosphonate, zoledronic acid, on callus properties in an osteoporotic rat model of fracture healing.

METHODS

Ovariectomized (OVX) rats were randomly divided into four treatment groups (n=24 per group): saline control (CNT); and three systemic zoledronic acid-injected groups (0.1mg/kg), administered 1 day (ZOLD1), 1 week (ZOLW1), and 2 weeks (ZOLW2) after fracture. Rats were killed at either 6 or 12 weeks postoperatively. Postmortem analyses included radiography, microcomputed tomography, histology, histomorphometry, biomechanical tests, and nanoindentation tests.

RESULTS

Treatment with zoledronic acid led to a significant increase in trabecular bone volume within the callus, as well as in callus resistance, compared to those in the saline control rats; delayed administration (ZOLW2) reduced intrinsic material properties, including ultimate stress and elastic modulus, and microarchitecture parameters, including bone volume/total volume (BV/TV), trabecular thickness (Tb.Th), and connectivity density (Conn.D), compared with ZOLD1 at 12 weeks after surgery. OVX had a negative effect on the progression of endochondral ossification at 6 weeks. Zoledronic acid administration at an early stage following fracture may bind to early callus, and thus not affect subsequent callus formation and endochondral ossification, while delayed administration (ZOLW2) mildly suppresses bony callus remodeling.

CONCLUSION

The superior results obtained with zoledronic acid (ZOLD1, ZOLW1, and ZOLW2) compared to CNT in terms of callus size and resistance could be the consequence of a lower rate of bone turnover at the fracture site due to the anti-catabolic effect of zoledronic acid. Mild suppression of callus remodeling by delayed administration did not impair the initial phase of the fracture healing process.

Well plate-based perfusion culture device for tissue and tumor microenvironment replication

There are significant challenges in developing in vitro human tissue and tumor models that can be used to support new drug development and evaluate personalized therapeutics. The challenges include: (1) working with primary cells which are often difficult to maintain ex vivo, (2) mimicking native microenvironments from which primary cells are harvested, and (3) the lack of culture devices that can support these microenvironments to evaluate drug responses in a high-throughput manner. Here we report a versatile well plate-based perfusion culture device that was designed, fabricated and used to: (1) ascertain the role of perfusion in facilitating the expansion of human multiple myeloma cells and evaluate drug response of the cells, (2) preserve the physiological phenotype of primary murine osteocytes by reconstructing the 3D cellular network of osteocytes, and (3) circulate primary murine T cells through a layer of primary murine intestine epithelial cells to recapitulate the interaction of the immune cells with the epithelial cells. Through these diverse case studies, we demonstrate the device's design features to support: (1) the convenient and spatiotemporal placement of cells and biomaterials into the culture wells of the device; (2) the replication of tissues and tumor microenvironments using perfusion, stromal cells, and/or biomaterials; (3) the circulation of non-adherent cells through the culture chambers; and (4) conventional tissue and cell characterization by plate reading, histology, and flow cytometry. Future challenges are identified and discussed from the perspective of manufacturing the device and making its operation for routine and wide use.

Psychrophilic fungi from the world's roof

During a survey of cold-adapted fungi in alpine glaciers on the Qinghai-Tibet Plateau, 1 428 fungal isolates were obtained of which 150 species were preliminary identified. Phoma sclerotioides and Pseudogymnoascus pannorum were the most dominant species. Psychrotolerant species in Helotiales (Leotiomycetes, Ascomycota) were studied in more detail as they represented the most commonly encountered group during this investigation. Two phylogenetic trees were constructed based on the partial large subunit nrDNA (LSU) to infer the taxonomic placements of these strains. Our strains nested in two well-supported major clades, which represented Tetracladium and a previously unknown lineage. The unknown lineage is distant to any other currently known genera in Helotiales. Psychrophila gen. nov. was therefore established to accommodate these strains which are characterised by globose or subglobose conidia formed from phialides on short or reduced conidiophores. Our analysis also showed that an LSU-based phylogeny is insufficient in differentiating strains at species level. Additional analyses using combined sequences of ITS+TEF1+TUB regions were employed to further investigate the phylogenetic relationships of these strains. Together with the recognisable morphological distinctions, six new species (i.e. P. antarctica, P. lutea, P. olivacea, T. ellipsoideum, T. globosum and T. psychrophilum) were described. Our preliminary investigation indicates a high diversity of cold-adapted species in nature, and many of them may represent unknown species.

Intrinsic and extrinsic risk factors for nonunion after nonoperative treatment of midshaft clavicle fractures

BACKGROUND

The optimal treatment of midshaft clavicle fractures remains controversial. Nonunion is usually considered to be an uncommon complication following a nonoperatively treated clavicle fracture.

HYPOTHESIS

Not every midshaft clavicular fractures shares the same risk of developing nonunion after nonoperative treatment. The present study was performed to identify the intrinsic and extrinsic independent factors that are independently predictive of nonunion in patients with midshaft clavicular fractures after nonoperative treatment.

MATERIALS AND METHODS

We performed a retrospective study of a series of 804 patients (391 men and 413 women with a median age of 51.3 years) with a radiographically confirmed midshaft clavicle fracture, which was treated nonoperatively. There were 96 patients who underwent nonunion. Putative intrinsic (patient-related) and extrinsic (injured-related) risk factors associated with nonunion were determined with the use of bivariate and multivariate statistical analyses.

RESULTS

By bivariate analysis, the risk of nonunion was significantly increased by several intrinsic risk factors including age, sex, and smoking and extrinsic risk factors including displacement of the fracture and the presence of comminution (P<0.05 for all). On multivariate analysis, smoking (OR=4.16, 95% CI: 1.01-14.16), fracture displacement (OR=7.81, 95% CI: 2.27-25.38) and comminution of fracture (OR=3.86, 95% CI: 1.16-13.46) were identified as independent predictive factors.

CONCLUSION

The risk factors for nonunion after nonoperative treatment of midshaft clavicle fractures are multifactorial. Smoking, fracture displacement and comminution of fracture are independent predictors for an individual likelihood of nonunion. Further studies are still required to evaluate these factors in the future.

LEVEL OF EVIDENCE

Level III, case-control study.

Highly ordered core–shell CoFe2O4–BiFeO3 nanocomposite arrays from dimension confined phase separation and their interfacial magnetoelectric coupling properties

With dimension confinement, highly ordered core–shell CoFe₂O₄–BiFeO₃ nanocomposite arrays were obtained from the self-assembly phase separation.

IL-1α -889 C/T polymorphism and cancer susceptibility: a meta-analysis

The -889 C/T polymorphism in the interleukin-1α (IL-1α) gene has been implicated in the risk of cancer, but the results are inconclusive. The present meta-analysis aimed to investigate the association between the -889 C/T polymorphism and cancer risk. A literature search in PubMed, Embase™, Web of Science™, Science Direct^®, SpringerLink, EBSCO, Wanfang, and Chinese National Knowledge Infrastructure (CNKI) databases was carried out to identify studies investigating the association between IL-1α -889 C/T polymorphism and cancer risk. The odds ratio (OR) with 95% confidence interval (CI) were used to assess the strength of association. A total of 20 publications, involving 6,782 cases and 7,767 controls, were included in this meta-analysis. Combined analysis revealed a significant association between -889 C/T polymorphism and cancer risk under an allele model (OR =1.12, 95% CI =1.02–1.24, P=0.02), recessive model (OR =1.34, 95% CI =1.06–1.68, P=0.01), and homozygous comparison (OR =1.38, 95% CI =1.10–1.74, P<0.01). Subgroup analysis by ethnicity showed there was significant association between cancer risk and IL-1α -889C/T polymorphism in Asian populations under a recessive model (OR =2.57, 95% CI =1.11–5.98, P=0.03) and homozygous comparison (OR =2.60, 95% CI =1.12–6.04, P=0.03). Moreover, a subgroup analysis was conducted by source of control, and a statistically increased cancer risk was found in the hospital-based group, under a recessive model (OR =1.62, 95% CI =1.03–2.56, P=0.04) and homozygous comparison (OR =1.67, 95% CI =1.04–2.68, P=0.03). This meta-analysis suggests that IL-1α -889 C/T polymorphism contributes to cancer susceptibility. Further large and well-designed studies are needed to confirm this association.

Illusions and cloaks for surface waves

Ever since the inception of Transformation Optics (TO), new and exciting ideas have been proposed in the field of electromagnetics and the theory has been modified to work in such fields as acoustics and thermodynamics. The most well-known application of this theory is to cloaking, but another equally intriguing application of TO is the idea of an illusion device. Here, we propose a general method to transform electromagnetic waves between two arbitrary surfaces. This allows a flat surface to reproduce the scattering behaviour of a curved surface and vice versa, thereby giving rise to perfect optical illusion and cloaking devices, respectively. The performance of the proposed devices is simulated using thin effective media with engineered material properties. The scattering of the curved surface is shown to be reproduced by its flat analogue (for illusions) and vice versa for cloaks.

Estrogen receptor α gene polymorphisms and risk of Alzheimer's disease: evidence from a meta-analysis

Objective

Human estrogen receptor α (ESR1), a member of the nuclear receptor superfamily of ligand-activated transcription factors, is one of the key mediators of hormonal response in estrogen-sensitive tissues. Accumulating evidence has demonstrated that two of the most widely studied single-nucleotide polymorphisms in ESR1 – PvuII (T/C, rs223493) and Xbal (A/G, rs9340799) – are possibly associated with Alzheimer’s disease (AD). However, individual study results are still controversial.

Materials and methods

We searched PubMed, Embase, Web of Science, Science Direct, SpringerLink, and the Chinese National Knowledge Infrastructure databases for eligible studies assessing the association of ESR1 polymorphisms and AD risk (last search performed in November 2013). Thereafter, a meta-analysis of 13,192 subjects from 18 individual studies was conducted to evaluate the association between ESR1 polymorphisms and susceptibility to AD.

Results

The results indicated that a significant association was found between the ESR1 PvuII polymorphism and AD risk in Caucasian populations (CC + CT versus TT, odds ratio [OR] 1.14, 95% confidence interval [CI] 1.02–1.28, P=0.03; CT versus TT, OR 1.16, 95% CI 1.02–1.31, P=0.02), whereas no evidence of association was found in Asian populations. Nevertheless, we did not find any significant association between the ESR1 XbaI polymorphism and AD risk for any model in Caucasian and Asian populations (all P>0.05).

Conclusion

Based on this meta-analysis, we conclude that the ESR1 PvuII polymorphism might be a risk factor in AD development in Caucasian populations, not in Asian populations. Further confirmation is needed from better-designed and larger studies.

Lenses on curved surfaces

This Letter presents a theory that allows graded index lenses to be mapped onto arbitrary rotationally symmetric curved surfaces. Examples of the Luneburg and Maxwell fish-eye lens are given, for numerous surfaces, always resulting in isotropic permittivity requirements. The performance of these lenses is initially illustrated with full-wave simulations utilizing a waveguide structure. A transformation of the refractive index profiles is then performed to design surface-wave lenses, where the dielectric layer is not only isotropic but also homogenous, demonstrating the applicability and ease of fabrication.